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arXiv · 1704.04353

$Λ_{c}$ Production in Au+Au Collisions at $\sqrt{s_{NN}}$ = 200 GeV measured by the STAR experiment

Abstract

At RHIC, enhancements in the baryon-to-meson ratio for light hadrons and hadrons containing strange quarks have been observed in central heavy-ion collisions compared to those in p+p and peripheral heavy-ion collisions in the intermediate transverse momentum ($p_T$) range (2 $<$ $p_T$ $<$ 6 GeV/$c$). This can be explained by the hadronization mechanism involving multi-parton coalescence. $Λ_{c}$ is the lightest charmed baryon with mass close to that of $D^0$ meson, and has an extremely short life time (c$τ$$\sim$60 $μ$m). Different models predict different magnitudes of enhancement in the $Λ_{c}$/$D^0$ ratio depending on the degree to which charm quarks are thermalized in the medium and how the coalescence mechanism is implemented. In these proceedings, we report the first measurement of $Λ_{c}$ production in heavy-ion collisions using the Heavy Flavor Tracker at STAR. The invariant yield of $Λ_{c}$ for 3 $<$ $p_T$ $<$ 6 GeV/$c$ is measured in 10-60% central Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. The $Λ_{c}$/$D^0$ ratio is compared to different model calculations, and the physics implications are discussed.

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BibTeXRIS

Guannan Xie. 2017-04-14. $Λ_{c}$ Production in Au+Au Collisions at $\sqrt{s_{NN}}$ = 200 GeV measured by the STAR experiment. https://doi.org/10.1016/j.nuclphysa.2017.06.004

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