Thesis and job opportunities
It is possible to join the group by doing internships or writing a bachelor/master thesis. Requirements, contact information and the latest available topics can be found below.
General topics
The STYX experiment is part of the Master lab. course. It uses straw-tube detectors from the ZEUS experiment to measure the properties of cosmic rays. These are the same basic detector elements as those used in the ATLAS TRT. The detector also allows students to become familiar with operating many aspects of a particle-physics detector from testing to calibration and track reconstruction. New ideas for the tracking include the use of a Hough transformation for track finding. Studies and improvements to the setup of the experiment include implementing a new readout board, which would allow measurements over a larger area, a redesign of the trigger, powering and readout connections and improvements in the calibration tools.
The particle flow algorithm in ATLAS has been developed to improve the energy resolution of hadronic objects (jets, taus, missing transverse energy), which are a key ingredient for many physics analyses. The idea of the particle flow algorithm is to replace the energy deposited by the charged particles in the calorimeters by the momentum determined by the tracking system; exploiting the fact that the tracker has better resolution than the calorimeter for low transverse momentum. During Run 3 it is planned to extend the current algorithm to include electrons, photons and mouns as particle flwo objects.
Machine learning tools are finding more and more applications in particle physics analyses. Our group has many years of experience in using such techniques and has built up a framework that is used in many different analyses. The framework enables students to get started rapidly in using such tools. Areas where theses could be written include the development and comparison of different machine-learning techniques in ATLAS single top physics analyses; electron and photon identifcation; tau lepton mis-identification (fakes).
Measurement of the single top quark production in association with heavy bosons:Single top-quark production has been measured for the first time by the Tevatron experiments CDF and D0. The LHC experiments ATLAS and CMS were able to observe the production with much less data, thanks to the larger cross-section at higher energies. The coupling between a top quark and the Higgs boson is a key measurement that is planned to be made with the data from LHC Run 2 and/or 3. If the Higgs boson coupling is exactly as predicted in the Standard Model, the production of a Higgs boson in association with a single top quark is expected to be very small. However, non-standard couplings could enhance the cross-section significantly. As a first step towards a measurement of tH production, tZ production is being studied. Such a measurement allows the techniques to be developed and optimised.
Single top-quark production has been measured for the first time by the Tevatron experiments CDF and D0. The LHC experiments ATLAS and CMS were able to observe the production with much less data, thanks to the larger cross-section at higher energies. The coupling between a top quark and the Higgs boson is a key measurement that is planned to be made with the data from LHC Run 2 and/or 3. If the Higgs boson coupling is exactly as predicted in the Standard Model, the production of a Higgs boson in association with a single top quark is expected to be very small. However, non-standard couplings could enhance the cross-section significantly. As a first step towards a measurement of tH production, tZ production is being studied. Such a measurement allows the techniques to be developed and optimised.
Internships
Students (6th semester and above) who already attended the Lecture on Particle Physics and the Advanced Laboratory Course have the opportunity to join the group and work full time for three or four weeks on high energy particle physics and get acquainted with the research topics and analysis methods used in the group.
At the beginning of the internship, an introduction to the research topics of the group is given. The group members also explain the software framework to be used. The student works on an analysis with the support and advice of the group. The student will learn how to use data analysis methods to study high energy particle interactions. Some time for the investigation of own questions related to the research topic is also given. The last part of the internship consists in the presentation of the results to the group.
Bachelor Thesis
Motivated students have the opportunity to join the group and work in high energy elementary particle physics in the context of the ATLAS international collaboration.
Requirements: The topic of the bachelor thesis will be assigned when at least 90 points have been collected in the bachelor studies. It is possible to begin the bachelor thesis already in the 5th semester. The bachelor thesis should be finished within a maximum of 4 months.
Recommended knowledge: Successful participation in the courses:
" Introduction to EDP ", " Numerical Methods in Physics " and " Physics V: Nuclei and Particles "
Topics: The topics available are closely related to those offered for Master theses.
Master Thesis
We have open positions for master students to write their thesis in various research fields in high energy physics. The topics and the details are listed below.
Requirements: A good knowledge of particle physics is essential and at least basic programming skills are required. Solid programming can be very useful. The master thesis should be finished within 1 year. The students should first choose a topic and then perform a detailed analysis on the specified subject. The results of the studies will then be documented in the form of a master thesis. During their 1-year period, the master students are encouraged to take part in tutoring the physics lectures.
