We are currently looking for a
PhD candidate
to join our team at Nikhef and the University of Amsterdam to work on the study of the top quark with the ATLAS experiment at CERN.


The Nikhef organisation
Nikhef is the national institute for subatomic physics in The Netherlands. The University of Amsterdam is one of the six major Dutch universities that constitute the institute together with the Dutch Foundation for Scientific Research (NWO). At Nikhef, approximately 190 physicists and 80 technical staff members work together in an open and international scientific environment. Together, they perform theoretical and experimental research in the fields of particle and astroparticle physics.

The Nikhef ATLAS group
The Nikhef ATLAS group consists of groups in Amsterdam and Nijmegen, for a total of 15 staff, and typically 5 postdocs and 20 PhD students. As a founding member of the ATLAS collaboration, the group has a long-term involvement in both detector construction (the semiconductor tracker, barrel muon chambers, readout, alignment, and data acquisition) as well as operations (trigger and muon tracking reconstruction). For the phase-2 upgrade (2025-2027), we will assemble and commission one of the end-caps of a new all-silicon inner tracking system (ITk) in Amsterdam and develop a new universal readout system (FELIX) for all ATLAS detector systems. The group also has a strong record in physics data analysis, with strong focus on Higgs boson physics, top quark physics and machine-learning assisted searches for new physics signatures. Nikhef also hosts an ATLAS Tier-1 data processing center, and offers substantial additional computing resources for end-user data analysis and simulation.

Description of the project
As a member of our team, you will have the opportunity to contribute to the ongoing efforts to understand the properties of the top quark, the heaviest elementary particle in the Standard Model. In particular, you will work on analysing the four-top-quark production. This exciting new process in particle physics was recently observed directly for the first time by both the ATLAS and CMS collaborations using data from collisions during Run 2 of the Large Hadron Collider. This is one of the rarest and most massive events measured in ATLAS so far; it has a production rate 70,000 times lower than top quark–antiquark pairs, making it an extremely challenging detection problem.

There are many exciting avenues to take with this analysis during Run 3 of the LHC to search for signs of new physics phenomena. These include:
  • the implementation of new machine learning algorithms to further improve the isolation of the 4 tops signal and look for anomalies
  • the development of advanced analysis techniques and statistical models to extract precise measurements of the properties of the top quark using Effective Field Theory and improve the measurement of the coupling of the top quark to the Higgs boson.

Requirements
We are looking for a candidate with a (almost) completed master degree in high-energy physics, or a closely related field.
The ideal candidate has a strong interest in data analysis, has good software skills (C++, python, ROOT) and has (some) research experience in experimental particle physics. Please note that experience in theoretical physics is *not* required, all theory required will be taught and developed during the PhD.

Offer
A temporary contract at the University of Amsterdam (UvA) for 38 hours per week for the duration of 4 years (the initial contract will be for a period of 18 months and after satisfactory evaluation it will be extended for a total duration of 4 years). The preferred starting date is negotiable and ideally before the end of 2023. This should lead to a dissertation (PhD thesis). We will draft an educational plan that includes attendance of courses and (international) meetings. We also expect you to assist in teaching undergraduates and master students. We offer a PhD position based in Amsterdam, with the possibility to stay at CERN for a period of up to 1 year.

The gross monthly salary, based on 38 hours per week and dependent on relevant experience, ranges between € 2,541 to € 3,247 (scale P). This does not include 8% holiday allowance and 8,3% year-end allowance. A favourable tax agreement, the ‘30% ruling’, may apply to non-Dutch applicants. The Collective Labour Agreement of Universities of the Netherlands is applicable.

Application
Qualified applicants are encouraged to apply by clicking the 'solliciteer' button below. Please be prepared to upload a curriculum vitae and have the email address of at least one referee ready who is willing to send a letter of recommendation on your behalf. 
The deadline for applications is June 15th, 2023. Further information on this position can be obtained from dr. Clara Nellist (clara.nellist@cern.ch)
Solliciteer
 
Bovenaan