If you found our research intriguing and want to join the team please reach out to Prof. Dr. Martin Fertl at jobs-agfertl@uni-mainz.de.
We currently have the following positions to fill:
You're interested in a bachelor or master theses in experimental nuclear physics? Maybe you want to check out this presentation for a quick overview of the experiments. Please reach out to Prof. Dr. Martin Fertl at anytime at jobs-agfertl@uni-mainz.de.
Open master/bachelor thesis projects:
For tSPECT:
Title: Magnetic field shaping by 3D-printed pole caps
Goals: The aim of this project is to smooth intrinsic and extrinsic magnetic field distribution of permanent magnets via pole caps. Therefore, arrays of a small number of commercial permanent magnets are scanned with Hall-probes and the influence of pole caps of varying thickness are probed by experiment, simulation and compared to available theory. Two effects are expected, one is a decrease of the magnetic flux density, which is well described by magnetostatic shielding expressions. The other is a less investigated smoothing effect of inhomogeneities. In this project, experimental data is compared to simulations with the aim to find analytical expressions to predict and shape the field. Two different ferromagnetic materials are tested, one of which can be 3D-printed. The findings may have direct consequences for the magnet design in several running research programs and high likelihood to be part in a future publication.
Software used: Programming languages Python and/or GNU Octave, FEM-software: COMSOL Multiphysics and FEMM, CAD-programs for 3D-printers
For Project 8:
Title: Electron trap design for Project 8
Goals: Simulation and design of an electron trap for cyclotron radiation emission spectroscopy.
This project aims at optimizing the magnetic bottle shape and volume in order to control
the motionally induced frequency side bands of a CRES signal. This shall allow to
improve the number of detectable elctrons in the magnetic bottle observed by a
phased antenna array CRES detector.
Prerequisites: Curiosity, solid interest in particle tracking simulation, basic knowledge of Python and/or C++
Title: Electron trap design verification for Project 8
Goals: A precison characterization of the magnetic field generated by different coil geometries that can
be applied as an electron trap in the Porject 8 experiment. This includes the production of precision
coils, working with Hall Probe sensors, 3D-motion-controlled tables, precission power supplies,...
Prerequisites: Curiosity, solid interest mechanical and electronics projects relating to precision magnetic fields
Title: Magnetic field mapper
Goals: Inside the cryogenic environment (~ 4K )of the Project 8 experiment the precision magnetic field needs to be mapped with part-per-million resolution in the radiactive decay volume. We want to perform a study of the best combination of magnetometry and positioning technology to allow for such an in-situ measurement of the 3D magnetic field map.
Prerequisites: Curiosity, solid interest mechanical and electronics projects relating to precision magnetic fields
For Muon g-2:
Bachelor thesis project
Description: The magnetic field in the muon g-2 experiment is measured using NMR techniques. Therefore an RF pulse send to a small coil surrounding a proton rich sample flips the sample magnetization out of equilibrium and the induced current in the coil due to spin precession is digitized. The precessing and relaxing signal called an FID is analized and the precession frequency is extracted. The magnetic field is expressed in terms of the precession frequency. For analysis a spatial and temporal interpolation between the measurement has to be performed. Key for the iterpolation to work is that each measurement is of good quality, e.g. the extracted frequency comes from a good signal to noise measurement, and the fit quality is good. Two different systems are used in the g-2 experiment which are the Trolley system, a movable device carring 17 probes that are pulled through the ring every 3 days, and a fixed probe systems with ~380 probes located in the walles of the vacuum chambers. The task of the student is to develop general, robust quality cuts on the extracted frequency that go into analysis. The improved quality cuts will go into the analysis of Run4/5/6 data processing and analysis.
Data analysis: Programming languages python and C++ (optional)
Master thesis project
Description: The muon g-2 experiments measures the magnetic field using NMR techniques. It relies on the free induction decay (FID) signal that is recorded using a pick-up coil around a proton rich sample after bringing the magnetization oft he sample out of equilibrium by an induced RF pulse to the same coil. The free induction decay is an exponentially damped oscillation signal where the frequency corresponds to the spin precession frequencies of the protons in the sample. This quantity is used to express the magnetic field in muon g-2 experiment. The exponential damping comes from decoherence of the signal. By applying a second RF pulse that inverts the magnetization a re-cohering of the magnetization can be achived called the spin echo. We like to develop and implement a frequncy extraction from this spin echo signal. We already recorded data at a test magnet and are ready to take measurements at the muon g-2 magnet. We would like to cross-check the calibration of our probes using this new technique and check for consistency with the FID method.
Data analysis: Programming languages python and C++ (optional).
You don't know yet if experimental physics is your passion? You want to work with us a a HiWi! We always have small technical projects that directly relate to our larger experimental setups. Maybe you want to check out this presentation for a quick overview of the experiments.
Just reach out to Prof. Dr. Martin Fertl at jobs-agfertl@uni-mainz.de.