Can STAR $p+p$ data help constrain fragmentation functions for strange hadrons
Abstract
STAR has measured a variety of strange particle species in collisions at =200 GeV. These high statistics data are ideal for comparing to existing leading- and next-to-leading order perturbative QCD (pQCD) models. Leading-order (LO) models such as PYTHIA need to be tuned to describe identified strange particle data from STAR. We show that tuned PYTHIA can also describe the pt-spectra of strange resonances. More rigorous Next-to-Leading order pQCD calculations using parameterized fragmentation functions for quarks and gluons will also be compared to STAR data. The OPAL experiment has recently released data from light quark flavor tagged analyses allowing for the first time to make precise parameterizations of light flavor separated fragmentation function. We show that our Lambda data put a more stringent constraint on the gluon fragmentation function than data. Furthermore we show that pQCD fails to describe the observed enhancement of baryon-to-meson ratio at intermediate pt (2-6 GeV/c), which may be a first indication of other, non-perturbative mechanisms at play in collisions at that momentum.
Cite
@article{arxiv.hep-ex/0606020,
title = {Can STAR $p+p$ data help constrain fragmentation functions for strange hadrons},
author = {Mark Heinz},
journal= {arXiv preprint arXiv:hep-ex/0606020},
year = {2007}
}
Comments
8 pages, Conference Proceedings for 22nd Winter Workshop on Nuclear Dynamics, San Diego CA, March 11-19, 2006