The organization
Nikhef is the national institute for subatomic physics in the Netherlands. At Nikhef, approximately 250 physicists and 80 technical staff work together in an open and international scientific environment. Together they perform theoretical and experimental research in the fields of particle and astroparticle physics. Nikhef is a partnership between six major Dutch universities and NWO-I Foundation, the Institutes Organization of the Dutch Research Council (NWO).
Among the research collaborations Nikhef participates in are the ALICE, ATLAS and LHCb experiments at CERN, the KM3NeT neutrino telescope in the Mediterranean, the Virgo gravitational waves interferometer in Pisa, the Xenon-nT dark matter experiment in Gran Sasso, the Pierre Auger cosmic ray observatory in Argentina, and the eEDM research programme in Groningen. There are also scientific groups on Theory, Physics Data Processing and Detector R&D. Nikhef avails over excellently equipped technical departments in mechanics, electronics and computing.
The Nikhef ATLAS group
The Nikhef ATLAS group consists of a total of 15 scientific staff, typically 5 postdocs and 15 PhD students. As a founding member of the ATLAS collaboration, the group has a long-term involvement in detector construction (the semiconductor tracker, barrel muon chambers, readout, alignment, and data acquisition).
For the phase-2 upgrade (2027-2030), we will instrument and commission one of the end-caps of a new all-silicon inner tracking system (ITk) in Amsterdam, commission the High Granularity Timing Detector (HGTD), and develop the new universal readout system (FELIX) for ATLAS detector systems.
The group also has a strong record in track reconstruction, flavour tagging algorithm development as well as physics data analysis, with a focus on Higgs boson physics, top quark physics, and searches for new physics signatures.
The position
After the discovery of the Higgs boson in 2012, one of the crucial future challenges for the LHC is to probe its most enigmatic property, the Higgs potential, which can manifest itself in LHC collisions through the production of Higgs boson pairs. These decays, which are 1000 times more rare than single Higgs production according to the Standard Model have not yet been observed. Observation of two-Higgs production is one the most important milestone for the LHC physics program, and will help constrain our knowledge of the Higgs potential, which has shaped the universe at its time of creation, and may hold strong clues about the existence of new physics beyond the Standard Model.
This postdoc position will focus on improving selection criteria for two-Higgs production in complex final states, notably HH>bbbb,HH>bbtt decays as well as ttHH production. Emphasis is on the deployment of state-of-the-art machine learning methods where possible, including GNNs, transformer models, both for classification and (mass) regression purposes. The PD role will include coordinating the work of a cohort of PhD students working on di-Higgs analyses, with a focus on advancing object selection, reconstruction, and analysis techniques to significantly boost sensitivity. A key objective is to foster shared development of methodologies across analyses, ensuring alignment and synergy with parallel efforts, particularly those implying machine learning. This postdoc position is co-supervised by dr. Flavia de Almeide Dias and dr. Clara Nellist. The position is based at Nikhef and the candidate is employed by the University of Amsterdam.
The position offered here are part of a NWO-funded physics program “The potential of the Higgs boson”, which will ultimately comprise 7 PhD positions and 2 postdoc positions in the Nikhef ATLAS group in the period 2025-2030 all focused on the Higgs boson potential, complemented by 9 Nikhef staff scientists that offer supervision, networking opportunities and a specialized training program in data analysis techniques and Higgs boson physics.
Requirements
We are looking for postdoctoral candidates with an (almost) completed PhD degree in high-energy physics. The ideal candidate has a strong track record in data analysis, has good software skills, several years of research experience in experimental particle physics, and significant experience with the application of machine learning algorithms in data selection in particle physics.
Offer
We offer a temporary employment contract for 38 hours per week for a period of 36 months, with a probationary period of two months. The preferred starting date is to be discussed. The gross monthly salary, based on 38 hours per week and dependent on relevant experience, ranges between € 3,458 to € 5,486 (scale 10). This does not include 8% holiday allowance and 8,3% year-end allowance. The UFO profile Postdoctoral Researcher is applicable. The Collective Labour Agreement of Universities of the Netherlands is applicable.
Application
Qualified applicants are encouraged to apply by filling in the template below. The deadline for applications is June 10th, 2025. Please be prepared to upload a short cover letter, a curriculum vitae and have the email address of at least three referees ready who are willing to send a letter of recommendation on your behalf. A knowledge security check can be part of the selection procedure.
Please indicate in which position(s) you are interested in your cover letter. Interviews with selected candidates are foreseen in the week of July 1st. For further information, feel free to contact list co-supervisors for details on the positions, or prof. dr. Wouter Verkerke for general information about the Nikhef ATLAS group.
About the University of Amsterdam
The Faculty of Science has a student body of around 8,000, as well as 1,800 members of staff working in education, research or support services. Researchers and students at the Faculty of Science are fascinated by every aspect of how the world works, be it elementary particles, the birth of the universe or the functioning of the brain. The Institute of Physics (IoP) is located in the centre of the Amsterdam Science Park. The IoP – as part of the Faculty of Science – is housed in a modern building with excellent labs and technical facilities. Surrounded by several national research institutes and with our partners at the Vrije Universiteit Amsterdam, the institute is part of a strong physics centre of international standing. One of the institutes that the IoP has very close ties to is Nikhef, the national institute for subatomic physics in The Netherlands. The present vacancy is fully embedded in the ATLAS group of Nikhef.
The UvA is an equal-opportunity employer. We prioritise diversity and are committed to creating an inclusive environment for everyone. We value a spirit of enquiry and perseverance, provide the space to keep asking questions, and promote a culture of curiosity and creativity.
By applying to this position through the Nikhef portal, the candidate also gives permission for the application information to be used by the University of Amsterdam.