Abstract: Strange particle production at RHIC...
Measurements of strangeness production in heavy-ion collisions were originally conceived to be the smoking gun of
QGP formation . It was argued that due to a drop in the strange quark's dynamical
mass, strangeness in the QGP would equilibrate on small time scales relative to a hadronic gas.
In heavy-ion collisions, comparing final state strangeness yields per participant to thermal model predictions from the
canonical formulation , provide a test for strangeness equilibration in the partonic stage. These predictions have
qualitatively reproduced various aspects of the data from Au+Au 200 GeV collisions at RHIC, however, as
with SPS energies, a complete theoretical description has yet to be achieved .
We present mid-rapidity strange particle yields from Cu+Cu 200 GeV collisions which show collisional geometry plays
a crucial role for strangeness production. Counter to predictions from the canonical formulation, all particles exhibit
higher yields compared to Au+Au 200 GeV collisions with a similar number of participants. We compare
various energy density calculations to strangeness yields and find a scaling regime where strangeness yields per
participant for Cu+Cu and Au+Au lie on a common trend. Such a regime may have important
consequences for strangeness production and its role as a QGP signature.
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