اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدFirst measurement of $Lambda_c$ baryon production in Au+Au collisions at $sqrt{s_{rm NN}}$ = 200 GeV
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We report on the first measurement of the charmed baryon $Lambda_c^{pm}$ production at midrapidity ($|y|$ $<$ 1) in Au+Au collisions at $sqrt{s_{NN}}$ = 200 GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider. The $Lambda_c$/$D^0$ (denoting ($Lambda_c^++Lambda_c^-$)/($D^0+bar{D^0}$)) yield ratio is measured to be 1.08 $pm$ 0.16 (stat.) $pm$ 0.26 (sys.) in the 0--20% most central Au+Au collisions for the transverse momentum ($p_T$) range 3 $<$ $p_T$ $<$ 6 GeV/$c$. This is significantly larger than the PYTHIA model calculations for $p+p$ collisions. The measured $Lambda_c$/$D^0$ ratio, as a function of $p_T$ and collision centrality, is comparable to the baryon-to-meson ratios for light and strange hadrons in Au+Au collisions. Model calculations including coalescence hadronization for charmed baryon and meson formation reproduce the features of our measured $Lambda_c$/$D^0$ ratio.
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