Lambda flow and Lambda-P correlation in Au plus Au collisions at AGS energies

Citation
P. Chung et al., Lambda flow and Lambda-P correlation in Au plus Au collisions at AGS energies, J PHYS G-NU, 27(3), 2001, pp. 293-299
Citations number
15
Categorie Soggetti
Physics
Journal title
JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS
ISSN journal
09543899 → ACNP
Volume
27
Issue
3
Year of publication
2001
Pages
293 - 299
Database
ISI
SICI code
0954-3899(200103)27:3<293:LFALCI>2.0.ZU;2-Y
Abstract
Transverse and radial how measurements are presented for A hyperons along w ith A-P correlations from Au + Au collisions at AGS energies. The flow meas urements are compared with those of co-produced protons. The measurements i ndicate that A hyperons flow consistently in the same direction as protons but with a smaller magnitude for all beam energies. Comparisons with RQMD c alculations show that the experimentally determined Lambda sideward flow is consistently larger compared with the calculated value obtained from scatt ering processes only. The experimental transverse flow ratio Lambda /P is c onsistent with predictions (similar or equal to (2)/(3)) of the quark count ing rule at 2 A GeV but is found to decrease with increasing beam energy. T hese observations may be related to the detailed features of the A-nucleon potential for the nuclear densities produced. At 6 A GeV, np correlation fu nctions are observed to be essentially flat (within statistical uncertainty ), indicating little or no correlation between As and co-produced protons. This suggests that As may have a spacetime emission pattern which is differ ent from that for protons. Further evidence from radial flow measurements a lso indicates that 6 A GeV A hyperons (at mid-rapidity) do not share the sa me emitting source characteristics as coproduced protons.