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Title: Strangelet search in AuAu collisions at {radical}{ovr s}{sub NN} = GeV.

Abstract

We have searched for strangelets in a triggered sample of 61 million central (top 4%) Au+Au collisions at {radical}s{sub NN} = 200 GeV near beam rapidities at the STAR solenoidal tracker detector at the BNL Relativistic Heavy Ion Collider. We have sensitivity to metastable strangelets with lifetimes of order = {ge} 0.1 ns, in contrast to limits over ten times longer in BNL Alternating Gradient Synchrotron (AGS) studies and longer still at the CERN Super Proton Synchrotron (SPS). Upper limits of a few 10{sup -6} to 10{sup -7} per central Au+Au collision are set for strangelets with mass {approx}> 30 GeV/c{sup 2}.

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC); National Science Foundation (NSF); Swiss NSF
OSTI Identifier:
966035
Report Number(s):
ANL-HEP-PR-09-65
Journal ID: ISSN 0556-2813; PRVCAN; TRN: US0904023
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Phys. Lett.; Journal Volume: 76; Journal Issue: 76 ; 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
43 PARTICLE ACCELERATORS; BNL; CERN; HEAVY IONS; PROTONS; SENSITIVITY; SYNCHROTRONS

Citation Formats

Cadman, R. V., Spinka, H. M., Krueger, K., McClain, C. J., Underwood, D. G., Abelev, B. I., Aggarwal, M. M., Ahammed, Z., Anderson, B. D., Arkhipkin, D., High Energy Physics, Univ.of Illinois, Panjab Univ., Varbialbe Energy Cyclotron Centre, Kent State Univ., and Particle Physics Lab.. Strangelet search in AuAu collisions at {radical}{ovr s}{sub NN} = GeV.. United States: N. p., 2007. Web. doi:10.1103/PhysRevC.74.064906.
Cadman, R. V., Spinka, H. M., Krueger, K., McClain, C. J., Underwood, D. G., Abelev, B. I., Aggarwal, M. M., Ahammed, Z., Anderson, B. D., Arkhipkin, D., High Energy Physics, Univ.of Illinois, Panjab Univ., Varbialbe Energy Cyclotron Centre, Kent State Univ., & Particle Physics Lab.. Strangelet search in AuAu collisions at {radical}{ovr s}{sub NN} = GeV.. United States. doi:10.1103/PhysRevC.74.064906.
Cadman, R. V., Spinka, H. M., Krueger, K., McClain, C. J., Underwood, D. G., Abelev, B. I., Aggarwal, M. M., Ahammed, Z., Anderson, B. D., Arkhipkin, D., High Energy Physics, Univ.of Illinois, Panjab Univ., Varbialbe Energy Cyclotron Centre, Kent State Univ., and Particle Physics Lab.. Mon . "Strangelet search in AuAu collisions at {radical}{ovr s}{sub NN} = GeV.". United States. doi:10.1103/PhysRevC.74.064906.
@article{osti_966035,
title = {Strangelet search in AuAu collisions at {radical}{ovr s}{sub NN} = GeV.},
author = {Cadman, R. V. and Spinka, H. M. and Krueger, K. and McClain, C. J. and Underwood, D. G. and Abelev, B. I. and Aggarwal, M. M. and Ahammed, Z. and Anderson, B. D. and Arkhipkin, D. and High Energy Physics and Univ.of Illinois and Panjab Univ. and Varbialbe Energy Cyclotron Centre and Kent State Univ. and Particle Physics Lab.},
abstractNote = {We have searched for strangelets in a triggered sample of 61 million central (top 4%) Au+Au collisions at {radical}s{sub NN} = 200 GeV near beam rapidities at the STAR solenoidal tracker detector at the BNL Relativistic Heavy Ion Collider. We have sensitivity to metastable strangelets with lifetimes of order = {ge} 0.1 ns, in contrast to limits over ten times longer in BNL Alternating Gradient Synchrotron (AGS) studies and longer still at the CERN Super Proton Synchrotron (SPS). Upper limits of a few 10{sup -6} to 10{sup -7} per central Au+Au collision are set for strangelets with mass {approx}> 30 GeV/c{sup 2}.},
doi = {10.1103/PhysRevC.74.064906},
journal = {Phys. Lett.},
number = 76 ; 2007,
volume = 76,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • We present first measurements of the pseudorapidity and azimuth ({eta}, {phi}) bin-size dependence of event-wise mean transverse-momentum <p{sub T}> fluctuations for Au-Au collisions at {radical}s{sub NN} = 200 GeV. We invert that dependence to obtain p{sub t} autocorrelations on differences ({eta}{sub {Delta}}, {phi}{sub {Delta}}) interpreted to represent velocity/temperature distributions on ({eta}, {phi}). The general form of the autocorrelations suggests that the basic correlation mechanism is parton fragmentation. The autocorrelations vary rapidly with collision centrality, which suggests that fragmentation is strongly modified by a dissipative medium in the more central Au-Au collisions relative to peripheral or p-p collisions.
  • Azimuthal correlations for large transverse momentum charged hadrons have been measured over a wide pseudorapidity range and full azimuth in Au+Au and p+p collisions at {radical}{ovr S{sub NN}}=200 GeV. The small-angle correlations observed in p+p collisions and at all centralities of Au+Au collisions are characteristic of hard-scattering processes previously observed in high-energy collisions. A strong back-to-back correlation exists for p+p and peripheral Au+Au. In contrast, the back-to-back correlations are reduced considerably in the most central Au+Au collisions, indicating substantial interaction as the hard-scattered partons or their fragmentation products traverse the medium.
  • The STAR collaboration at the BNL Relativistic Heavy-Ion Collider (RHIC) reports measurements of the inclusive yield of nonphotonic electrons, which arise dominantly from semileptonic decays of heavy flavor mesons, over a broad range of transverse momenta (1.2 < p{sub T} < 10 GeV/c) in p+p, d+Au, and Au+Au collisions at {radical}s{sub NN} = 200 GeV. The nonphotonic electron yield exhibits an unexpectedly large suppression in central Au+Au collisions at high p{sub T}, suggesting substantial heavy-quark energy loss at RHIC. The centrality and p{sub T} dependences of the suppression provide constraints on theoretical models of suppression.
  • We study the energy dependence of the transverse momentum (p{sub T}) spectra for charged pions, protons and anti-protons for Au+Au collisions at {radical}s{sub NN} = 62.4 and 200 GeV. Data are presented at mid-rapidity (|y| < 0.5) for 0.2 < p{sub T} < 12 GeV/c. In the intermediate p{sub T} region (2 < p{sub T} < 6 GeV/c), the nuclear modification factor is higher at 62.4 GeV than at 200 GeV, while at higher p{sub T} (p{sub T} > 7 GeV/c) the modification is similar for both energies. The p/{pi}{sup +} and {bar p}/{pi}{sup -} ratios for central collisions atmore » {radical}s{sub NN} = 62.4 GeV peak at p{sub T} {approx_equal} 2 GeV/c. In the p{sub T} range where recombination is expected to dominate, the p/{pi}{sup +} ratios at 62.4 GeV are larger than at 200 GeV, while the {bar p}/{pi}{sup -} ratios are smaller. For p{sub T} > 2 GeV/c, the {bar p}/{pi}{sup -} ratios at the two beam energies are independent of p{sub T} and centrality indicating that the dependence of the {bar p}/{pi}{sup -} ratio on p{sub T} does not change between 62.4 and 200 GeV. These findings challenge various models incorporating jet quenching and/or constituent quark coalescence.« less
  • No abstract prepared.