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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. $Lambda_{c}$ is the lightest charmed baryon with mass close to that of $D^0$ meson, and has an extremely short life time (c$tau$$sim$60 $mu$m). Different models predict different magnitudes of enhancement in the $Lambda_{c}$/$D^0$ ratio depending on the degree to which charm quarks are thermalized in the medium and how the coalescence mechanism is implemented. In these proceedings, we report the first measurement of $Lambda_{c}$ production in heavy-ion collisions using the Heavy Flavor Tracker at STAR. The invariant yield of $Lambda_{c}$ for 3 $<$ $p_T$ $<$ 6 GeV/$c$ is measured in 10-60% central Au+Au collisions at $sqrt{s_{NN}}$ = 200 GeV. The $Lambda_{c}$/$D^0$ ratio is compared to different model calculations, and the physics implications are discussed.
We present measurements of $e^+e^-$ production at midrapidity in Au$+$Au collisions at $sqrt{s_{_{NN}}}$ = 200 GeV. The invariant yield is studied within the PHENIX detector acceptance over a wide range of mass ($m_{ee} <$ 5 GeV/$c^2$) and pair trans
We have measured the distributions of protons and deuterons produced in high energy heavy ion Au+Au collisions at RHIC over a very wide range of transverse and longitudinal momentum. Near mid-rapidity we have also measured the distribution of anti-pr
We report preliminary results of hypertriton observation in heavy-ion collisions at RHIC. We have identified 157 +- 30 candidates in the current sample containing ~10^8 Au+Au events at sqrt{s_{NN}} = 200 GeV. The production rate of hypertriton is clo
The PHENIX experiment has measured $phi$ meson production in $d$$+$Au collisions at $sqrt{s_{_{NN}}}=200$ GeV using the dimuon and dielectron decay channels. The $phi$ meson is measured in the forward (backward) $d$-going (Au-going) direction, $1.2<y
We report on measurements of dielectron ($e^+e^-$) production in Au$+$Au collisions at a center-of-mass energy of 200 GeV per nucleon-nucleon pair using the STAR detector at RHIC. Systematic measurements of the dielectron yield as a function of trans