The Irène Joliot-Curie Physics Laboratory of 2 Infinities (IJCLab) is a UMR under the supervision of the CNRS (IN2P3), the University of Paris-Saclay and the University of Paris is located on the campus of the University of Paris -Saclay in Orsay. The laboratory is located on the campus of the Université Paris-Sud, Université Paris-Saclay in Orsay. The campus is located 20 km south of Paris and easily accessible by RER in 35 minutes.
IJCLab was born in 2020 from the merger of five units (CSNSM, IMNC, IPN, LAL, LPT). The staff is made up of nearly 560 permanent (340 engineers, technicians and administrators and 220 researchers and teacher-researchers) and approximately 200 non-permanent including 120 doctoral students. The research themes of the laboratory are nuclear physics, high energy physics, theoretical physics, astroparticles, astrophysics and cosmology, particle accelerators, energy and the environment and health. IJCLab has very significant technical capacities (around 280 IT) in all the major fields required to design, develop / implement the experimental devices necessary for its scientific activity, as well as the design, development and use of instruments. IJCLab is associated with the doctoral school PHENIICS (ED N° 576) of Ile-de-France. The topics of PHENIICS are centered around the themes of subatomic physics. PHENIICS spans the fundamental to applied sciences, and is rooted in the unique network of world-renowed research institutes on these themes situated in the University of Paris-Saclay.
The PhD student will work in the ILC group which is a member of the department of high-energy and hadronic physics of the laboratory. The group is involved in hardware and software studies for highly granular calorimeters and physics studies or future e+e- colliders. It consists of three senior physicists and one postdoc. The project will be supported by Machine Learning experts of the ATLAS Group of IJClab and of the IJCLab's computing department. We have full access to the engineering and computing facilities of IJCLab as well as to computing facilities of CNRS/IN2P3 and the University Paris Saclay.
IJCLAB bases its recruitment policy on the promotion of equality, diversity and inclusion. These essential values allow the professional development of agents, who are real actors iforcollective success, but also for the development of the laboratory itself.

The precise reconstruction of all products of a particle interaction is of critical importance for the discovery reach and the potential for precision measurements of fundamental aspects of the properties and interactions of elementary particles. The detectors at future particle colliders use highly granular “imaging calorimeters” to provide detailed three-dimensional spatial information of the energy deposited by the passage and the showering of particle in the detector. The PhD student will exploit this information with sophisticated particle flow algorithms, which optimally combine the information available from the different subsystems of the detector. The capability of the calorimeters to detect, separate and measure individual final-state particles is critical. Modern timing devices that achieve precisions of a few 10 to 100 ps turn imaging calorimeters into five-dimensional detectors, covering space, energy and time. The thesis will captilise on these new technologies and the PhD Student will extend existing particle flow algorithms beyond the state of the art, both classically and by integrating machine learning techniques to enable the full exploitation of the added complexity. In order to inform the requirements for timing elements in calorimeter systems at future e+e–- colliders (Higgs Factories), the PhD Thesis includes the study of key physics channels in the area of Higgs physics and electroweak precision measurements The understanding of the required timing precision in calorimeter systems will guid future R&D directions in this area.