4 research outputs found
Statistical Origin of Constituent-Quark Scaling in the QGP hadronization
Nonextensive statistics in a Blast-Wave model (TBW) is implemented to
describe the identified hadron production in relativistic p+p and
nucleus-nucleus collisions. Incorporating the core and corona components within
the TBW formalism allows us to describe simultaneously some of the major
observations in hadronic observables at the Relativistic Heavy-Ion Collider
(RHIC): the Number of Constituent Quark Scaling (NCQ), the large radial and
elliptic flow, the effect of gluon saturation and the suppression of hadron
production at high transverse momentum (pT) due to jet quenching. In this
formalism, the NCQ scaling at RHIC appears as a consequence of non-equilibrium
process. Our study also provides concise reference distributions with a least
chi2 fit of the available experimental data for future experiments and models.Comment: 4 pages, 3 figures; added two tables, explained a little bit more on
TBW_p
Improving the dE/dx calibration of the STAR TPC for the high-pT hadron identification
We derive a method to improve particle identification (PID) at high
transverse momentum () using the relativistic rise of the ionization
energy loss () when charged particles traverse the Time Projection
Chamber (TPC) at STAR. Electrons triggered and identified by the Barrel
Electro-Magnetic Calorimeter (BEMC), pure protons and pions from (), and
decays are used to obtain the value and
its width at given . We found that the deviation of the
from the Bichsel function can be up to () in p+p
collisions at GeV taken and subsequently calibrated in year
2005. The deviation is approximately a function of independent of
particle species and can be described with a function of . The deviations obtained with this method are used to
re-calibrate the data sample from p+p collision for physics analysis of
identified hadron spectra and their correlations up to transverse momentum of
15 GeV/. The ratio of (dominantly from -conversion) is
also used to correct the residual asymmetry in the negative and positive
charged hadrons due to momentun distortion in the STAR TPC.Comment: 18pages, 10 figure