Postdoctoral Researcher in Heavy-Ion Physics (M/F)

id="offer-description" class="ecl-u-type-heading-2 ecl-u-mt-none ecl-u-mb-l">Offer Description The ANR BEAUT project, which is led by LPSC in cooperation with IPHC in Strasbourg and IP2I in Lyon, deals with one of the most basic open questions in quantum chromodynamics (QCD), namely what the transport properties of deconfined matter are. Its objective is to determine, for the first time, from the Run 3 Pb–Pb collisions recorded by the ALICE experiment at the LHC (√(s_NN ) = 5.36 TeV), the spatial diffusion coefficient of heavy quarks, D_s (T), in the quark-gluon plasma (QGP). The beauty quark is particularly useful as a probe in this case since its relaxation time is longer than the lifetime of the fireball and therefore the final momentum distribution of the beauty quark keeps a direct reflection of D_s (T), without being contaminated by partial thermalisation or hadronic rescattering effects. The successful candidate will work on the « beauty jets » aspect of the project, since this is the responsibility of LPSC. As a member of the LPSC ALICE group and under the scientific guidance of the project coordinator, they will have the following duties: (i) develop a machine-learning-based algorithm for identifying jets that arise from beauty quarks (b-tagging), with it being optimised for the high-multiplicity conditions found in Pb–Pb collisions; (ii) measure the nuclear modification factor R_AA and the azimuthal anisotropy v_2 of b-jets, along with their substructure, in order t