Speaker
Miroslav Simko
(Nuclear Physics Institute of the CAS (CZ))
Description
Baryon/meson ratios (p/$\pi$, $\Lambda$/K$^0_\mathrm{s}$) are observed to be significantly enhanced in central
heavy-ion collisions compared with peripheral heavy-ion collisions and p+p collisions at
RHIC and LHC. Several model calculations
suggest that coalescence hadronization between charm quarks and light quarks will also
lead to an enhancement in the $\Lambda_\mathrm{c}$/D$^0$ ratio. Therefore, it is of great
interest to study the $\Lambda_\mathrm{c}$ baryon production to further understand the hadronization
scheme in the charm sector and constrain total charm yield in heavy-ion collisions. The
possible $\Lambda_\mathrm{c}$/D$^0$ enhancement in heavy-ion collisions will introduce additional
suppression for charm decay electrons due to smaller semi-leptonic decay branching
ratios of $\Lambda_\mathrm{c}$, which could lead to a different interpretation of the heavy flavor decay
electron results.
$\Lambda_\mathrm{c}$ baryons have an extremely small lifetime ($c \tau \sim 60$ $\mu$m) and have not been measured
in heavy-ion collisions yet. The newly installed STAR Heavy Flavor Tracker (HFT) has
shown high efficiency and a superior pointing resolution that facilitate the reconstruction of hadronic decays in
heavy-ion collisions. In 2014 run, STAR has collected 1.2 B events of minimum bias
Au+Au collisions $\sqrt{s_\mathrm{NN}}$ = 200 GeV.
In this poster, we will discuss the feasibility of $\Lambda_\mathrm{c}$ measurement with the HFT in Au+Au
collisions. We will report reconstruction of $\Lambda_\mathrm{c}$ baryons via hadronic decays, including decay channels through
the involvement of various intermediate resonance states using 2014 Au+Au data at
$\sqrt{s_\mathrm{NN}}$ = 200 GeV. In addition, we will discuss the improvement on $\Lambda_\mathrm{c}$ reconstruction
using the HFT with reduced material that is taking data in 2015 (p+p, p+A) and is planned
for future 2016 (Au+Au) collisions.
| On behalf of collaboration: | STAR |
|---|
Primary author
Miroslav Simko
(Nuclear Physics Institute of the CAS (CZ))
