Study of Heavy Flavor at the STAR Experiment

0557370 - ÚJF 2023 RIV CZ eng D - Thesis
Šimko, Miroslav
Study of Heavy Flavor at the STAR Experiment.
Ústav jaderné fyziky AV ČR. Defended: Fakulta jaderná a fyzikálně inženýrská, Katedra fyziky, ČVUT. 31. 3. 2021. - Praha, 2021. 170 s.
Research Infrastructure: BNL-CZ II - 90109
Institutional support: RVO:61389005
Keywords : Lambda c * coalescence * STAR * RHIC * HFT
OECD category: Particles and field physics
https://www.fjfi.cvut.cz/cz/studium/doktorske-studium/archiv-doktorskych-praci/967-simko-miroslav

This work focuses on the analysis of Lambda c which is the lightest baryon containing a charm quark. As such, the Lambda c presents a unique probe to study the behavior of charm quarks in the hot and dense QCD medium created in ultra-relativistic heavy-ion collisions. Together with the measurement of the D0 meson, we can study modes of charm quark hadronization and bring additional insights into the quark coalescense process in the strongly coupled quark-gluon plasma. Λc baryons have an extremely short lifetime which makes the reconstruction experimentally challenging. The novel detector Heavy Flavor Tracker, installed at the STAR experiment between the years 2014-2016, has shown high efficiency and an unparalleled pointing resolution that can facilitate the Lambda c reconstruction in heavy-ion collisions. In this thesis, we describe the first reconstruction of the Lambda c baryons via hadronic decays in Au+Au collisions and, moreover, the first such measurement differentiated in transverse momentum and the number of participants in heavy-ion collisions. The measured yield shows that the Λc make a sizeable contribution to the total charm yield in Au+Au collisions. Moreover, the Labmda c/D0 yield ratio is significantly larger in Au+Au collisions, compared to simulated p+p collisions, and is consistent with theoretical calculations that include charm-quark coalescence.
Permanent Link: http://hdl.handle.net/11104/0331412