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Prof. Dr. rer. nat. Stefan Schönert

Photo von Prof. Dr. rer. nat. Stefan Schönert.
Telefon
+49 89 289-12511
Raum
PH: 3053
E-Mail
schoenert@ph.tum.de
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Visitenkarte in TUMonline
Arbeitsgruppe
Experimentelle Astroteilchenphysik
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Lehrveranstaltungen und Termine

Titel und Modulzuordnung
ArtSWSDozent(en)Termine
Mentorenprogramm im Bachelorstudiengang Physik (Professor[inn]en L-Z)
Zuordnung zu Modulen:
TT 0.2 Märkisch, B. Müller-Buschbaum, P. Oberauer, L. Papadakis, C. Paul, S. … (insgesamt 18)
Leitung/Koordination: Höffer von Loewenfeld, P.
FOPRA-Versuch 02: Messung der Radonkonzentration in Raumluft
Zuordnung zu Modulen:
PR 1 Schönert, S.
Mitwirkende: Pollmann, T.
FOPRA-Versuch 17: Mößbauer-Effekt
Zuordnung zu Modulen:
PR 1 Schönert, S.
Mitwirkende: Wagner, F.
FOPRA-Versuch 63: Gammaspektroskopie
Zuordnung zu Modulen:
PR 1 Schönert, S.
Mitwirkende: Heiss, B.
FOPRA-Versuch 77: Detektorphysik (Simulation und Experiment)
Zuordnung zu Modulen:
PR 1 Schönert, S.
Mitwirkende: Klenze, P.
Neutrinos and Dark Matter in Astro- and Particle Physics Colloquy
Zuordnung zu Modulen:
KO 2 Majorovits, B. Mertens, S. Resconi, E. Schönert, S. Weiler, A. Mo, 10:30–12:00
Vorbesprechung zum Fortgeschrittenen-Praktikum (F-Praktikum)
Zuordnung zu Modulen:
PR 0.1 Schönert, S. Stutzmann, M.
Mitwirkende: Hauptner, A.
einzelne oder verschobene Termine

Ausgeschriebene Angebote für Abschlussarbeiten

Dark Matter search with sensitive cryogenic detectors

The CRESST (Cryogenic Rare-Event Search with Superconducting Thermometers) experiment operated at the Gran Sasso underground laboratory employs highly sensitive cryogenic detectors to the search for signals of the elusive dark matter particles in CaWO4 crystals. The energy thresholds of less than 100 eV reached in the current experimental run, CRESST-III Phase 1, are the lowest in the field, making CRESST the most sensitive experiment to light dark matter. Changes in the geometry of the tungsten thin-film thermometer promise still a factor two improvement in energy threshold, which could signicantly boost the physics reach of CRESST-III Phase 2. A Master's student can contribute to the design and prototyping of the new thermometers as well as characterisation of the new CRESST detectors in Munich. Deploying the detectors in the main setup at Gran Sasso could be the culmination of the thesis work.

Within the master thesis you would

  • become acquainted with superconducting transition-edge sensor (TES) technology
  • participate in the clean-room production of the sensors
  • be introduced to the operation of dilution refrigerators as well as cryogenic detector operation and analysis
  • participate in the operation of the main experiment at Gran Sasso

If you are interested, please contact: 

Prof. Stefan Schonert, E15 schoenert@ph.tum.de +49 89 289-12511

and 

Dr. Federica Petricca, MPP petricca@mpp.mpg.de +49 89 32354-309

geeignet als
  • Masterarbeit Kern-, Teilchen- und Astrophysik
  • Masterarbeit Applied and Engineering Physics
Themensteller(in): Stefan Schönert
Search for the creation of matter without the balancing anti-matter: improving the liquid argon scintillation light detection in GERDA and LEGEND

According to the Standard Model of particle physics, the difference in the number of leptons and antileptons is conserved in nuclear reactions. Every radioactive decay should therefore produce both leptons and antileptons symmetrically, thereby keeping the total lepton number constant. Given that neutrinos do not carry electric charge, they could be their own anti-particles, usually referred to as Majorana particles. From neutrino oscillation experiments we know that neutrinos are massive particles and it is very plausible that they are of Majorana type, violating lepton-number conservation, and connect to a sector of right-handed (sterile) heavy states. The decay of these heavy particles in the early universe could produce the cosmic matter-antimatter asymmetry (baryogenesis by leptogenesis). The most powerful way to demonstrate the Majorana nature of neutrinos is by the observation of neutrinoless double beta decay (0νββ), a nuclear decay that explicitly violates lepton-number conservation. Two electrons (matter) are created in this proposed nuclear process without the emission of anti-neutrinos (anti-matter). Neutrinoless double beta decay would also contribute to our understanding of the absolute mass scale of neutrinos, complementary to endpoint measurements of the tritium beta decay and to cosmological observations, and would provide guidance for the construction of neutrino mass models.

We are currently operating the GERDA experiment at the Italian Gran Sasso Laboratory, which has the strongest sensitivity worldwide, and are preparing the new LEGEND experiment. In both experiments, bare germanium detectors are operated in liquid argon which serves as a high-purity coolant and as an active veto system.

This master thesis would focus on the development and operation of the liquid argon veto system to discriminate signals from backgrounds. As a master student, you would

  • be involved in the development and testing of novel light detectors 
  • analyse and model the experimental signals
  • learn about modern detector technologies 
  • participate at the upgrade and commissioning of the system at the Gran Sasso underground laboratory. 

The chair of astroparticle physics has traditionally a high fraction of female bachelor, master and PhD students, and we strongly encourage our female KTA master students to apply. 

 
geeignet als
  • Masterarbeit Kern-, Teilchen- und Astrophysik
  • Masterarbeit Applied and Engineering Physics
Themensteller(in): Stefan Schönert
Searching the needle in a haystack, or rather: is the neutrino a Majorana particle?

GERDA is data taking at the italian Gran Sasso laboratory searching for one of the rarest process in nature: neutrinoless double beta decay. We try to unravel whether particles can be created without being balanced by anti-particles. Such a process is not allowed by the Standard Model of Particle Physics and if observed, would require that the elementary neutrino particle is identical with its anti-particle, or alternatively, point to new interactions that violate lepton number conservation. In this project you would would focus on the data analysis and develop and optimize an analysis strategy to decipher background from signal events. 

Concrete, you would study events created by  K42/Ar42 beta decays, penetrating the n-plus deadlayer of a high-purity germanium diode and create so called slow-pulses. You would start with a data set from calibration data available. First you would learn to apply the standard cuts to create distributions of these slow-pulse events. Then you would try alternative methods and develop novel algorithms which try to extract the maximum information based on the physics process of the signal and compare the separation capabilities with the standard methods. You could also try to model the signals to get a deeper understanding, which in turn might be useful to devise an optimal analysis strategy. This could include deep learning and neural networks techniques. You should be familiar with or willing to learn C/C++, the linux command line interface, scientific programming, and statistics. The work takes place within an international collaboration and there will be many opportunities to practice presenting your analysis results to other physicists.

geeignet als
  • Bachelorarbeit Physik
  • Masterarbeit Kern-, Teilchen- und Astrophysik
  • Masterarbeit Applied and Engineering Physics
Themensteller(in): Stefan Schönert
Telling signal from background in a liquid argon dark matter detector

he DEAP-3600 Dark Matter detector has been taking data for more than a year now, and now is a unique opportunity to join the analysis effort of the quickly growing dataset.  DEAP searches for interactions of dark matter particles in a liquid argon target. The TUM group focuses on elimination of the most prominent background, namely background from electromagnetic events. Thesis topics include the study of rare coincidences which could fool the background suppression algorithm, study of the performance of different suppression algorithms over many months, developing statistical models to estimate the probability of mis-characterizing a background for a signal event, and investigation of the effect of the trigger efficiency on the background suppression power. Students should be familiar with or willing to learn C/C++, the linux command line interface, scientific programming, and statistics. The work takes place within an international collaboration and there will be many opportunities to practice presenting your analysis results to other physicists.

geeignet als
  • Bachelorarbeit Physik
  • Masterarbeit Kern-, Teilchen- und Astrophysik
  • Masterarbeit Applied and Engineering Physics
Themensteller(in): Stefan Schönert
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