General information
Organisation
The French Alternative Energies and Atomic Energy Commission (CEA) is a key player in research, development and innovation in four main areas :
• defence and security,
• nuclear energy (fission and fusion),
• technological research for industry,
• fundamental research in the physical sciences and life sciences.
Drawing on its widely acknowledged expertise, and thanks to its 16000 technicians, engineers, researchers and staff, the CEA actively participates in collaborative projects with a large number of academic and industrial partners.
The CEA is established in ten centers spread throughout France
Reference
SL-DRF-26-0534
Direction
DRF
Thesis topic details
Category
Corpuscular physics and outer space
Thesis topics
Elliptic Flow of Charmed Hadrons in Heavy-Ion Collisions at LHCb?
Contract
Thèse
Job description
The FLOALESCENCE project explores one of the most fundamental questions in Quantum Chromodynamics (QCD): how quarks and gluons transition from a deconfined Quark–Gluon Plasma (QGP) into ordinary hadrons.?This transition, called hadronization, occurred microseconds after the Big Bang and can be recreated today in ultra-relativistic lead–lead collisions at CERN’s Large Hadron Collider (LHC).
The PhD will focus on charm quarks—excellent probes of the QGP because they are produced early in the collision and interact throughout its evolution. Using the LHCb detector, uniquely sensitive in the forward rapidity region, the project aims to measure the elliptic flow (v2) of charmed baryons (?c+) and mesons (D0) in Pb–Pb collisions.?The goal is to test whether these heavy quarks thermalize and hadronize through a coalescence mechanism, a key feature of QGP dynamics.
Objectives and tasks:
- Extract and analyze ?c+ and D0 signals in newly collected 2024–2025 Pb–Pb datasets at LHCb.
- Implement a novel flow analysis method (based on the reformulated Lee–Yang Zeros approach) for the first time at LHCb.
- Develop an event-by-event multiplicity metric to correlate flow with system energy density.
- Compare results to theoretical models and cross-check with measurements at central rapidity (ALICE).
- Publish results and present findings at international conferences.
The successful candidate will:
- Develop advanced data-analysis expertise with CERN’s LHCb software framework, ROOT, and machine learning–based signal extraction.
- Gain in-depth knowledge of QCD and relativistic heavy-ion physics, especially QGP properties and collective phenomena.
- Learn modern statistical methods for flow analysis and uncertainty estimation.
- Acquire collaborative and communication skills within a major international experiment (LHCb), including presentations in collaboration meetings and conferences.
- Build strong experience in scientific computing, big-data handling, and detector physics, valuable for both academic and industry careers.
University / doctoral school
PHENIICS (PHENIICS)
Paris-Saclay
Thesis topic location
Site
Saclay
Requester
Position start date
01/10/2026
Person to be contacted by the applicant
Audurier Benjamin
benjamin.audurier@cern.ch
CEA
DRF/IRFU/DPhN/LQGP
CEA Saclay
Irfu/DPhN
Bât. 703
91191 Gif-sur-Yvette CEDEX
Tutor / Responsible thesis director
OLLITRAULT Jean-Yves
Jean-Yves.Ollitrault@cea.fr
CNRS-URA 2306
DSM - Institut de Physique Théorique
Institut de Physique Théorique - CEA Saclay
01 6908 7269
En savoir plus
https://irfu.cea.fr/Phocea/Vie_des_labos/Ast/ast_groupe.php?id_groupe=500