Post-doctoral fellow in Particle- and Nuclear Physics

Post-doctoral Fellow in Particle- and Nuclear Physics

Lund University was founded in 1666 and is repeatedly ranked among the world's top universities. The University has around 46,000 students and 8,500 staff based in Lund, Helsingborg, and Malmö. We are united in our efforts to understand, explain, and improve our world and the human condition.

This postdoc position will be part of the Lund LDMX group, LunDMX, embedded in the Division for Particle and Nuclear Physics at the Physics Department. The division, with about 60 employees, comprises a lively mixture of active research in theoretical and experimental particle and heavy ion physics as well as experimental nuclear physics. The experimental particle physics activities include research at the well-established LHC experiments ATLAS and ALICE as well as efforts to realize new, creative experiments like HIBEAM/NNBAR at ESS and – most relevant for this project – LDMX at SLAC ((Use the "Apply for this Job" box below).).

We exploit synergies across these projects, and our contributions include detector development, trigger and DAQ, physics and performance analysis as well as software development and computing. The LunDMX group currently consists of a postdoc, three faculty members, and three Ph.D. students, and an engineer. This postdoc position is an important addition to our group, it will inject additional momentum to our work and strengthen our impact on the overall LDMX project.

This position is also to serve as a stepping stone for the successful candidate, with ample opportunity for career development, for which we strive to give all the support we can.

The Light Dark Matter eXperiment is a fixed-target experiment planned at SLAC with the main purpose of searching for sub-GeV thermal-relic dark matter particles produced from an 8 GeV electron beam impinging on a thin target. The Lund LDMX group (LunDMX) contributes to physics analysis, detector development and performance studies as well as software development and computing. In addition, we are active in addressing sustainability questions related to developing a new particle physics experiment.

The overarching theme of this project is to get ready for LDMX data, and the work will be conducted in close connection with the international LDMX collaboration, in which Lund University is currently the only non-US participant. The main priority in this project will be to study the capabilities of LDMX to handle pile-up (multiple electrons hitting the target at the same time) in more detail.

This will be based on simulation studies of potential backgrounds, detector performance, and physics sensitivities. One concrete example is the use of different codes for simulating critical backgrounds, comparing these predictions and developing methods for how to measure these backgrounds in data. The project also aims to explore to which extent machine learning methods can help with these tasks, e.g. object reconstruction and signal/background discrimination.

This will be a focus in the project.

One exciting milestone for LDMX is the detector prototype system test with cosmic muons planned at SLAC in 2026. If the candidate is interested, there will be the opportunity to contribute to the analysis of this test data, mainly from the prototype of the hadronic calorimeter. Closely related to this, there is also the possibility to contribute to the characterization of the HCal electronics with a test stand locally in Lund.

There is some flexibility in the research programme for this position, and details can be tailored to your specific interests and expertise. There will also be the opportunity to work with questions of climate sustainability in LDMX/HEP.

As a postdoc in the LunDMX group, you will mainly perform simulation-based studies of different aspects feeding into the physics potential of LDMX. This will require the use (and further development) of different simulation tools, mainly the GEANT4-based ldmx-sw framework (), written in C++, maintained on github and configured via python. You will work with .root files and explore different event generators as well as…