Ratios of heavy baryons to heavy mesons in relativistic nucleus-nucleus collisions

Journal Article · Wed Apr 15 00:00:00 EDT 2009 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.79.044905· OSTI ID:21289874

Oh, Yongseok; Ko, Che Ming ^[1]; Lee, Su Houng ^[2]; Yasui, Shigehiro ^[3]

---

1. Cyclotron Institute and Physics Department, Texas A and M University, College Station, Texas 77843 (United States)
2. Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749 (Korea, Republic of)
3. High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 302-0801 (Japan)

Heavy baryon/meson ratios {lambda}{sub c}/D{sup 0} and {lambda}{sub b}/B{sup 0} in relativistic heavy ion collisions are studied in the quark coalescence model. For heavy baryons, we include production from coalescence of heavy quarks with free light quarks as well as with bounded light diquarks that might exist in the strongly coupled quark-gluon plasma produced in these collisions. Including the contribution from decays of heavy hadron resonances and also that due to fragmentation of heavy quarks that are left in the system after coalescence, the resulting {lambda}{sub c}/D{sup 0} and {lambda}{sub b}/B{sup 0} ratios in midrapidity (|y|{<=}0.5) from central Au+Au collisions at {radical}(s{sub NN})=200 GeV are about a factor of five and ten, respectively, larger than those given by the thermal model, and about a factor of ten and twelve, respectively, larger than corresponding ratios in the PYTHIA model for pp collisions. These ratios are reduced by a factor of about 1.6 if there are no diquarks in the quark-gluon plasma. The transverse momentum dependence of the heavy baryon/meson ratios is found to be sensitive to the heavy quark mass, with the {lambda}{sub b}/B{sup 0} ratio being much flatter than the {lambda}{sub c}/D{sup 0} ratio. The latter peaks at the transverse momentum p{sub T}{approx_equal}0.8 GeV but the peak shifts to p{sub T}{approx_equal}2 GeV in the absence of diquarks.

• OSTI ID: 21289874
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 4 Vol. 79; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ATOM-ATOM COLLISIONS
B NEUTRAL MESONS
BARYONS
COALESCENCE
D NEUTRAL MESONS
FRAGMENTATION
GEV RANGE 100-1000
GOLD
HADRON REACTIONS
HEAVY ION REACTIONS
MASS
NUCLEI
PROTON-PROTON INTERACTIONS
QUARK MATTER
QUARK-GLUON INTERACTIONS
QUARKS
RELATIVISTIC RANGE
RESONANCE
SIMULATION
TRANSVERSE MOMENTUM