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2D optomechanics (Thema ist bereits vergeben) |
Poot |
- Arbeitsgruppe
- Quantentechnologien
- Beschreibung
Optomechanics is an extremely exciting field where the tiniest motions of mechanical resonators are measured with the help of laser light. So far, most of these experiments have been done with beams and cantilevers, in other words with one-dimensional structures. In the Quantum Technologies Lab we have just build a new setup, where we can measure the vibrations of 2D mechanical systems.
The goal of this project is to explore the world of 2D optomechanics. For this, we have two kinds of samples in mind: one is made from silicon nitride, which is a material with extremely high quality factors. This material is not only used in the manufacturing process of chips, but is also a great material to do optomechanics with. The other direction is to use materials that are just a few atoms thick: This includes graphene, boron nitride, and sandwiches of these true 2D materials. For this, we collaborate with the Karlsruhe Institute of Technology.
We will make the samples for you in the cleanroom, and it will be your goal to measure them with our new setup. This includes their optical characterization, as well as electrical measurements in the time domain (oscilloscope) and in the frequency domain (network- and spectrum analyzer). For the measurement and data processing, we already have a range of computer programs available in our group, so that you can start measuring right away. Depending on your preferences, the project could be completely experimental, or also contain a modelling component.
The project is envisioned with students in Applied and Engineering Physics (AEP) and Condensed Matter Physics (KM) in mind, but if you follow another track we are still interested to hear from you. Being curious and wanting to get a feeling for what doing real research is about, is the most important factor. There are no formal requirements on courses taken.
- Forschungsfeld
- Nanostrukturen (experimentell) (~50%)
- Optik (experimentell) (~50%)
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Aufbau einer Gasdruckzelle zur Messung der Positronenzerstrahlung in reinen Gasen (Thema ist bereits vergeben) |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
- Die koinzidente Doppler-Verbreiterungsspektroskopie (CDBS) ist eine hochsensitive Positronentechnik, um die chemische Umgebung von Leerstellen in Festkörpern experimentell zu bestimmen. Für CDBS sind Referenzzmessungen an verschiedenen Elementen, die üblicherweise an hochreinen Feststoffen erfolgen, von herausragender Bedeutung. Um die erstmalige Messung solcher Referenzspektren für Gase wie Sauerstoff und Stickstoff zu ermöglichen, soll im Rahmen dieser Arbeit eine Gasdruckzelle aufgebaut werden.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- interdisziplinäre Themen (experimentell) (~30%)
- Kernphysik (experimentell) (~20%)
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Aufbau eines Michelson-Interferometers zur Detektion des magneto-optischen Kerr Effekts (Thema ist bereits vergeben) |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
- In dieser Arbeit soll ein neues Konzept für die Messung des magneto-optischen Kerr Effekts erprobt werden. Hierzu soll ein Michelson-Interferometers aufgebaut werden und die Auslesesoftware programmiert werden. Ziel ist es die Stabilität dieses neuen magneto-optischen Aufbaus an ultra dünnen magnetischen Schichten zu testen.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Christian Riedel
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Aufbau eines Systems zur Spektroskopie von Szintillatoren mit einem Laser (Thema ist bereits vergeben) |
Oberauer |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- In unserer Gruppe werden optische Eigenschaften von Szintillatoren vermessen, die in zukünftigen Experimenten als Target und Nachweismedium für niederenergetische Neutrinos dienen sollen. In diesem Rahmen wollen wir die rein elektromagnetische Anregung von Szintillatoren und ihren Komponenten mithilfe eines Lasers bestimmen und mit der von Teilchen vergleichen. Aus diesem Vergleich erhoffen wir neue Einsichten zur modellhaften Beschreibung von Energietransfermechanismen im Szintillator zu gewinnen. Die Arbeit umfasst den Aufbau des Lasers mit der Szintillatorprobe, eines Photomultipliers, die Eichung des Systems und wenn möglich erste Messungen. Die Arbeit wird in unserem Labor in Garching durchgeführt werden und wird mitbetreut von Herrn Raphael Stock.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Matthias Raphael Stock
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Aufbau eines Triggersdetektors |
Fabbietti |
- Arbeitsgruppe
- Dichte und seltsame hadronische Materie
- Beschreibung
- Höchst sensitive, großflächige Teilchendetektoren sind immer noch ein heißes Thema in der modernen Teilchenphysik. Unsere Arbeitsgruppe hat in den letzten Jahren wesentliche Entwicklungen im Bereich der Gas Electron Multiplier (GEM) für das ALICE Experiment am LHC durchgeführt und die Leitung beim Aufbau des riesigen GEM Detektors für die ALICE TPC, der in diesem Jahr in Betrieb gehen wird. Wir wollen diese Arbeiten aber noch erweitern und GEM Detektoren auch zum Nachweis einzelner Photonen einsetzen. Dazu gilt es die Verstärkerfolien mit einer photosensitiven Schicht auszustatten und dann mit einem Cherenkov-Radiator und kosmischen Myonen als definierte Lichtquelle zu charakterisieren. Ihre Aufgabe ist es in Zusammenarbeit mit unseren Doktoranden einen Testaufbau mit zwei Faserdetektoren zu erstellen, mit dem es gelingt Richtung und Form des Cherenkovkegels zu definieren und damit die GEM Folien zu beleuchten. Sie lernen dabei nicht nur modernste experimentelle Techniken wie Silizium Photomultiplier und GEM Detektoren kennen, sondern gehen auch erste Schritte beim Umgang mit hochintegrierter Datenaufnahme Elektronik auf Basis von Field Programmable Gate Arrays (FPGAs), die eine wesentliche Basis von künstlicher Intelligenz sind.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Thomas Klemenz
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Aufbau und Charakterisierung eines Michelson-Interferometers zur Stabilitätsmessung eines optischen Aufbaus (Thema ist bereits vergeben) |
Kienberger |
- Arbeitsgruppe
- Laser- und Röntgenphysik
- Beschreibung
- Gegenstand dieser Arbeit ist sowohl der Aufbau eines Michelson-Interferometers als auch das Programmieren einer Auslesesoftware des Signals der überlagerten, interferierenden Laserstrahlen. Das Ziel ist eine Charakterisierung dieses neuen optischen Aufbaus und dessen Stabilität.
- Forschungsfeld
- Quantenoptik (experimentell)
- Betreuer(innen)
- Maximilian Pollanka
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Block copolymer membranes for lithium ion microbatteries |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Lithium ion microbattery is the type of battery where all components (electrodes, membrane, and packaging) are in the thin film format. The need for such types of batteries is to provide lightweight and shape flexible solid-state energy sources for some miniature medical devices, such as implantable pumps, biosensors, and wireless capsule endoscopes. Membrane based on mixing both lithium slat and polyelectrolyte block copolymers will be prepared and investigated using small-angle X-ray scattering and impedance spectroscopy. The effect of a third component such as inorganic SiO2 nanoparticles on the morphology and conductivity of the prepared thin film membranes will be studied. The best performing membrane will be assembled between two electrodes to probe the performance of a complete assembly of a solid-state lithium battery. The project will involve a literature review, sample preparation, x-ray scattering and impedance spectroscopy.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Characterization of phase stability of synchronized vector signal generators (Thema ist bereits vergeben) |
Filipp |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
Realization of quantum computers consisting of a few tens of qubits has become a possibility in recent years. In order to do computations, quantum gates must be applied onto qubits. In the Q-Computing lab, qubits are realized using superconducting circuits and quantum gates are applied using microwave pulses. To generate microwave pulses we use In-phase and Quadrature (IQ) modulation where we use an IQ mixer to mix a continuous microwave tone generated by a microwave signal generator called Local Oscillator (LO) and external IQ signals generated by Arbitrary Waveform Generators(AWGs). In this setup correct timing (set by IQ signals) and phase synchronization(set by microwave tone) of multiple pulses applied to the same qubit and pulses applied to different qubits is necessary. Lack of synchronization of pulses and phase instability of signal generator leads to errors in quantum gates and degrades the performance of a quantum computer. In this project you will characterize the phase stability of synchronized (microwave) vector signal generators with built in IQ mixing. You will learn about signal generation & noise in signal generators, IQ modulation, signal detection and analysis, thereby gaining a practical perspective on the challenges in operating a quantum computer.
- Forschungsfeld
- Quantenoptik (experimentell) (~50%)
- Festkörperphysik (experimentell) (~50%)
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Classical Lumps and their quantum descendants |
Weiler |
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Conductive paper |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Transparent flexible substrates with electrical conductivity are an essential component for display technologies of devices like smartphones. In organic photovoltaics the use of flexible substrates allows for applications with a new versatility. We follow an environmentally friendly approach with the use of nanocellulose derived from wood in combination with conductive polymers. This project comprises the preparation of composite films with printing technology and the characterization of conductivity and optical properties.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Deep neural networks applied to multimessenger astronomy: real-time neutrino astronomy. |
Resconi |
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Dekohärenz und Tunneln (Thema ist bereits vergeben) |
Garbrecht |
- Arbeitsgruppe
- Theoretische Physik des frühen Universums
- Beschreibung
- Tunneling in quantum mechanics can be described by a quantum mechanical probability current penetrating through a barrier. An observer perceives this as a decay rate, i.e. as a likelihood of a particle to appear in a certain time interval. Decoherence theory is to be applied here in order to describe this without invoking the collapse of a wave function. The resolution of this question may help to resolve apparent paradoxes in phase transitions through bubble nucleation.
- Forschungsfeld
- Teilchen und Felder (Theorie)
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Detektierung von schwachen Transient Quellen |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- The recent detection of gravitational waves (GW) with the advanced LIGO/Virgo instruments in conjunction with a short gamma-ray burst (GRB) has surprised gamma-ray astronomers because of the substantially different properties of the GRB signal as compared to canonical GRBs. This motivates an "open-mind" search for untriggered transient events in the data stream of the gamma-ray burst monitor (GBM) on the Fermi satellite. With a previous Master thesis we have developed an automated search for gamma-ray transients in Fermi/GBM data.
This thesis shall be devoted to test this new procedure, and establish a Python program for studying these newly identified transients in existing data of other missions, primarily the Swift/BAT survey, with the goal of a good localization.
The project includes elements from computational and observational high-energy astrophysics, and will allow for obtaining extensive knowledge on the broad class of high-energy transients.
Some background in astrophysics is advantageous, but affinity with
Python programming is a must.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
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Development of an advanced detector for metastable Hydrogen atoms (H(2s)) from the bound neutron decay (BOB) (Thema ist bereits vergeben) |
Paul |
- Arbeitsgruppe
- Hadronenstruktur und Fundamentale Symmetrien
- Beschreibung
- In order to improve the non-Standard Model weak interaction scalar and tensor coupling upper limits by an order of magnitude and to determine the helicity of an antineutrino combined with a low velocity charged lepton, the free neutron bound beta decay ( ) (BOB) is to be measured. Thereby, mono energetic metastable BOB H(2s) atoms (T=326 eV) with a single hyperfine state, selected by a spin filter, generated at the center of a an high flux beam reactor through going beam tube (FRMII,ILL Grenoble or PIK reactor, Gatchina), are transformed with high efficiency (~ 15%) into ions within an Ar cell. After extraction from the beam tube by means of a pulsed electric deflector, the are measured by a velocity filter based on the Bradbury Nielsen Gate technology and an MCP detector. Although the bound beta decay branching ratio is small ( ), the experiment seams feasible (several counts/s rate). Another way to detect the H(2s) atoms could be the application of metal (carbon foil) or semiconductor layers, where the transition energy 2s -> 1s is used to extract free electrons from these layers . This method was also applied by Lamb, to measure the Lamb-shift and measure them with a multi-channel-plate (MCP). The big advantage of this method is very likely the high detection efficiency for meta-stable H(2s) atoms. This would improve the statistics in the future BOB-experiment on a reactor like the PIK in Gatchina significantly.
Your task:
Design and construction of a detector for metastable H(2s)atoms.
Measurements with this detector on an existing proton source, where H(2s) atoms are generated by protons which move through a Cesium vapor, where they catch an electron and become a hydrogen atom.
Contact:
Dr. Erwin Gutsmiedl
Email: Erwin.Gutsmiedl@mytum.de
Tel.: 089-28914464
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Erwin Gutsmiedl
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Development of a Yb:KYW microchip laser (Thema ist bereits vergeben) |
Kienberger |
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Die Physik von GRB Spektren (Thema ist bereits vergeben) |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- Gamma-ray bursts (GRBs) are flashes of gamma-rays resulting from the death of massive stars or the merger of neutron stars. Both are good candidates for neutrino production, and the latter also produce gravitational waves. The presently most prolific GRB detector is the "Gamma-Ray Burst Monitor" (GBM) on the Fermi satellite, containing 12 NaI scintillation detectors. The measured gamma-ray spectra can be fit with either heuristic functions (e.g. cut-off powerlaw) or physical models (synchrotron), but no consensus has been reached about the physical nature of the emission.
This thesis shall investigate a newly developed model, so-called proton synchrotron radiation. This shall be done by creating a large set of template spectra (with existing code), and fit those to the Fermi/GBM data of selected bright GRBs. This model provides a direct route for neutrino production, and thus has interesting implications for IceCube detections.
Technically, this thesis involves (i) learning the basics of GRBs, (ii) data analysis of non-imaging gamma-ray detectors, (iii) understanding and correcting detector effects, (iv) 'big-data' handling wrt. creating many thousands of template spectra, (v) fitting models to data and understanding the underlying (Bayesian) statistics.
Some background in astrophysics is advantegeous. Python knowledge is required, as well as good programming skills.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
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Dunkelmaterie und das "core-cusp" Problem (Thema ist bereits vergeben) |
Beneke |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
- Dunkelmaterie könnte durch eine neue, bisher unbekannte
Teilchensorte erklärt werden. Deren Masse sowie Wechselwirkung sind
aber im Wesentlichen unbekannt. Die einfachste Annahme sogenannter
kalter dunkler Materie beschreibt etliche Beobachtungen
auf Skalen von Galaxien bis hin zu kosmologischen Distanzen,
es verbleiben jedoch offene Fragen auf vergleichsweise
kleinen Skalen, zum Beispiel bzgl. der Verteilung der Dunklen
Materie in Zwerggalaxien (sog. core-cusp Problem). Die Antwort
kann entweder mit unverstandenen astrophysikalischen Prozessen
zusammenhängen, oder aber ein Hinweis darauf sein, dass die
Hypothese von kalter, nicht-wechselwirkender Dunkelmaterie
falsch ist.
In dieser Arbeit wird eine alternative Hypothese untersucht, welche
das core-cusp Problem lösen kann. Durch
eine Wechselwirkung der Dunkelmaterie-Teilchen untereinander
wird im inneren Bereich von Galaxien das Dichteprofil abgeflacht.
Dieser Effekt kann basierend auf grundlegenden physikalischen
Prozessen quantitativ verstanden werden (``Jeans Modell''), was den
Hauptteil der Arbeit darstellt. Zusätzlich hat eine
Selbstwechselwirkung weitere potentiell beobachtbare Konsequenzen,
die diskutiert und untersucht werden sollen.
- Forschungsfeld
- Teilchen und Felder (Theorie)
- Betreuer(innen)
- Mathias Garny
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Durchstimmung der Amplitude des Spin-Hall-Magnetwiderstands (Thema ist bereits vergeben) |
Gross |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
The exchange of spin angular momentum between the localized magnetic moments of a magnetically ordered insulator and the spin polarization of the conduction electrons in an adjacent metallic electrode with large spin-orbit coupling gives rise to interfacial spin mixing. This manifests itself as a characteristic angular dependence of the metal’s resistivity on the magnetization direction of the insulator’s magnetic sublattices, denoted as “spin Hall magnetoresistance (SMR)”. The effect was first observed in ferrimagnetic Y3Fe5O12/Pt thin film heterostructures and recently also reported in antiferromagnetic NiO/Pt and α-Fe2O3/Pt. While the phase of the SMR oscillations is well understood and explained by theory, their amplitude, however, is still a matter of debate, since various extrinsic as well as intrinsic parameters play a crucial role. The goal of this master’s thesis is to study the correlation of the SMR amplitude to the density of magnetic ions and their spin magnetic moments in different magnetically ordered insulating oxides.
We are looking for a master student interested in thin film technology for the fabrication and investigation of magnetic insulator/normal metal bilayer structures. The master project will provide a comprehensive introduction into laser molecular beam epitaxy (laser-MBE) as well as electron beam physical vapor deposition, high-resolution X-ray diffraction (HRXRD), atomic force microscopy (AFM), superconducting quantum interference device (SQUID) magnetometry, photolithography, and angle-dependent magnetotransport measurements.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Matthias Opel
- Stephan Geprägs
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Dynamik im stark korrelierten Hubbard Modell |
Knap |
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Effektive Theorien im Kontext von klassischer Mechanik, klassischer Feldtheorie und Quantenmechanik (Thema ist bereits vergeben) |
Beneke |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
- Das Konzept effektiver Quantenfeldtheorien liegt nach
gegenwaertiger Kenntnis allen fundamentalen Wechselwirkungen
und Beschreibungen der Natur zugrunde. Ziel dieser Arbeit
ist es, dieses Konzept anhand von weniger bekannten
Beispielen aus der klassichen Mechanik, der
klassischen Feldtheorie und der elementaren Quantenmechanik
zu verstehen: a) den Gleichgewichtszustaenden des
invertierten Pendels, b) topologischen Vortexloesungen der
klassischen Bewegungsgleichungen des abelschen Higgs-Modells,
c) dem Delta-Funktionspotential als effektive Beschreibung
von kurzreichweitigen Potentialen in der Schroedinger-Gleichung.
In diesem Beispiel wird auch das wichtige Konzept von
Regularisierung und Renormierung angewandt.
- Forschungsfeld
- Teilchen und Felder (Theorie)
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Effektive Wirkung für Tunnelprozesse in der Quantenmechanik (Thema ist bereits vergeben) |
Garbrecht |
- Arbeitsgruppe
- Theoretische Physik des frühen Universums
- Beschreibung
- Methods from quantum field theory are to be applied to quantum mechanics in order to find loop corrections to tunneling rates. Once the calculations are working, we aim to find situations where these corrections are large and potentially identify condensed matter systems where the pertaining effects are relevant.
- Forschungsfeld
- Teilchen und Felder (Theorie)
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Entwicklung und Test neuer schneller Ausleselektronik fuer kuenftige Beschleunigerexperimente |
Kroha |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- Experimente an kuenftigen Hochenergiebeschleunigern benoetigen wegen der hohen Teilchenkollisionsraten immer schnellere Ausleseelektronik, wobei die Messgenauigkeit nicht beeintraech-tigt werden darf. Verschiende Konzepte dafuer werden derzeit am Max-Planck-Institute in Muenchen entwickeltund in integrierte Schaltkreise (sog. ASIC Chips) in modernster Halbleitertechno-logie ueberfuehrt. Die verschiedenen Stufen der Entwicklung sollen in Bachelor- und Masterarbeiten im Messlabor und auf einsatzbereiten Teilchendetektoren unter den realistischen Betriebsbedingungen getestet werden. Die Testergebnisse fuehren wiederum zu einer Weiterentwicklung der Chips.
- Forschungsfeld
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Erweiterung eines Spektrometers zur Messung der Positronenlebendsdauer in Kaffeebohnen (Thema ist bereits vergeben) |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
Die Messung der Lebensdauer von Positronen (PALS) ist eine etablierte Methode zur Untersuchung von Defekten in kristallinen Materialien oder Nanoporen in Polymeren. Gemessene Positronenlebensdauern betragen normalerweise in etwa 100 ps. Unser PALS Spektrometer besteht aus einem 22Na β+ Strahler und zwei zeitlich hochauflösenden Szintilationsdetektoren deren Ausgabesignale mit einer Rate von 40 GSamples/s digitalisiert werden. Die Verarbeitung der so erzeugten Daten erfolgt offline durch einen Python-Code. Im Verlauf der Bachelorarbeit soll der Versuchsaufbau um zwei Detektoren erweitert werden. Um den Untergrund weiter zu senken soll die Erkennung von koinzidenten γ-Ereignissen im Auswertecode implementiert werden. Nach diesen Verbesserungen wollen wir eine Messreihe zur Porengröße in Kaffebohnen in Abhängigkeit des Röstgrades durchführen. Selbstverständlich sollen daraufhin Messungen an tecnisch relevanten Polymerproben folgen.
- Forschungsfeld
- Festkörperphysik (experimentell)
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Exploring the properties of Quark-Gluon Plasma with anisotropic flow measurements at the Large Hadron Collider |
Fabbietti |
- Arbeitsgruppe
- Dichte und seltsame hadronische Materie
- Beschreibung
- The matter produced in ultra-relativistic heavy-ion collisions resembles the Quark-Gluon Plasma (QGP), which is an extreme state of nuclear matter consisting of deconfined quarks and gluons. Such a state existed in the early Universe, just a few microseconds after the Big Bang. Its properties can be experimentally accessed by measuring the azimuthal anisotropies in the momentum distribution of produced particles in heavy-ion collisions—for instance, in lead-lead collisions reconstructed with the ALICE experiment at CERN’s Large Hadron Collider (LHC).
Of particular interest in this context is the anisotropic flow phenomenon, which is an observable directly sensitive to the properties of QGP. In this project, we introduce the basics of anisotropic flow and corresponding anal-yses techniques, and we guide a student throughout all steps needed for its final measurement, in the large-scale LHC datasets distributed on Grid.
We start a project by briefly introducing a theoretical framework within which an anisotropic flow phenomenon can be defined and quantified. Next, we introduce sophisticated multi-particle correlation techniques, which were developed recently by experimentalists particularly for anisotropic flow mea-surements. We go in detail through the practical implementation of multi-particle correlations (students are expected at this point to perform some simple analytic calculations, and to learn and perform programming tasks both in ROOT and AliROOT. ROOT is the object-oriented analysis frame-work written in C++ programming language, and it is used at the moment as a default software in high-energy physics by all major collaborations world-wide, while AliROOT is the more specific analysis framework developed by ALICE experiment, and which is based on ROOT.)
We wind up the project by letting the student do an independent ani-sotropic flow analysis with his/her own newly developed code in AliROOT, utilizing multi-particle correlation techniques, over real heavy-ion collisions collected by ALICE at LHC, and stored on Grid.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Ante Bilandzic
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Formation and Evolution of the Cosmic Microwave Background: Recombination (Thema ist bereits vergeben) |
Ibarra |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
When the Universe was about 370.000 years old electrons were rapidly captured by protons in the Universe. This process is known as recombination and led to the formation of a flash of light known as the Cosmic Microwave Background (CMB). The CMB is the most powerful cosmological data set to date and its pattern is strongly dependent upon the physics of the process of recombination. The idea of the project will be to revisit the physics of recombination. In particular, studying the ionization processes and cosmological expansion history within the standard cosmological model. In addition, if time allows, the process of recombination when dark matter particles annihilate could be studied, and perhaps the subsequent evolution of the Universe until the first stars begin to form, known as reionization.
- Forschungsfeld
- Teilchen und Felder (Theorie)
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Geometrie eines weißen Rauchers |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
White smokers are likely the cradle of life. Their pores and tunnels allow for pockets of catalytic sites that fuel reactions at the very origin of life. How do these catalytic sites form and grow with the smoker? You will map out the structure of two-dimensional smoker data generated in William Orsi’s lab at LMU. Data will be translated into smoker topology to calculate flows through the smoker. You will learn Matlab, Image Analysis and the fluid physics of laminar flow in flow networks. Prerequisites: Statistical Physics and fascination for the marvels of nature.
- Forschungsfeld
- Biologische Physik (Theorie) (~50%)
- Physik der weichen Materie (Theorie) (~20%)
- interdisziplinäre Themen (Theorie) (~30%)
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Germanium Detektor Entwicklung |
Caldwell |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- Das MPI bietet eine Bachelorarbeit auf dem Gebiet der Germanium
Detektortechnik an. Das MPI betreibt eine Reihe von Prüfständen.
Der erfolgreiche Kandidat wird einige Messungen durchführen
mit neuartigen Germanium-Detektoren durchführen und eine erste Analyse
im Hinblick auf die Detektor-F&E durchführen.
The MPI offers a bachelor thesis in the field of germanium
detector technology. The MPI operates a number of test stands.
The successful candidate will conduct some measurements
with novel germanium detectors and perform a first analysis
with respect to detector R&D.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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GRB Lokalisierung mittels Triangulation |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- Gamma-ray bursts (GRBs) are flashes of gamma-rays resulting from either the death of massive stars (leading to long-duration GRBs) or the merger of two neutron stars (short-duration GRBs). Since the discovery of gravitational waves in conjunction with a short GRB in August 2017, the quest of accurately localizing short GRBs is of utmost importance. Present detectors with good localization capability detect predominantly long-duration GRBs, while detectors sensitive to short GRBs have bad localization accuracy.
We have developed a new concept for GRB light curve cross-correlation using Bayesian model forward-folding, which should provide more accurate localisations for GRBs than previous triangulation methods. The thesis shall take our code and implement it in our existing GRB reduction pipeline for the Fermi-GBM satellite by adding the INTEGRAL/ACS data. This shall allow to rapidly (within minutes) provide accurate localization annuli, providing a proof of concept for the new method. Moreover, comparison with the 30% GRB fraction which is also localized by the Swift satellite, the performance of the new method can be determined.
Technically, this thesis involves learning of (i) data analysis of non-imaging gamma-ray detectors, (ii) understanding and correcting detector effects, (iii) understanding low-count and Bayesian statistics, and (iv) learn about the forward-folding approach for light curve cross-correlation which is independent of the temporal binning of the data.
Some background in astrophysics is advantegeous. Python knowledge is required, and good programming skills and interest in Bayesian statistics are helpful. Joy in data analysis is required.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
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Green photovoltaics |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- The development of organic solar cells is an important achievement of recent years. One of the major advantages of organic solar cells in comparison to silicon-based technologies is the solution-based processability of the active layer. Whereas usually organic solvents are used to dissolve the organic components, we use a water-soluble donor material which allows for an environmentally friendly production process of devices. This project comprises the preparation of active layer films with printing technology and the characterization with spectroscopy methods.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Herstellung von verlustarmen Josephson-Kontakten für Quanten-Bauelemente |
Deppe |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
-
Josephson junctions (JJs) represent a fundamental building block of modern quantum circuits such as superconducting qubits or Josephson parametric amplifiers. The JJs are conventionally fabricated with Al while the surrounding quantum circuits are often made of Nb. Henceforth, there is a need of galvanic connection between them which includes removing Nb oxide via ion milling. As a consequence, one needs to develop a careful milling and fabrication technique in order to preserve a low-loss microwave environment in the close vicinity of JJs. This task is of paramount importance for achieving high coherence times of the related quantum devices.
The goal of this Master project is to develop a fabrication technique for Al/Nb superconducting circuits which will include Ar/O2 milling. This also includes cryogenic microwave studies of fabricated superconducting circuits (such as Josephson parametric amplifiers and transmon qubits) and participation in experiments towards quantum information processing with superconducting devices.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Yuki Nojiri
- Kirill Fedorov
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High efficiency organic solar cells |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Organic solar cells have gained significant improvements via novel organic synthesis methods and optimized fabrication routes, especially with respect to their potential roll-to-roll processing for large-area device manufacturing. Printing technique, such as slot-die printing, allows for up-scaling to industrial-oriented scale, which is not the case for laboratory deposition techniques like spin coating. This experimental bachelor thesis aims at understanding organic solar cell working principle and the corresponding fabrication process of solar cell via advanced slot-die printing technique. Besides, the relationship between its efficiency and morphology will be investigated by different measuring technique, such as AFM and small angle x-ray scattering. The project will involve a literature review, sample preparation process, data analysis and result exhibition.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Hochsensitive Messung optischer Abschwächlängen in Flüssigszintillatoren mit PALM (Thema ist bereits vergeben) |
Oberauer |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- Mit dem existierenden PALM (Precision attenuation length measurement) Aufbau im Untergrundlabor in Garching können optische Abschwächlängen als Funktion der Wellenlänge bis deutlich über 20m gemessen werden. Die Kenntnis der Abschwächlänge ist von fundamentaler Bedeutung für den Aufbau zukünftiger, großvolumiger Detektoren zum Nachweis niederenergetischer Neutrinos. In der Arbeit sollen neuartige flüssige Szintillatoren, die als Target und Nachweismedium in zukünftigen Neutrinoexperimenten eingesetzt werden sollen, mit PALM vermessen werden. Dazu ist es nötig, PALM neu zu justieren und sich mit der Auslesesoftware vertraut zu machen. Die Arbeit wird mitbetreut von Herrn Raphael Stock.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Matthias Raphael Stock
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Hot Spot Population Analysis: indirect search for cosmic accelerators within the IceCube South Pole Neutrino Observatory. |
Resconi |
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Intelligent antibacterial soft templates |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Polyelectrolyte-based block copolymer thin films, where one block possesses biocidal and the other block self-renewal properties, exhibit strong potential as intelligent antibacterial soft templates. As an instance, quaternized acrylate-based films display a 50-fold decrease in the growth of gram-positive and gram-negative bacteria. However, their nanoscale and sub-surface morphology is practically lacking. Recent preliminary results in our group suggest a correlation between presence of charged moieties, solvent annealing as post-preparation step and the corresponding nanoscale film morphology. This bachelor thesis will cover fundamental concepts concerning surface and sub-buried nanoscale morphology of novel unexplored acrylic-based polyelectrolyte block copolymer thin films. The analysis part will cover a survey on the state-of-the-art literature of the field as well as introduction to x-ray scattering data analysis.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Investigating effects of gas humidity on electrical discharge formation in MPGDs |
Fabbietti |
- Arbeitsgruppe
- Dichte und seltsame hadronische Materie
- Beschreibung
- Micropattern gas detectors (MPGD) are a type of particle detectors used in many large high energy physics experiments (Atlas, CMS, Alice) given their easy scalability. MPGDs work by amplifying the primary ionisation signals generated by impeding charged particles as they traverse a gas volume. This amplification of primary electrons is achieved by using structures with micrometer scale patterns that are different for various types of MPGDs, which include Gas Electron Multipliers (GEMs) and Micro-MEsh Gaseous Structure (Micromegas). One of the limiting factors for the long term stable operation of MPGDs is the formation of electrical discharges inside the amplification structures. Due to this, there has been an extensive effort over the years to understand and to develop methods to mitigate these discharges. One of the remaining questions however is how the humidity (the water content) of the used gas mixture affects the formation of discharges in MPDS.
The aim of this project is to conduct the first comprehensive studies investigating the correlation between gas humidity and MPGD discharge stability. For this task, a dedicated detector chamber will be used with modifications to the gas system which enables the precise control of the ambient humidity levels. This venture is a great entry point for anyone interested in particle detector hardware research and development. The achieved results of which might end up shaping the next generation of cutting edge high energy physics experiments
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Berkin Ulukutlu
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Investigating the three-body strong interaction using correlation techniques at the LHC |
Fabbietti |
- Arbeitsgruppe
- Dichte und seltsame hadronische Materie
- Beschreibung
- One of the most compact and dense astrophysical objects in our Universe are the Neutron Stars (NS). The composition of the inner region of the NS is still not known, and several hypotheses have been postulated in the last decades (for a complete review see [1]). Our current knowledge reveals that, beside the neutrons, particles with strange quark content (called hyperons) can be produced. The inner structure and composition of the NS can be modelled by means of Equation of States in which all the fundamental interactions among the constituents are considered. A crucial role to understand the inner structure of the NS is played by the three-body forces among the nucleons and the hyperons. Nevertheless, an accurate microscopic description of the three-body problem is still far to be achieved and precise experimental data to test the existing models are strongly demanded.
The two-body strong interaction among hadrons have been recently explored with femtoscopy studies at the LHC with the ALICE detector (see e.g. [2-3]). The femtoscopy technique analyses the correlation in the momentum space between the particles (e.g. hyperons and nucleons) emitted in proton-proton collisions at the center of mass energy of 13 TeV. The theoretical correlation functions are also calculated, given the interaction potentials or the wave functions of the interacting two-body systems (see [4]). Such powerful analysis technique will be extended to the three-body systems. The candidate student will develop this new analysis method in the case of the three-body interaction between produced particles. Given the interaction potential, the student will calculate the analytical wave function by using the perturbation theory in the context of the non-relativistic Quantum Mechanics and will implement an algorithm in the C++ language that will allow to solve the Schroedinger equation for the three interacting particles. The analysis tools developed in this work will be tested by using the ALICE RUN2 data and will be used to analyse the future RUN3 data (the data taking will start in 2022) that will provide the highest statistic ever in number of events to study the three-body correlations.
To conclude, the proposed work of thesis will serve to the student in developing both the theoretical and data analysis skills; the student will work in the context of an international collaboration and will contribute to extend the femtoscopy technique to the case of the three-body forces among hadrons which are fundamental to unveil the inner composition and structure of one of the most fascinating objects in our Universe.
[1] L. Tolos and L. Fabbietti Prog.Part.Nucl.Phys. 112 (2020) 103770
[2] ALICE Collaboration, Nature, e-Print: 2005.11495 [nucl-ex]
[3] ALICE Collaboration, Physics Letters B 805 (2020), 135419
[4] D. L. Mihaylov, V. Mantovani Sarti, O.W. Arnold, L. Fabbietti, B. Hohlweger et al., Eur.Phys.J.C 78 (2018) 5, 394
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Raffaele Del Grande
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Jet-Oeffnungswinkel von kurzen Gammastrahlenausbruechen (Thema ist bereits vergeben) |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- The coincident detection of gamma-ray emission and gravitational waves from a neutron star - neutron star merger (170817) has been a phantastic confirmation of the 30-year old model for short-duration gamma-ray bursts (GRBs), but also provided a tricky challenge: according to standard theory, we should see gamma-rays only if the observer is within the 5-10 degree wide opening angle of the jet. In contrast, 28 degrees were measured for GRB 170817, contradicting the present concept of beamed radiation in GRBs.
The optical afterglow light curve shows a characteristic curvature from which one can measure the opening angle of the jet. With our seven-channel imager GROND at the 2.2m Max-Planck telescope we have measured such light curves for 2 dozen of short GRBs over the last 10 years. The task of this Bachelor thesis is to fit existing template models to the reduced GROND data, and obtain realistic error estimates of the jet opening angles of the observed GRBs.
The project includes elements from computational and observational optical and high-energy astrophysics, and will allow to obtain extensive knowledge on gamma-ray bursts and gravitational wave detections. Some background in astrophysics is advantageous, but affinity with Python programming is a must.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
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Kalibration eines Röntgendetektors für PIXE und erste Messungen an plasmaexponierten Proben (Thema ist bereits vergeben) |
Stroth |
- Arbeitsgruppe
- Plasmarand- und Divertorphysik
- Beschreibung
p>Particle Induced X-Ray Emission (PIXE) ist eine hochempfindliche ionenstrahlbasierte Methode zum quantitativen Nachweis von mittelschweren und schweren Elementen wie Fe, Ni, Mo, oder W. Die Methode basiert auf der Emission von charakteristischer Röntgenstrahlung bei Beschuss mit Protonen im Energiebereich von einigen MeV. Für quantitative Ergebnisse ist eine individuelle Kalibration des Detektors für jedes interessierende Element notwendig. Im Rahmen der Bachelorarbeit soll ein am 3 MV Tandembeschleuniger des Max-Planck-Instituts für Plasmaphysik neu in Betrieb genommener Röntgendetektor mit Hilfe von dünnen Schichten charakterisiert und für verschiedene Energien kalibriert werden. Mit Hilfe der so gewonnenen Kalibration soll die Deponierung von Metallen (insbesondere Fe, Ni, Cr, Cu) auf Proben aus den Fusionsexperimenten ASDEX-Upgrade und W7-X untersucht werden.
Contact: Dr. Matej Mayer
- Forschungsfeld
- Plasmaphysik (experimentell)
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Low-temperature fabrication of titania films for hybrid solar cells on flexible substrates |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Low-temperature (<150°C) route towards titania films offer promise for simple manufacturing, compatibility with flexible substrates, and titania-based solar cells. Herein, we use a specific titania precursor, ethylene glycol-modified titanate, to fabricate titania films as an electron-transporting layer. This experimental bachelor thesis aims at understanding the working principle of hybrid solar cells and the corresponding fabrication process. Different film characterization will be used such as SEM, GISAXS, XRD, UV-Vis, XPS, etc. The project will involve a literature review, sample preparation process, data analysis and result evaluation.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Measurement of the ΛΦ interaction with femtoscopy studies in pp collisions at ALICE |
Fabbietti |
- Arbeitsgruppe
- Dichte und seltsame hadronische Materie
- Beschreibung
- In low-energy hadronic physics the modeling of the strong interactions among baryons
(particles composed of three quarks) is obtained through effective lagrangians in which the
mediator of the strong forces are typically mesons (particles composed of two quarks).
The interaction amongst strange baryons (so-called hyperons), as Lambdas (Λ), is currently
not well constrained experimentally since these particles are unstable and performing
scattering experiments is extremely challenging.
Hyperon-hyperon interactions though are one of the key ingredients in the physics of
Neutron Stars (NS) in order to understand if these strange particles can be one of the
ingredients present in the core of these dense astrophysical objects.
At the moment, theoretical predictions based on meson-exchange models consider the Φ
meson as the mediator of the strong interaction between two Λs, producing a repulsive
interaction.
However, the coupling between a Λ and Φ is still not measured, hence theoretical
predictions currently rely on symmetry relations to establish the strength.
Recently in the ALICE experiment we used a technique called femtoscopy, which measures
the correlation in the momentum space between two particles, has been used to infer on the
strong interaction of the particle pair.
At LHC a lot of hyperons and mesons, including Λs and Φs, are produced in the collision of
protons at center of mass energy of 13 TeV.
The project will include the identification of Lambdas and Phi particles in the RUN2 data
measured by the ALICE detector in pp collisions through experimental techiques and the
following construction of the main observable: the correlation function.
The study of the obtained ΛΦ correlation function will allow to determine the nature and
strength of the interaction and the comparison with the current theoretical understanding will
allow to shed light on the hyperon-hyperon interaction role inside NS.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Valentina Mantovani Sarti
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Messung der Hautdosis unter Strahlentherapie – insbesondere bei Patienten mit Gewichtsverlust (Thema ist bereits vergeben) |
Wilkens |
- Arbeitsgruppe
- Professur für Medizinische Strahlenphysik (Prof. Wilkens)
- Beschreibung
- In radiotherapy the skin of the patient is naturally spared by the build-up-effect of megavoltage X-ray beams, which avoids side effects like skin irritations or even fibrosis. However, there are some uncertainties to the predicted skin dose: some patients are treated with intensity-modulated radiation therapy (IMRT) using dose calculation algorithms which lack accuracy at the boundary layer i.e. in the skin region of the patient. And some patients suffer weight loss and the irradiated volume shrinks compared to the pre-treatment simulation.
In this thesis you can gain an insight into clinical medical physics and accompany a phantom patient from start (computed tomography for treatment planning) until finish (radiation therapy at the linear accelerator). The goal is to measure accurate skin dose with radiochromic films and to develop a realistic skin model which can also emulate weight loss i.e. volume reduction of a patient. Results can help physicians to estimate realistic skin doses and to decide upon re-planning of treatment plans for patients.
Contact:
Frauke Alexander, frauke.alexander@tum.de, 089-4140-9428
- Forschungsfeld
- interdisziplinäre Themen (experimentell)
- Betreuer(innen)
- Frauke Alexander
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Modelling of the plasma ion heat flux in the edge region of ASDEX Upgrade for an improved understanding of the H-mode access (Thema ist bereits vergeben) |
Stroth |
- Arbeitsgruppe
- Plasmarand- und Divertorphysik
- Beschreibung
Future fusion reactors will have to achieve high plasma temperatures and densities in order obtain high fusion reaction rates, while keeping the energy losses low. These conditions may only be achieved if a state of improved energy confinement - the so called H-mode - is reached. For the success of future tokamaks, such as the currently built ITER, it is critical to understand the access criteria for the H-mode, which are still not fully understood. Recent work concludes that the ion heat flux crossing the edge region of the plasma has to exceed a threshold value. A direct measurement of the ion heat flux is experimentally elusive, however, the electron and ion temperature distribution in the plasma edge is well accessible.
In this work the ion heat flux in the edge will be modelled by using the plasma profiles and the transport code EMC3-EIRENE. Specifically, the effect of heat exchange between electrons and ions will be clarified. In a further step it will be investigated if the ion heat flux can be described by a simplified semi-analytical model.
Contact: Dr. Dominik Brida
- Forschungsfeld
- Plasmaphysik (experimentell)
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Modelling single photon sources for optical quantum circuits (Thema ist bereits vergeben) |
Poot |
- Arbeitsgruppe
- Quantentechnologien
- Beschreibung
For quantum technology it is very important to have sources for single photons. One of the techniques that can be used to create these, is called spontaneous parametric down conversion, or SPDC for short. Here photons with a high frequency can split into two daughter photons with about half the frequency. An important point in this technique is so-called phase matching: the low and high frequency photons should travel at the same speed through the nonlinear material. This is often achieved by using special crystals that have to be oriented carefully. For applications we want to integrated these sources on photonic chips. In this project we will expore the phase matching in waveguides using photonic simulations of waveguides.
- Forschungsfeld
- Nanostrukturen (Theorie) (~50%)
- Optik (Theorie) (~50%)
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Modernes Rechnen, Statistik und Maschinelles Lernen |
Caldwell |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- You will develop novel algorithms in the context of the Bayesian Analysis Toolkit. Possibilities include implementing a Nested Sampling algorithm, developing highly parallelized versions of Markov Chain Monte Carlo algorithms, developing novel test statistics for rare event searches, etc. The specific topic will be decided based on the background and interests of the student.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Multiresponsive Polymermizellen für den medizinischen Wirkstofftransport (Thema ist bereits vergeben) |
Papadakis |
- Arbeitsgruppe
- Physik der weichen Materie
- Beschreibung
- In wässriger Lösung bilden amphiphile Blockcopolymere Kern-Schale-Mizellen. Diese können für den Transport und die Abgabe von medizinischen Wirkstoffen dienen. “Smarte” Systeme werden realisiert, indem die Blöcke durch Temperatur oder pH-Wert schaltbar sind. In der Bachelorarbeit sollen Triblock-Terpolymere aus einem hydrophoben, einem pH-responsiven und einem wasserlöslichen Block mit Fluoreszenz-Korrelationsspektroskopie und dynamischer Lichtstreuung untersucht werden.
Nach einer Literaturrecherche sollen Proben präpariert werden und die Messungen und die Datenanalyse durchgeführt werden. Für weitere Informationen melden Sie sich bitte bei Prof. Christine Papadakis, papadakis@tum.de.
- Forschungsfeld
- Polymerphysik (experimentell)
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Nanodosimetrie in der Neutronentherapie (Thema ist bereits vergeben) |
Wilkens |
- Arbeitsgruppe
- Professur für Medizinische Strahlenphysik (Prof. Wilkens)
- Beschreibung
- The FRM II at TUM has a facility for radiation therapy of malignant tumours using highly effective fast neutrons. Within a feasibility study we want to investigate if nanodosimetric methods can be integrated into a treatment planning software for neutrontherapy.
Nanodosimetry counts ionisations in volumes of the size of a DNA segment and is a promising approach to perform biologically optimized treatment planning.
A fundamental step towards treatment plan optimization are realistic weighting factors for nanodosimetric particle track properties in a voxel geometry i.e. a macroscopic volume used in treatment planning. By comparing simulation results to the result calculated with weighting factors and the known particle spectrum hitting the voxel we want to study if this approach is feasible for treatment planning based on nanodosimetry.
Contact: Frauke Alexander, frauke.alexander@tum.de, 089-4140-9428
- Forschungsfeld
- interdisziplinäre Themen (Theorie)
- Betreuer(innen)
- Frauke Alexander
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Neue Methoden zur Messung der Tau-Masse mit dem Belle II Experiment in Japan |
Caldwell |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- The tau lepton is the least understood lepton of the Standard model. Its short lifetime and decays involving invisible particles make it the most challenging charged lepton to study. The Belle II experiment at KEK in Japan will provide an unprecedentedly large dataset of tau lepton events, enabling highly precise measurements of the properties of this particle. In this project, new approaches to measuring the tau lepton mass will be investigated, making use of simulation studies to explore the potential of this new technique, with possible subsequent applications to real data in longer-term projects.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Frank Simon
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Optoelectronics of tunnelling devices based on single atomic defects (Thema ist bereits vergeben) |
Holleitner |
- Arbeitsgruppe
- Nanotechnologie und Nanomaterialien
- Beschreibung
Structuring materials with atomic precision is the ultimate goal of nanotechnology and is becoming increasingly relevant as an enabling technology for quantum electronics and photonics. The goal of this thesis is to create optically active atomic defects in semiconducting two-dimensional materials, such as MoS2, by helium ion beam lithography with a spatial fidelity approaching the single-atom limit in all three dimensions and to characterize corresponding tunnelling and gate-switching devices. As was demonstrated very recently, such defects can act as single photon emitters with potential applications in quantum communication and sensing. Different layered materials will be combined into few-nm thin heterostructures and they will be integrated into electronic field effect structures to switch the atomic defect states on and off. The material properties will be characterized by different spectroscopies (such as Raman spectroscopy, electron beam and atomic force microscopy). Interest and good knowledge in solid state physics, semiconductor physics, Python programming, optoelectronics or nanofabrication is a plus, but certainly not a must.
- Forschungsfeld
- Nanostrukturen (experimentell) (~40%)
- Festkörperphysik (experimentell) (~20%)
- Quantenoptik (experimentell) (~20%)
- Materialphysik (experimentell) (~20%)
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Optoelectronics of two-dimensional topological van der Waals materials (Thema ist bereits vergeben) |
Holleitner |
- Arbeitsgruppe
- Nanotechnologie und Nanomaterialien
- Beschreibung
- Atomically thin van der Waals crystals form truly two-dimensional materials with remarkable quantum effects. One example is the two-dimensional topological insulator phase, where a two-dimensional sheet of material is insulating, but has conductive one-dimensional edge states. Because of their special topology, these edge states are very robust and can transport both spin and charge, which can find application in quantum information technologies.
The goal of this project is to prepare single atomic layers from novel topological materials (such as MoTe2, WTe2 or HfT5) and to study the topological edge conductivity by optoelectronic microscopy. The material properties will be characterized by different spectroscopies (such as atomic force microscopy and Raman spectroscopy). Different layered materials will be combined into few-nm thin heterostructures and they will be integrated into electronic field effect structures to switch the topological states on and off. Interest or good knowledge in solid state physics, semiconductor physics, Python programming, optoelectronics or nanofabrication is a plus, but certainly not a must.
- Forschungsfeld
- Festkörperphysik (experimentell) (~40%)
- Materialphysik (experimentell) (~30%)
- Nanostrukturen (experimentell) (~30%)
- Betreuer(innen)
- Christoph Kastl
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Ordnung im lebendigen Strömungsnetzwerken (Thema ist bereits vergeben) |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
Der intelligente Schleimpilz Physarum polycephalum ist dafür bekannt, dass er seinen netzförmigen Körper anpasst, um komplexe Probleme zu lösen, wie z.B. den kürzesten Weg durch ein Labyrinth zu finden oder das Problem des Handlungsreisenden zu lösen. Wie kann ein hirnloses Lebewesen solch komplexe Aufgaben bewältigen? Unsere Antwort: mit Hilfe der Physik von Strömungsnetzen. Finde heraus, wie Physarum sein Netzwerk anpasst, indem Du seine Netzwerkarchitektur quantifizierst und nach Skalierungsgesetzen suchst. Vorraussetzung: Statistische Physik. Zu verwendende und zu erlernende Werkzeuge: Matlab-Programmierung, Physik von laminaren Strömungen in Netzwerken, möglicherweise auch Zellkultur- und Hellfeldmikroskopie.
The smart slime mould Physarum polycephalum is renowned for adapting its network-shaped body to solve complex problems like finding the shortest path through a maze or solving the traveling salesman problem. How can a brainless critter accomplish such complex tasks? Our answer: by using the physics of flow networks. Find out how Physarum adapts its network by quantifying its network architecture searching for scaling laws in flow networks. Prerequisite: Statistical Physics. Tools to be used and learned: Matlab programming, physics of laminar flows in networks, potentially also cell culture and brightfieqld microscopy.
- Forschungsfeld
- Biologische Physik (Theorie) (~50%)
- Biologische Physik (experimentell) (~30%)
- Physik der weichen Materie (Theorie) (~20%)
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Partialwellenunitarität und der Dunkelmaterie-Sommerfeldeffekt (Thema ist bereits vergeben) |
Beneke |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
- In many dark matter models with a heavy dark matter particle and a
light mediator, the so-called Sommerfeld enhancement plays an
important role. In some cases, this non-relativistic effect can
modify annihilation cross-sections by orders of magnitude.
Furthermore, zero-energy resonances associated with bound states
are observed for special values of the dark matter mass. In the
vicinity of these resonances, partial-wave unitarity fails and a
consistent and systematic treatment is still to be found.
In this thesis, the student will learn about dark matter
physics and become familiar with the basic
theoretical formalism to calculate the Sommerfeld enhancement
and the associated quantum-mechanicl concepts. This is the
starting point for investigating the restoration of unitarity.
As part of the project, the student shall write a small code
computing the Sommerfeld enhancement by solving a Schroedinger
equation, investigate the various parametric
dependencies and compare the numerical results to known
(semi)-analytic results for several potentials.
- Forschungsfeld
- Teilchen und Felder (Theorie)
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Partikelzerfall-Vertex-Rekonstruktion |
Caldwell |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
The Belle II experiment, situated in Tsukuba, Japan, performs precision measurements of parameters of the Standard Model using decays of B mesons. The MPI Belle II group is very involved in measurements that depend on the decay time of the B mesons. This type of measurements can provide very strong constraints on the Standard Model, and they require a precise knowledge of the position of the B meson decay, the so called B vertex. It is therefore primordial to have an excellent knowledge of the B vertex resolution, and to be able to calibrate it using control channels. The project proposed here will be the development of a calibration method using the decay of D0 mesons to four charged tracks as a control channel. Measuring the resolution on the distance between two pairs of tracks in the D0 decay provides a very useful way to control the vertex resolution using real data. The student will develop the selection and full analysis of this control channel, and his or her results will be an important input for all forthcoming time-dependent analyses at Belle II.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Photoemissionszeitbestimmung an Iodalkanen (Thema ist bereits vergeben) |
Kienberger |
- Arbeitsgruppe
- Laser- und Röntgenphysik
- Beschreibung
- *(English text see below)*
Wir beobachten die Reise eines Photoelektrons durch ein Molekül. Im Rahmen dieser Arbeit werden die grundlegenden Prinzipien der Attosekundenmetrologie und die Anwendung fortgeschrittener Methoden zur Datenauswertung vermittelt. Weiterhin sollen die experimentellen Ergebnisse durch Zuhilfenahme moderner numerischer Methoden interpretiert werden.
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We want to track the journey of a photoelecton through its parent molecule using the tools of attosecond science. In the course of this work, you'll learn about the basic principles of attosecond science, learn to apply advanced data anaylsis methods and you'll aide in the interpretation of the experimental results using state-of-the art numerical methods.
- Forschungsfeld
- Quantenoptik (experimentell)
- Betreuer(innen)
- Christian Schröder
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Polymer thin films embedded with magnetic nanoparticles for applications in magnetic data storage |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Diblock copolymer (DBC) films with periodic nanostructures allows for the precise control of magnetic nanoparticle (NP) arrangement and thus allow for the tuning of the resulting magnetic properties. For potential applications in magnetic data storage, these films should have a large residual magnetization upon removal of a magnetic field and must also be resistant to demagnetization. In this project, we aim to fabricate hybrid films containing both ferromagnetic and antiferromagnetic NPs. The goal is to take advantage of the exchange bias effect that occurs between the two types of NPs, which arises from the pinning of the ferromagnetic domains by the antiferromagnetic domains and leads to a shift in the magnetization curve of the films and an improvement of the desired magnetic properties. An investigation of the surface morphology and inner morphology of the films along with an investigation of the films' magnetic properties shall be the main focus of the thesis work.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Printed ZnO nanostructures |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Assemblies of ZnO nanostructures can enable realization of high-efficient nanodevices with tunable optical, electrical properties as well as a high surface area. Current synthesis routes mainly involve tedious multisteps and also suffer from the limited morphological controllability. To this end, block copolymer-assisted sol-gel synthesis in combination with the industrial-based slot-die printing technique emerges as a promising strategy to construct 3D ZnO architectures with desired morphology and orientation. The morphology-dependent functionalities make ZnO ideal candidates for various applications such as gas sensors, solar cells, light-emitting diodes, energy harvesters and so on. In this work, the mesoporous ZnO thin films with highly tunable morphology will be fabricated and self-assembly pathway during the film formation process will be investigated.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Printing perovskite thin-films for next-generation solar cells |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- In this work, you will manufacture your own printed perovskite solar cells and work part-time in a chemistry lab. Next-generation perovskite solar cells show very high efficiencies competitive to silicon solar cells and have the potential to revolutionize photovoltaics in the near future. The focus of this work will be on printing (slot-die coating) perovskite thin-films. This includes material preparation, optimizing the printing process and analysis of printed films and/or devices. We use imaging techniques (e.g. electron microscopy) and methods for structure and morphology determination, e.g. X-ray scattering.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Qualifizierung von Piezo Motoren by kryogenen Temperaturen für das MADMAX Experiment zur Suche nach dunkle Materie Axionen |
Majorovits |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
Für den Betrieb des MADMAX Experimentes wurden Piezo Motoren entwickelt, die bei kryogenen Temperaturen (4 K) funktionieren und einen Hub von bis zu 1 m haben. Die ersten gelieferten Prototypmotoren müssen bei kryogenen Temperaturen getestet und auf verschiedene Betriebsparameter untersucht werden. Qualification of Piezo motors at cryogenic temperatures for the MADMAX axion dark matter experiment In the context of the MADMAX dark matter axion search experiment Piezo motors have been developed for operation at cryogenic temperatures (4 K) for a stroke of up to 1 m. The first prototype motors that have been delivered will need to be tested at cyrogenic temperatures and several parameters need to be investigated.
- Forschungsfeld
- Teilchen und Felder (experimentell) (~70%)
- Astrophysik (experimentell) (~30%)
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Quantum acoustics in novel piezoelectric multi-layer systems |
Hübl |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
- The field of quantum acoustics aims to investigate quantum mechanical effects in acoustic resonator structures. Combined with e.g. optical and / or superconducting circuits, this offers the possibility to create quantum hybrid systems, which are discussed in the context of storing and converting quantum states. In this project, we shall investigate one of the building blocks, i.e. the surface acoustic wave (SAW) resonator. With your help, we aim to develop and optimize SAW resonators operating in the GHz frequency range with high quality factors and test these devices at moderately low (3-10K) and millikelvin temperatures.
Your bachelor thesis will bring you in touch with state-of-the-art nanofabrication technology and introduce you to microwave spectroscopy tools like vector network analyzers, as well as cryogenic measurement environments. Careful data analysis of the transmission and reflection data of these resonators combined with modeling will put you in the position, to make a meaningful contribution to the creation of quantum hybrid systems.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Rudolf Gross
- Thomas Luschmann
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Raeumliches Model der Roentgenemission vom Galaktischen Bulge (Thema ist bereits vergeben) |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- The recent detection of gravitational waves (GW) with the advanced LIGO/Virgo instruments in conjunction with a short gamma-ray burst (GRB) has surprised astronomers because of the substantially different properties of the GRB signal as compared to canonical GRBs. In addition, deep sky surveys are now attempted in the radio, optical and soft X-ray bands. In order to correlate new transients across different wavebands, and to identify 'unusual' gamma-ray transients, the static part of the sky needs to be described properly.
In two recent Master theses we have developed such a model of the static gamma-ray sky as seen with the Gamma-ray Burst Monitor (GBM) on the Fermi satellite. This model includes the generic gamma-ray background, the Earth albedo, the cosmic ray flux and its modulation through the magnetic field of the Earth. This thesis shall incorporate one additional component, namely the hard X-ray and gamma-ray emission of the Galactic bulge which is the superposition of many spatially unresolved point sources.
Technically, this thesis involves (i) learning the basics of X-ray/gamma-ray astrophysics, (ii) data analysis of non-imaging gamma-ray detectors, (iii) understanding gamma-ray detector effects, and (iv) fitting models to data and understanding the underlying (Bayesian) statistics.
Some background in astrophysics is advantegeous. Python knowledge is required, as well as good programming skills.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
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Role of hole transport layer in the stabilization of perovskite solar cells |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Stabilization of perovskite solar cells is a major challenge toady to bring this new technology into application. We will compare three types of materials as the hole transport layer in combination with Au as an electrode. After understanding the fundamental structure of the related interfaces, the long-time operation stability will be tested at room temperature. In addition, the thermal stability will be tested at elevated temperature such as 85. The project will involve a literature review, sample preparation process, data analysis and result evaluation.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Schaltbare molekulare Flaschenbürsten (Thema ist bereits vergeben) |
Papadakis |
- Arbeitsgruppe
- Physik der weichen Materie
- Beschreibung
- Molekulare Flaschenbürsten bestehen aus einer Hauptkette, an die polymere Seitenarme dicht gepropft sind. Diese können als Träger für Wirkstoffe verwendet werden. Sind die Seitenarme temperatur-schaltbare Polymere, hat deren Konformationsänderung einen großen Einfluss auf die Größe und Form der gesamten Bürste. In der Bachelorarbeit sollen Lösungen solcher Bürsten in Abhängigkeit von der Temperature mit dynamischer Lichtstreuung untersucht werden. Nach einer Literaturrecherche sollen Proben präpariert werden und die Messungen und die Datenanalyse durchgeführt werden. Für weitere Informationen melden Sie sich bitte bei Prof. Christine Papadakis, papadakis@tum.de.
- Forschungsfeld
- Polymerphysik (experimentell)
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Schlaue Nahrungssuche im schlauen Schleimpilz? (Thema ist bereits vergeben) |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
- Der Schleimpilz Physarum polycephalum ist für seine überraschend schlaues Verhalten bekannt. So findet Physarum den kürzesten Weg durchs Labyrinth. Wie schafft das ein Lebewesen ohne Gehirn, ja ohne jegliches Nervensystem? In Deinem Projekt untersuchst du die Bewegung von Physarum bei der Nahrungssuche. Mit Lichtfeldmikroskopie nimmst Du Physarum’s Bewegung auf und analysierst Deine Daten hinsichtlich der Frage ob die Bewegung zufällig oder schlau ist.
- Forschungsfeld
- Biologische Physik (experimentell)
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Search for high energy neutrino emission from blazars: stacking gamma-ray bright sources. |
Resconi |
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Shaping microwave signals for qubit control (Thema ist bereits vergeben) |
Filipp |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
Realization of quantum computers consisting of a few tens of qubits has become a possibility in recent years. In order to do computations, quantum gates must be applied onto qubits and qubit states must be readout. In the Q-Computing lab, qubits are realized using superconducting circuits and quantum gates are applied using microwave pulses. Moreover, the qubits can be readout(measured) using microwave pulses. To generate microwave pulses we use In-phase and Quadrature (IQ) modulation where we use an IQ mixer to mix a continuous microwave tone generated by a microwave signal generator called Local Oscillator (LO) and external IQ signals generated by Arbitrary Waveform Generators(AWGs). This is called up-conversion of a microwave tone. These pulses are then sent to the device situated in a dilution refrigerator. In order to complete the readout process we need to demodulate the readout signal which reflects from the device. For this we use down-conversion of reflected microwave pulse with the help of IQ mixers and LO, and extract IQ signals, which encode the information about qubit state. In this project you will implement both upconversion and downconversion using different IQ mixers and perform calibration of this process. You will learn about microwave pulse generation, IQ modulation, non-idealities in IQ mixers, signal detection and analysis. Therefore, you will gain a practical perspective on the challenges in operating a quantum computer.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Quantenoptik (experimentell) (~50%)
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Simulation der Positronendiffusion zur Bestimmung der Leestellenkonzentration in Festk¨orpern (Thema ist bereits vergeben) |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
- Positronen in Festk¨orpern k¨onnen, je nach Implantationstiefe, zur¨uck an die Oberfl¨ache diffundieren, be-
vor sie annihilieren. Das resultierende γ−Spektrum, insbesondere die Form des 511 keV Annihilationspeak
¨andert sich mit dem Anteil der Positronen die an der Oberfl¨ache annihilieren. Eine Simulation der tiefenauf-
gel¨osten Diffusion erlaubt uns, aus bei unterschiedlichen Implantationstiefen (-energien) gemessenen Daten
die Leerstellenkonzentration im gemessenen Material zu bestimmen. Hauptaufgabe w¨ahrend der Bachelor-
arbeit ist es, die Algorithmen zur numerischen L¨osung der Diffusionsgleichung in Python zu implementieren
und zu validieren.
- Forschungsfeld
- Festkörperphysik (experimentell)
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Simulation und Aufbau einer Überhöhungskavität für hohe optische Leistungen |
Kienberger |
- Arbeitsgruppe
- Laser- und Röntgenphysik
- Beschreibung
- (English see below)
Hast Du Dich schon mal gefragt, was passieren würde, wenn man einen Lichtpuls zwischen zwei Spiegeln einfängt? Genau das wollen wir versuchen und damit die Grenzen der Physik im Bereich der hohen Laserleistungen ausloten. Ziel des Projektes ist eine Verbesserung von MuCLS, einer kompakten, aber brillanten Lichtquelle. Diese liefert Röntgenpulse durch inverse Comptonstreuung von Elektronen an Laserpulsen. Um die Intensität, die Wellenlänge und allgemeine Einsatzmöglichkeiten der Lichtquelle zu erweitern, beschäftigen wir uns mit einem Upgrade der Überhöhungskavität.
Aktuell sind wir dabei das Design des experimentellen Aufbaus zu finalisieren. Deine Aufgabe wird es sein, mit uns das Konzept umzusetzen. Das beinhaltet das Setup aufzubauen und zu testen. Gleichzeitig werden Simulationen durchgeführt werden, zum Beispiel um den Einfluss der Krümmungsradien der Spiegel besser zu verstehen. Die Ergebnisse werden direkt auf die Verbesserung des Aufbaus übertragen. Schlussendlich erhoffen wir uns das erste Mal eine Finesse von 30.000 in der grünen Überhöhungskavität zeigen zu können.
Alles Weitere erfährst Du bei einem persönlichen Gespräch.
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Have you ever asked yourself what would happen if you trap a pulse of light in between two mirrors? This is exactly what we are planning to do and thereby determine the boundaries of high-power laserphysics. The project as a whole is embedded in the frame of MuCLS, a compact but brilliant light source. This light source generates X-ray pulses by inverse Compton scattering of electron on a laser pulse. Upgrading the intensity, wavelength and overall quality of the laser pulse is the goal here in order to extend the range of applications.
Currently, we are finalizing the design of the overall experimental setup. Your task would be to support us in transforming the concept into reality. This includes building the setup and testing it. Meanwhile some simulations on different parameters such as the radius of curvature of the mirrors will have to be performed. The results will directly influence and improve the setup. In the end, we hope to show a finesse of 30.000 in the laser cavity.
If you are interested, feel free to get in touch.
- Forschungsfeld
- Quantenoptik (experimentell)
- Betreuer(innen)
- Albert Schletter
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Source of energy for a gigantic cell |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
Where does the energy for the gigantic cell Physarum polycephalum come from? Physarum is a giant unicellular organism, that can grow up to centimeter-size. The organism behaves intelligently and makes decisions through peristaltic pumping, which drives efficient transport of signals and nutrients throughout Physarums body. To supply every part of its large cell body with energy, it needs a huge number of mitochondria (the powerhouse of the cell). You will develop an assay to clarify the appearance of these organelles using fluorescence microscopy and spectrometry. Moreover, you will get the chance to image the organism and find out where the mitochondria are hidden and how many are there. With that, you might be able to set the foundation for important assumptions about the energy the organism consumes. Prerequisities: Curiosity on how cell biology goes hand in hand with physics and a fascination for uncovering the beauty of nature under the microscope.
- Forschungsfeld
- Biologische Physik (experimentell) (~30%)
- interdisziplinäre Themen (experimentell) (~40%)
- Optik (experimentell) (~30%)
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Spinor-Helizitaetsmethoden und Gravitonamplituden (Thema ist bereits vergeben) |
Beneke |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
- Die allgemeine Relativitaetstheorie ist eine relativistische
Feldtheorie der Gravitation, die aehnlich wie die Elektrodynamik
eine Eichsymmetrie aufweist und deren Feldfluktuationen quantisiert
werden koennen ("Gravitonen"). In den letzten Jahren wurden
erstaunliche Parallelen in den Streuamplituden von Spin-1 und
Spin-2 Teilchen aufgezeigt, deren Ursprung noch unverstanden
ist. Diese werden am unmittelbarsten im sogenannten
Spinor-Helizitaetsformalismus sichtbar.
In dieser Arbeit werden grundlegende Methoden erarbeitet,
um dann mit modernen Werkzeugen wie dem "BCFW shift" die
Konstruktion von Gravitonamplituden zu verstehen. Insbesondere
soll dann das sogenannte "soft theorem" mit verschiedenen
Methoden untersucht und zu verglichen werden. Eventuell kann
eine Bruecke zum Konzept der asymptotischen Symmetrien
geschlagen werden.
- Forschungsfeld
- Teilchen und Felder (Theorie)
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Strahloptimierung zur Messung der Dopplerverbreiterung der Positronenannihilationslinie (Thema ist bereits vergeben) |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
- Unser Dopplerverbreiterungsspektrometer ist ein hervorragendes Werkzeug zur Bestimmung der Defektdichte in Festkörpern. Der monoenergetische Positronenstrahl wird durch das Anlegen einer Hochspannung an die Probe beschleunigt. Die Stahlführung erfolgt durch eine Kombination aus magnetischen und elektrischen Feldern.
Ziel dieser Bachelorarbeit ist es, die optimalen Strahlführungsparameter, d.h. die Einstellungen der Magnetspulen and elektrischen Linsen, für Energien von wenigen eV bis zu mehreren keV zu finden. Die Aufgabenstellung beinhaltet, die automatisierte Optimierung in das Python-Steuersystem zu integrieren, Messungen durchzuführen und diese auszuwerten.
- Forschungsfeld
- Festkörperphysik (experimentell)
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Studien zur Belle-II-Physik |
Caldwell |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
New theoretical studies indicate an up to 5% difference of the calculated cross section from final state radiation on the measurement of the B0 -> K+pi- cross section. The student will implement the new calculations in a Monte Carlo simulation program. The impact will be studies and included in the systematic error and verified in the data.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Study the absorption of antihelium-4 in ALICE experiment at CERN LHC |
Fabbietti |
- Arbeitsgruppe
- Dichte und seltsame hadronische Materie
- Beschreibung
- Dark Matter (DM) is believed to account for roughly 27% of the mass-energy of our Universe, and its nature remains one of the most intriguing unsolved questions of modern physics. This massive hole in our knowledge drives multiple experimental searches for DM, and one of the indirect ways to search for DM is to look for the annihilation or decay of DM particles into ordinary (anti)particles such as light (anti)nuclei as employed by several balloon- and space-borne experiments. Low-energy light antinuclei (e.g. antihelium-4) are particularly promising signals for these indirect DM searches, since the background stemming from ordinary collisions between cosmic rays and the interstellar medium is expected to be low with respect to the DM signal.
In order to reliably estimate the detection probability of interesting events such as DM -> helium-4 + antihelium-4 + ..., the interaction probability of antihelium-4 with ordinary matter (like interstellar medium, Earth's atmosphere) must be measured, since it defines the amount of antihelium-4 particles lost on the way to detector. However, nuclear inelastic cross sections of antihelium-4 + A processes are completely unknown, forcing current estimates of expected antihelium fluxes near Earth to rely on extrapolations and modelling.
The topic of the here advertised master project deals with the measurement of these interactions using the ALICE detector. In heavy-ion collisions at LHC energies (anti)helium-4 nuclei are produced in significant amounts, and unique tracking and PID capabilities of the ALICE experiment make it possible to reliably detect the (anti)helium-4 nuclei in different sub-detector systems. This allows us to quantify the inelastic interaction probability of (anti)helium-4 with the ALICE detector material.
This project will be structured in the following way:
Analysis of the inclusive spectra of helium-4 and antihelium-4 nuclei in PbPb collisions at TeV
Evaluation of the effective antihelium-4 + A inelastic cross sections
Estimation of the antihelium-4 rates expected for different DM models in current and future satellite experiments
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Ivan Vorobyev
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Study the energy dependence of the grain orientation dependent sputtering yields of tungsten and copper |
Stroth |
- Arbeitsgruppe
- Plasmarand- und Divertorphysik
- Beschreibung
Erosion phenomena are an import aspect of the plasma wall interaction occurring in fusion plasma devices. The physical sputtering by impacting projectiles is a long-known and intensively investigated topic. Nevertheless, the dependence of sputtering yield on the grain orientation is often ignored and only studied for a few particular grain orientations. Due to technological progress in the orientation microscopy and a recent development of evaluation software, the energy dependence of this grain orientation dependent sputtering yields can be studied in a systematic way. The aim of the proposed Bachelor thesis is to acquire and evaluate raster electron microscope and height resolved optical microscope data allowing to determine the energy dependence for sputtering of tungsten and copper by gallium ions for all grain orientations.
Contact: Dr. Martin Balden
- Forschungsfeld
- Plasmaphysik (experimentell)
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Suche nach CP-Verletzung in Produktion und Zerfall des Higgs-Bosons mit dem ATLAS-Detektor am LHC |
Kroha |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- Eine wichtige Quelle fuer die Verletzung der CP- und damit der Zeitumkehrsymmetrie koennte in den Produktions- und Zerfalls-mechanismen des Higgs-Bosons zu finden sein. Neue Quellen der CP-Verletzung werden dringend gesucht, um die Existenz von Materie im Universum zu erklaeren. Das ATLAS-Experiment am Large Hadron Collider am CERN bietet die einzigartige Moeglichkeit nach solchen Effekten zu suchen. Dazu werden bereits aufgenommene Daten und Simulationsrechnungen der relevanten Prozesse im ATLAS-Detektor verwendet.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Suche nach doppelt geladenen Higgs-Bosonen mit dem ATLAS- Detector am LHC |
Kroha |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- Doppelt geladene Higgs-Bosonen sind ein eindeutiges Kennzeichen von Erweiterungen des Standardmodells der Teilchenphysik. Elementaren Teilchen mit doppelter wurden bisher noch nicht beobachtet. Die Experimente am LHC bieten die einzige Moeglichkeit nach solchen Teilchen in verschiedenen Produktions- und Zerfallskanaelen zu suchen. Dazu koennen vorhandene Daten des ATLAS-EXperiments im Rahmen von Bachelor- und Masterarbeiten verwendet werden.
- Forschungsfeld
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Suche nach geboosteten Z->e+e- Zerfaellen mit dem ATLAS-Detektor am LHC mit Hilfe von Machine Learning-Methoden |
Kroha |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- In den Zerfaellen neuer schwerer Teilchen am Large Hadron Collider (LHC) treten haeufig stark geboostete Z-Bosonen auf, die in Elektron-Boson-Paare zerfallen koennen. Wegen der starken Buendelung der e+e-Paare werden neue Identifikationsmethoden benoetigt. Vorhergehende Studien im Rahmen einer Bachelorarbeit haben bereits gezeigt, dass mittels Machine Learning eine enorme Erhoehung der Nachweiswahrschein-lichkeit erreicht werden kann. Diese Methoden sollen nun weiterentwickelt und auf die Daten des ATLAS-Experiments am LHC angewendet werden
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Suche nach geladenen Higgs-Bosonen mit dem ATLAS-Detektor am LHC |
Kroha |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- In vielen Erweiterungen des Standardmodells der Teilchenphysik werden zusaetzliche Higgs-Bosonen vorhergesagt, darunter auch geladene Higgs-Bosonen, deren Zerfaelle sich deutlich von denen neutraler Higgs-Bosonen abheben, indem schwere top-Quarks im Endzustand auftreten. Im Rahmen von Bachelor- und Masterarbeiten sollen die verschiedenen Zerfallskanaele und Modelle jenseits des Standardmodells mit Hilfe von Daten und Simulationen des ATLAS-Experiments am LHC untersucht werden.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Suche nach Physik jenseits des Standardmodells in Tau-Zerfällen mit dem Belle II Experiment in Japan |
Caldwell |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- The tau lepton is the least understood lepton of the Standard model. Its short lifetime and decays involving invisible particles make it the most challenging charged lepton to study. On the other hand it is the most promising lepton candidate to display BSM signatures, since its high mass enhances the coupling to new effects in many New Physics models. Recently LHCb obtained results which are in tension with the SM, as there is an indication for Lepton Flavour Violation. The Belle II experiment at KEK in Japan is in a unique position to study the tau and being able to find signatures of dark matter, lepton flavour violation, or both. Several topics can be offered to students in this area, involving Machine learning methods and analysis with Bayesian Analysis tools.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Frank Simon
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Superconducting spintronics with magnetic insulators |
Gross |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
Combining the fields of superconductivity and spintronics can lead to novel functionalities, which mainly arise at the interface of a superconductor and a magnetic material. For example, proximity to a magnetic insulator induces superconductivity with Cooper pair spin triplets. You will be advancing this field by preparing thin film heterostructures of superconductors and magnetic insulators. In addition, within your thesis you will investigate the magnetotransport properties of these heterostructures at low temperatures.
You will work with state-of-the-art thin film deposition machines to carry out this task. Moreover, you will utilize nanolithography for structuring your samples. Furthermore, you will utilize low temperature setups and low noise measurement techniques to gain insight into the interface effects arising at the superconductor/magnetic material interface.
- Forschungsfeld
- Festkörperphysik (experimentell) (~80%)
- Materialphysik (experimentell) (~20%)
- Betreuer(innen)
- Matthias Althammer
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Symmetries of 2D materials and their heterostacks (Thema ist bereits vergeben) |
Holleitner |
- Arbeitsgruppe
- Nanotechnologie und Nanomaterialien
- Beschreibung
- Atomically thin van der Waals crystals form truly two-dimensional materials with remarkable quantum effects. Examples range from semi-metallic graphene to topological insulators and semiconducting materials with a thickness of only few atoms. The goal of this project is to characterize the fundamental symmetries of the underlying crystals and optical properties of such two-dimensional materials determined by optical means including Raman, photoluminescence (PL) and second harmonic generation (SHG) measurements, and to understand their optical properties particularly in two-dimensional heterostacks. The latter allow to build atomically thin field-effect, tunnelling, and photovoltaic devices.
Interest and good knowledge in solid state physics, semiconductor physics, Python programming, optoelectronics or nanofabrication is a plus, but certainly not a must.
- Forschungsfeld
- Nanostrukturen (experimentell) (~40%)
- Festkörperphysik (experimentell) (~20%)
- Materialphysik (experimentell) (~20%)
- Quantenoptik (experimentell) (~20%)
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Tailoring magnon transport in magnetic insulators |
Hübl |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
- By reducing the dimension of materials we can enter into the world of novel quantum classes of materials. Especially, in the limit of 1-dimensional transport, fascinating phenomena like the quantization of transport properties are observed. With your Bachelor thesis you will advance our magnon transport experiments in thin film magnetic insulators by further reducing the lateral dimensions of the magnon transport channel. Utilizing scanning probe microscopy, you will analyze the surface topography of the structured devices, magnetic properties and optimize the fabrication processes.
You will utilize sophisticated nano-lithography in combination with state-of-the-art thin film deposition techniques to constrain the magnon transport channel in magnetic insulators. In addition, you will gain insight into scanning probe microscopy, one of the frontrunners for surface spectroscopy analysis.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Rudolf Gross
- Matthias Althammer
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Test neuer Myondetektoren fuer den Ausbau des ATLAS-Detektors am Super-LHC |
Kroha |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- Die Strahlintensitaet des Large Hadron Colliders wird in den naechsten Jahren um beinahe eine Groessenordnung erhoeht werden, um noch besseren Zugang zu neuer Physik jenseits des Standardmodells der Teilchenphysik zu gewinnen. Fuer die erhoehten Proton-Kollisionsraten an diesem Super-LHC muessen auch die Experimente wie der ATLAS-Detektor noch wesentlich verbessert werden. Hierzu werden am Max-Planck-Institut in Muenchen neuartige Myondetektoren und deren Elektronik entwickelt und gebaut. Bachelor- und Masterarbeiten sollen sich mit dem Test dieser Detektoren befassen, die in der Regel am Institut stattfinden, aber bei hohen Bestrahlungsraten auch am CERN durchgefuehrt werden koennen.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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The Migdal effect and applications to dark matter searches (Thema ist bereits vergeben) |
Ibarra |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
Atoms can be ionized by the interaction of a photon with one of the electrons in the atomic orbitals. As pointed out by Migdal in 1939, atoms could also be ionized by the interaction of a neutron with the atomic nucleus. This process has been revisited recently in the context of dark matter detection. The most common strategy for dark matter detection is the search for nuclear recoils induced by dark matter interactions with the nucleus. However, the Migdal effect could also induce the ionization of the atom, leading to additional (sometimes unique) dark matter signals. In this bachelor thesis the student will calculate the probability of ionization of an atom due to the Migdal effect, and will analyze the implications for dark matter searches.
- Forschungsfeld
- Teilchen und Felder (Theorie)
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Training des neuronalen Netzwerks für einen Spurauslöser beim Belle II Experiment |
Caldwell |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
For the Belle II experiment at the SuperKEKB Collider located in Japan a first level track trigger has been launched recently, based on fast neural network techniques and implemented in Field Programmable Gate Arrays (FPGA). For the new round of experiments in this year, the machine luminosity will be substantially increased, accompanied with much larger expected backgrounds. The task of the thesis is to train sets of neural networks with real data taken by the Belle II experiment under the new conditions, and determine suitable neural architectures, optimized for high track efficiency and powerful background rejection. The resulting set of optimized networks will be implemented in the trigger hardware. Existing program chains for network training and performance analyses need to be mastered, suitably modified and physically exploited under the supervision of experienced physicists within the project.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Ultra-sensitive microwave spectroscopy setup for electron spin resonance |
Hübl |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
- Planar superconducting microwave resonators are key for the ultra-sensitive detection of spin properties. We employ planar microwave resonators fabricated from various superconducting materials like Nb, NbN and NbTiN and test their performance with respect to field and temperature stability. With your help, we aim to improve our resonator design and test their performance with an existing variable temperature setup operating between 1.5 and 300K. You shall further asses the overall performance of the setup using electron spin resonance.
Your bachelor thesis will bring you in touch with state-of-the-art microwave spectroscopy tools like vector network analyzers, as well as cryogenic measurement environments. In addition, you will fabricate and optimize microwave resonators and perform the microwave spectroscopy measurements. Moreover, the careful data analysis of the magnetic field dependent datasets will put you in the position, to make a meaningful impact on novel spin resonance spectroscopy approaches.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Thomas Luschmann
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Ungeordnete Quantensysteme: Vielteilchenlokalisierung |
Knap |
- Arbeitsgruppe
- Kollektive Quantendynamik
- Beschreibung
Disorder has a drastic influence on transport properties. In the presence of a random potential, a system of electrons can become insulating; a phenomenon known as many-body localization (MBL) that has been envisioned by the Nobel laureate Phil Anderson. However, even beyond the vanishing transport such systems have very intriguing properties. For example, many-body localization describes an exotic state of matter, in which fundamental concepts of statistical mechanics break down. In this project we will explore these exciting aspects of many-body localization.
- Forschungsfeld
- Festkörperphysik (Theorie) (~80%)
- Optik (Theorie) (~20%)
- Betreuer(innen)
- Michael Knap
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Untersuchung von Plasmafilamenten am Plasmarand des ASDEX Upgrade Tokamaks (Thema ist bereits vergeben) |
Stroth |
- Arbeitsgruppe
- Plasmarand- und Divertorphysik
- Beschreibung
In Garching wird der Tokamak ASDEX Upgrade betrieben. Darin werden heiße Plasmen magnetisch eingeschlossen. Aber dieser Einschluss ist nicht perfekt und heiße Plasmafilamente werden nach außen in Richtung Wand transportiert. Die Wechselwirkung zwischen Wand und dem heißen Plasma kann die Wand durch Wärmebelastung und Zerstäubung beschädigen.
Die Parameter der Plasmafilamente können mit Langmuir-Sonden und Heliumstrahlemissionsspektroskopie gemessen werden. Letztere Diagnostik misst Linienstrahlung die durch die Injektion von Helium verstärkt wird.
Aufgabenstellung dieser Bachelorarbeit ist es, die Signale der Langmuir-Sonden mit den Signalen der Heliumstrahldiagnostik in Verbindung zu bringen. Dafür soll ein entsprechendes Computerprogramm adaptieren. Mit den daraus gewonnenen Daten sollen Rückschlüsse auf die räumlichen Eigenschaften der Plasmafilamente gezogen werden. Programmiererfahrung (v.a. in Python) wäre vorteilhaft.
Contact: Prof. Ulrich Stroth
- Forschungsfeld
- Plasmaphysik (experimentell)
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Verbesserung der Positionsbestimmung von GRBs |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
Gamma-ray bursts (GRBs) are flashes of gamma-rays resulting from the death of massive stars or the merger of neutron stars. The latter also produce gravitational waves. The presently most prolific GRB detector is the "Gamma-Ray Burst Monitor" (GBM) on the Fermi satellite, containing 12 NaI scintillation detectors. The position is derived by comparing the relative count rates in the differently oriented scintillator planes.
This thesis shall use existing flight data of the brightest gamma-ray source on the sky (the Crab nebula) and improve the spatial resolution of the response matrix of selected detectors. The result shall be tested by localizing selected GRBs with GBM, and comparison against known positions of these GRBs from other satellites (e.g. Swift).
Technically, this thesis involves learning of (i) learning the basics of GRBs, (ii) data analysis of non-imaging gamma-ray detectors, (iii) understanding and correcting detector effects, (iv) fitting light curves with different count statistics, and (v) analyzing and combining large amounts of individual constraints into a coherent picture.
Some background in astrophysics is advantegeous. Python knowledge is required, and good programming skills. Joy in data analysis is required.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
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Vielteilchensysteme mit Zwangsbedingungen |
Knap |
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Wandernde Wellen im Strom (Thema ist bereits vergeben) |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
Waldbrände, eine La Ola Welle aber auch Nervenpulse breiten sich nach den Gesetzmäßigkeiten von wandernden Wellen aus. Das FitzHugh-Nagumo model bietet hier die Möglichkeit die wandernden Wellen theoretisch zu beschreiben. Welchen Einfluß allerdings zusätzlicher gerichteter Antrieb auf die Wellen hat ist unklar. Du wirst mit numerischen Methoden ein erweitertes FitzHugh-Nagumo model implementieren und den Einfluß vom zusätzlichen Strömungsterm erforschen. Analytische Rechnungen verifizieren Deine numerischen Beobachtungen.
- Forschungsfeld
- Biologische Physik (Theorie) (~30%)
- interdisziplinäre Themen (Theorie) (~30%)
- Chemische Physik (Theorie) (~20%)
- Physik der weichen Materie (Theorie) (~20%)
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