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Title: Pion Freeze-Out Time in Pb + Pb Collisions at 158 AGeV/c Studied via n-/n+ and K-/K+ Ratios

Abstract

The effect of the final state Coulomb interaction on particles produced in Pb+Pb collisions at 158 AGeV/c has been investigated in the WA98 experiment through the study of the {pi}{sup -}/{pi}{sup +} and K{sup -}/K{sup +} ratios measured as a function of m{sub T}-m{sub 0}. While the ratio for kaons shows no significant mT dependence, the {pi}{sup -}/{pi}{sup +} ratio is enhanced at small m{sub T}-m{sub 0} values with an enhancement that increases with centrality. A silicon pad detector located near the target is used to estimate the contribution of hyperon decays to the {pi}{sup -}/{pi}{sup +} ratio. The comparison of results with predictions of the RQMD model in which the Coulomb interaction has been incorporated allows to place constraints on the time of the pion freeze-out.

Authors:
 [1];  [1];  [1]; ORCiD logo [1];  [2]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). et al.
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE
Contributing Org.:
WA98 Collaboration
OSTI Identifier:
931365
DOE Contract Number:  
AC05-00OR22725
Resource Type:
Journal Article
Journal Name:
European Physical Journal. C, Particles and Fields
Additional Journal Information:
Journal Volume: 48; Journal Issue: 2; Journal ID: ISSN 1434-6044
Publisher:
Springer
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 74 ATOMIC AND MOLECULAR PHYSICS; HYPERONS; KAONS; PIONS; SILICON; TARGETS; ATOM-ATOM COLLISIONS; LEAD

Citation Formats

Awes, Terry C., Plasil, F., Silvermyr, David O., Stankus, Paul W., and Young, Glenn R. Pion Freeze-Out Time in Pb + Pb Collisions at 158 AGeV/c Studied via n-/n+ and K-/K+ Ratios. United States: N. p., 2006. Web. doi:10.1140/epjc/s10052-006-0081-x.
Awes, Terry C., Plasil, F., Silvermyr, David O., Stankus, Paul W., & Young, Glenn R. Pion Freeze-Out Time in Pb + Pb Collisions at 158 AGeV/c Studied via n-/n+ and K-/K+ Ratios. United States. doi:10.1140/epjc/s10052-006-0081-x.
Awes, Terry C., Plasil, F., Silvermyr, David O., Stankus, Paul W., and Young, Glenn R. Tue . "Pion Freeze-Out Time in Pb + Pb Collisions at 158 AGeV/c Studied via n-/n+ and K-/K+ Ratios". United States. doi:10.1140/epjc/s10052-006-0081-x.
@article{osti_931365,
title = {Pion Freeze-Out Time in Pb + Pb Collisions at 158 AGeV/c Studied via n-/n+ and K-/K+ Ratios},
author = {Awes, Terry C. and Plasil, F. and Silvermyr, David O. and Stankus, Paul W. and Young, Glenn R.},
abstractNote = {The effect of the final state Coulomb interaction on particles produced in Pb+Pb collisions at 158 AGeV/c has been investigated in the WA98 experiment through the study of the {pi}{sup -}/{pi}{sup +} and K{sup -}/K{sup +} ratios measured as a function of m{sub T}-m{sub 0}. While the ratio for kaons shows no significant mT dependence, the {pi}{sup -}/{pi}{sup +} ratio is enhanced at small m{sub T}-m{sub 0} values with an enhancement that increases with centrality. A silicon pad detector located near the target is used to estimate the contribution of hyperon decays to the {pi}{sup -}/{pi}{sup +} ratio. The comparison of results with predictions of the RQMD model in which the Coulomb interaction has been incorporated allows to place constraints on the time of the pion freeze-out.},
doi = {10.1140/epjc/s10052-006-0081-x},
journal = {European Physical Journal. C, Particles and Fields},
issn = {1434-6044},
number = 2,
volume = 48,
place = {United States},
year = {2006},
month = {11}
}

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