1999/09/17 by the EXO Collaboration, Z. Xu, The E864 Collaboration +2
Physics and Astronomy · #FOS: Physical sciences #High-Energy Particle Collisions Research #Nuclear Experiment (nucl-ex) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #nucl-ex
paper · pdf · doi:10.48550/arxiv.nucl-ex/9909012
6 pages,3 figures. Talk at ISMD99
arxiv created 1999/09/17 · openalex publication_date 1999/09/17 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Light nuclei can be produced in the central reaction zone via coalescence in relativistic heavy ion collisions. E864 at BNL has measured the production of ten stable light nuclei with nuclear number of A=1 to A=7 at rapidity y≃1.9 and pT/A≤300MeV/c. Data were taken with a Au beam of momentum of 11.5 A GeV/c on a Pb or Pt target with different experimental settings. The invariant yields show a striking exponential dependence on nuclear number over ten orders of magnitudes with a penalty factor of about 50 per additional nucleon. This penalty factor is used to estimate the strange quark matter (strangelet) production in the baryon rich and strangeness enhanced environment. The measurements of the production of antiproton, antideuteron, hypernuclei (3ΛH,4ΛH), and strongly unstable nuclear states (4H,5Li, 5Li*, 5He) are presented as well. A model of local thermal equilibrium with radial flow at the kinetic freeze-out with a temperature of T=112±10MeV, chemical potential of μB=503±20MeV and flow velocity of about √V⊥2≃0.5c seems to be able to describe the data in the gross scale with the exceptions of the production of antihyperons and hypernuclei. The large antihyperon production and the extra penalty for hypernuclei production are quite surprising.