Invariant Mass (GeV/c
- Eun-Joo Kim
- BRAHMS Collaboration), Nucl.Phys
Transverse momentum spectra of Λ and K S particles are presented for Cu+Cu √ sNN = 200 GeV collisions observed at STAR, and compared to Au+Au measurements at the same energy. For both systems, a number of observables are shown to increase at midrapidity (|y | < 0.5) with increasing centrality. These are the integrated Λ and K S yields, the integrated Λ and K S yields per participating nucleon, and mid-pT (1 GeV/c → 4.5 GeV/c) Λ/K S ratios. The RCP ratio is found to be higher for the Λ yields at mid-pT compared to the K S yields for both the Cu+Cu and Au+Au data. In contrast, when similar numbers of participating nucleons are considered for the Cu+Cu and Au+Au data, an indication of increased bulk strangeness production and a higher mid-pT (1 GeV/c → 4.5 GeV/c) Λ/K S ratio are found, for Cu+Cu.