Prof. Dr. rer. nat. Susanne Mertens

Courses and Dates

Offered Bachelor’s or Master’s Theses Topics

Analysis of the first KATRIN data and investigation of systematic uncertainties

Scientific motivation: 

What is the mass of the neutrino? This is one of the most fundamental open questions in Astroparticle Physics today. We know from neutrino oscillations that neutrinos must have a mass, but its actual value is still unknown. The knowledge of the neutrino mass would be an important key to understand the formation of structures in the early universe and it could help to shed light on the fundamental origin of masses.

The Karlsruhe Tritium Neutrino (KATRIN) experiment is a direct neutrino mass experiment, which is designed to determine the neutrino mass via a precise measurement of the tritium beta decay spectrum. KATRIN just started data taking in April 2019. The goal is to reach a sensitivity to the neutrino mass of 200 meV after 3 years of data taking. So, right now is the perfect moment to join the experiment!

Thesis Topic:

In this Thesis project you participate in the analysis of the KATRIN data. A key aspect of the analysis is the understanding of systematic uncertainties and their impact on the neutrino mass. 

One of the most critical systematic uncertainties arises from the 10-m long tritium source. The gaseous source can be thought of as a plasma which exhibits a certain plasma potential. In KATRIN, we characterize this electric potential with the help of a krypton calibration source. 

The main task of the Thesis project is the analysis of the krypton calibration campaign. The goal is 1) to determine the key parameters of the source plasma, which are then used as input parameter for the neutrino mass analysis and 2) to  investigate the impact of the associated systematic uncertainties on the neutrino mass fit. You will also have the chance to participate in the actual data taking phase onsite at the KATRIN experiment. 

You will gain & learn: 

• Participate in world-leading experiment to directly determine the neutrino mass

• Learn about astroparticle physics 

• In-depth knowledge on data analysis

• Programming in C++ and Python

• Work in a fun team with lots of social events

suitable as

• Master’s Thesis Nuclear, Particle, and Astrophysics

Supervisor: Susanne Mertens

Characterization of the next-generation TRISTAN prototype detector

Scientific motivation: 

Does there exist an undiscovered type of neutrino, a so-called sterile neutrino? Could this particle be the Dark Matter? These are among the most topical open questions in Astroparticle physics at the moment. 

The aim of the TRISTAN project, is to develop a novel multi-pixel Silicon Drift Detector system to upgrade the KATRIN apparatus. This upgrade would allow the  KATRIN experiment to search for this hypothetical new particle. 

Thesis Topic:

The topic of this Thesis project is the characterization of the next-generation TRISTAN prototype, which will be ready for testing in September 2019. The goal of this project is a detailed understanding of the detector response to photons and electrons. For this purpose you will perform measurements with x-ray calibration sources and with an electron microscope at the Semiconductor Laboratory of the Max Planck society in Munich. For this purpose a dedicated test stand has to be designed and fabricated. The measurements and data analysis will be complemented with detailed Monte Carlo simulations of the particle interactions in the detector and the signal generation. 

You will gain & learn:

• Learn about astroparticle physics 

• Detailed understanding of semiconductor detector technology

• Expertise in experimental hardware work 

• Programming in Python and C++

• Work in a fun team with lots of social events

suitable as

• Master’s Thesis Nuclear, Particle, and Astrophysics

Supervisor: Susanne Mertens