作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Hollis, R. S.; Garcia-Solis, E. J.; Hofman, D. J.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Okada, H.; Longacre, R. S.; Sorensen, P.; Christie, W.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Yip, K.; Didenko, L.; Guryn, W.; Ludlam, T.; Van Buren, G.; Fachini, P.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.; Ng, M. J.; Trattner, A. L.] Univ Calif Berkeley, Berkeley, CA 94720 USA.;[Sanchez, M. Calderon de la Barca; Das, D.; Mall, O. I.; Draper, J. E.; Cebra, D.; Reed, R.; Romero, J. L.; Haag, B.] Univ Calif Davis, Davis, CA 95616 USA.;[Guertin, S. M.; Igo, G.; Kurnadi, P.; Whitten, C., Jr.; Trentalange, S.; Gangadharan, D. R.; Huang, H. Z.; Ghazikhanian, V.; Biritz, B.; Cendejas, R.; Tsai, O. D.; Staszak, D.; Wang, G.] Univ Calif Los Angeles, Los Angeles, CA 90095 USA.
通讯机构:
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
作者:
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Anderson, B. D.;Arkhipkin, D.;...
期刊:
PHYSICAL REVIEW C,2009年79(3) ISSN:2469-9985
通讯作者:
Abelev, B. I.
作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Callner, J.; Hollis, R. S.; Hofman, D. J.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Jones, P. G.; Elhalhuli, E.; Gaillard, L.; Timmins, A. R.; Burton, T. P.; Nelson, J. M.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Lamont, M. A. C.; Ljubicic, T.; Bueltmann, S.; Hallman, T. J.; Buren, G. Van; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Chung, S. U.; Okada, H.; Longacre, R. S.; Lynn, D.; Sorensen, P.; Christie, W.; Zhang, H.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; Love, W. A.; Guryn, W.; Ludlam, T.; Fachini, P.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.; Ng, M. J.; Trattner, A. L.] Univ Calif Berkeley, Berkeley, CA 94720 USA.
通讯机构:
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
摘要:
Identified charged-particle spectra of pi(+/-), K-+/-, p, and (p) over bar at midrapidity (vertical bar y vertical bar < 0.1) measured by the dE/dx method in the STAR (solenoidal tracker at the BNL Relativistic Heavy Ion Collider) time projection chamber are reported for pp and d + Au collisions at root s(NN) = 200 GeV and for Au + Au collisions at 62.4, 130, and 200 GeV. Average transverse momenta, total particle production, particle yield ratios, strangeness, and baryon production rates are investigated as a function of the collision system and centrality. The transverse momentum spectra are found to be flatter for heavy particles than for light particles in all collision systems; the effect is more prominent for more central collisions. The extracted average transverse momentum of each particle species follows a trend determined by the total charged-particle multiplicity density. The Bjorken energy density estimate is at least several GeV/fm(3) for a formation time less than 1 fm/c. A significantly larger net-baryon density and a stronger increase of the net-baryon density with centrality are found in Au + Au collisions at 62.4 GeV than at the two higher energies. Antibaryon production relative to total particle multiplicity is found to be constant over centrality, but increases with the collision energy. Strangeness production relative to total particle multiplicity is similar at the three measured RHIC energies. Relative strangeness production increases quickly with centrality in peripheral Au + Au collisions, to a value about 50% above the pp value, and remains rather constant in more central collisions. Bulk freeze-out properties are extracted from thermal equilibrium model and hydrodynamics-motivated blast-wave model fits to the data. Resonance decays are found to have little effect on the extracted kinetic freeze-out parameters because of the transverse momentum range of our measurements. The extracted chemical freeze-out temperature is constant, independent of collision system or centrality; its value is close to the predicted phase-transition temperature, suggesting that chemical freeze-out happens in the vicinity of hadronization and the chemical freeze-out temperature is universal despite the vastly different initial conditions in the collision systems. The extracted kinetic freeze-out temperature, while similar to the chemical freeze-out temperature in pp, d + Au, and peripheral Au + Au collisions, drops significantly with centrality in Au + Au collisions, whereas the extracted transverse radial flow velocity increases rapidly with centrality. There appears to be a prolonged period of particle elastic scatterings from chemical to kinetic freeze-out in central Au + Au collisions. The bulk properties extracted at chemical and kinetic freeze-out are observed to evolve smoothly over the measured energy range, collision systems, and collision centralities.
作者机构:
[Abelev, B. I.; Barannikova, O.; Hollis, R. S.; Hofman, D. J.; Garcia-Solis, E.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Underwood, D. G.; Krueger, K.; Spinka, H. M.; Bhasin, A.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Jones, P. G.; Elhalhuli, E.; Gaillard, L.; Timmins, A. R.; Burton, T. P.; Nelson, J. M.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Bland, L. C.; Chung, S. U.; Okada, H.; Longacre, R. S.; Lynn, D.; Sorensen, P.; Christie, W.; Zhang, H.; Lebedev, A.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Didenko, L.; Guryn, W.; Ludlam, T.; Van Buren, G.; Fachini, P.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.; Ng, M. J.; Trattner, A. L.] Univ Calif Berkeley, Berkeley, CA 94720 USA.
通讯机构:
[Abelev, B. I.] A;Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA.
作者:
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Anderson, B. D.;Arkhipkin, D.;...
期刊:
PHYSICAL REVIEW D,2009年79(11) ISSN:2470-0010
通讯作者:
Abelev, B. I.
作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Hollis, R. S.; Garcia-Solis, E. J.; Hofman, D. J.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Ullrich, T.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Okada, H.; Longacre, R. S.; Sorensen, P.; Christie, W.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Didenko, L.; Guryn, W.; Ludlam, T.; Van Buren, G.; Fachini, P.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.; Ng, M. J.; Trattner, A. L.] Univ Calif Berkeley, Berkeley, CA 94720 USA.;[Sanchez, M. Calderon de la Barca; Das, D.; Mall, O. I.; Draper, J. E.; Cebra, D.; Reed, R.; Romero, J. L.; Haag, B.] Univ Calif Davis, Davis, CA 95616 USA.;[Guertin, S. M.; Igo, G.; Kurnadi, P.; Whitten, C., Jr.; Trentalange, S.; Gangadharan, D. R.; Huang, H. Z.; Ghazikhanian, V.; Biritz, B.; Cendejas, R.; Tsai, O. D.; Staszak, D.; Wang, G.] Univ Calif Los Angeles, Los Angeles, CA 90095 USA.
通讯机构:
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
作者:
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Alakhverdyants, A. V.;Anderson, B. D.;...
期刊:
PHYSICAL REVIEW C,2009年80(6) ISSN:2469-9985
通讯作者:
Abelev, B. I.
作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Hollis, R. S.; Kauder, K.; Garcia-Solis, E. J.; Hofman, D. J.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Jones, P. G.; Elhalhuli, E.; Gaillard, L.; Burton, T. P.; Nelson, J. M.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Okada, H.; Longacre, R. S.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Yip, K.; Didenko, L.; Guryn, W.; Ludlam, T.; Van Buren, G.; Fachini, P.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Sanchez, M. Calderon de la Barca; Das, D.; Mall, O. I.; Draper, J. E.; Cebra, D.; Reed, R.; Romero, J. L.; Haag, B.; Liu, H.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
摘要:
The STAR Collaboration at the Relativistic Heavy Ion Collider presents a systematic study of high-transverse-momentum charged-di-hadron correlations at small azimuthal pair separation Delta phi in d+Au and central Au+Au collisions at s(NN)=200 GeV. Significant correlated yield for pairs with large longitudinal separation Delta eta is observed in central Au+Au collisions, in contrast to d+Au collisions. The associated yield distribution in Delta eta x Delta phi can be decomposed into a narrow jet-like peak at small angular separation which has a similar shape to that found in d+Au collisions, and a component that is narrow in Delta phi and depends only weakly on Delta eta, the "ridge." Using two systematically independent determinations of the background normalization and shape, finite ridge yield is found to persist for trigger p(t)>6 GeV/c, indicating that it is correlated with jet production. The transverse-momentum spectrum of hadrons comprising the ridge is found to be similar to that of bulk particle production in the measured range (2 < p(t)< 4 GeV/c).
作者:
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Anderson, B. D.;Arkhipkin, D.;...
期刊:
PHYSICAL REVIEW C,2009年80(4) ISSN:2469-9985
通讯作者:
Abelev, B. I.
作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Hollis, R. S.; Garcia-Solis, E. J.; Hofman, D. J.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Jones, P. G.; Elhalhuli, E.; Gaillard, L.; Burton, T. P.; Nelson, J. M.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Okada, H.; Longacre, R. S.; Sorensen, P.; Christie, W.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Yip, K.; Didenko, L.; Guryn, W.; Ludlam, T.; Van Buren, G.; Fachini, P.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.; Ng, M. J.; Trattner, A. L.] Univ Calif Berkeley, Berkeley, CA 94720 USA.
通讯机构:
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
摘要:
The STAR Collaboration at the Relativistic Heavy Ion Collider presents measurements of J/psi e(+) e(-) at midrapidity and high transverse momentum (pT > 5 GeV/c) in p + p and central Cu + Cu collisions at root s(NN) = 200 GeV. The inclusive J/psi production cross section for Cu + Cu collisions is found to be consistent at high p(T) with the binary collision-scaled cross section for p + p collisions. At a confidence level of 97%, this is in contrast to a suppression of J/psi production observed at lower p(T). Azimuthal correlations of J/psi with charged hadrons in p + p collisions provide an estimate of the contribution of B-hadron decays to J/psi production of 13% +/- 5%.
作者机构:
[Jiayun Chen; Feng Liu] Institute of Particle Physics,CCNU,Wuhan,430079,P.R.China;[Jiaxu Zuo] Institute of High Energy Physics,CAS,Beijing 100049,P.R.China;[Aihong Tang] Physics Department,Brookhaven National Lab.,Upton,NY 11973,USA;[Yugang Ma; Xiangzhou Cai] Shanghai Institute of Applied PhysicsCAS,Shanghai 201800,P.R.China
会议名称:
The 10th International Conference on Nucleus-Nucleus Collisions(第十届国际核—核碰撞会议
会议时间:
2009-8-16
会议地点:
北京
会议主办单位:
中国物理学会;中国核学会
会议论文集名称:
The 10th International Conference on Nucleus-Nucleus Collisions(第十届国际核—核碰撞会议论文集
作者机构:
[Liu Feng; Wu Kejun] Institute of Particle Physics,Huazhong Normal University,Wuhan 430079,China;[Liu Feng; Wu Kejun] Key Laboratory of Quark & Lepton Physics (CCNU),Ministy of Education,China
会议名称:
The 10th International Conference on Nucleus-Nucleus Collisions(第十届国际核—核碰撞会议
会议时间:
2009-8-16
会议地点:
北京
会议主办单位:
中国物理学会;中国核学会
会议论文集名称:
The 10th International Conference on Nucleus-Nucleus Collisions(第十届国际核—核碰撞会议论文集
作者:
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Anderson, B. D.;Arkhipkin, D.;...
期刊:
PHYSICAL REVIEW C,2009年79(2) ISSN:2469-9985
通讯作者:
Abelev, B. I.
作者机构:
[Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Jones, P. G.; Elhalhuli, E.; Gaillard, L.; Timmins, A. R.; Burton, T. P.; Nelson, J. M.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Lamont, M. A. C.; LeVine, M. J.; Hallman, T. J.; Buren, G. Van; Xu, Z.; Ogawa, A.; Ruan, L.; Lu, Y.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Rykov, V.; Laue, F.; Bland, L. C.; Chung, S. U.; Okada, H.; Longacre, R. S.; Lynn, D.; Sorensen, P.; Dictel, T.; Christie, W.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Didenko, L.; Guryn, W.; Ludlam, T.; Potekhin, M.; Fachini, P.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Sanchez, M. Calderon de la Barca; Das, D.; Cebra, D.; Ma, Y. G.; Romero, J. L.] Univ Calif Davis, Davis, CA 95616 USA.;[Guertin, S. M.; Igo, G.; Kurnadi, P.; Whitten, C., Jr.; Trentalange, S.; Gangadharan, D. R.; Huang, H. Z.; Ghazikhanian, V.; Biritz, B.; Cendejas, R.; Tsai, O. D.; Staszak, D.; Wang, G.] Univ Calif Los Angeles, Los Angeles, CA 90095 USA.
通讯机构:
[Abelev, B. I.] A;Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA.
作者:
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Anderson, B. D.;Arkhipkin, D.;...
期刊:
PHYSICAL REVIEW C,2009年79(6) ISSN:2469-9985
通讯作者:
Abelev, B. I.
作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Callner, J.; Hollis, R. S.; Hofman, D. J.; Garcia-Solis, E.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Abelev, B. I.; Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Ullrich, T.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Bueltmann, S.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Chung, S. U.; Okada, H.; Longacre, R. S.; Lynn, D.; Sorensen, P.; Christie, W.; Zhang, H.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Didenko, L.; Guryn, W.; Ludlam, T.; Van Buren, G.; Fachini, P.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.; Ng, M. J.; Trattner, A. L.] Univ Calif Berkeley, Berkeley, CA 94720 USA.;[Sanchez, M. Calderon de la Barca; Das, D.; Draper, J. E.; Cebra, D.; Mall, M. I.; Reed, R.; Romero, J. L.; Haag, B.; Liu, H.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Abelev, B. I.] A;Argonne Natl Lab, Argonne, IL 60439 USA.
摘要:
We present results for the measurement of phi meson production via its charged kaon decay channel phi -> K+ K- Au + Au collisions at root S-NN = 62.4, 130, and 200 GeV, and in p + p and d + Au collisions at v root S-NN = 200 GeV from the STAR experiment at the BNL Relativistic Heavy Ion Collider (RHIC). The midrapidity (vertical bar y vertical bar < 0.5) phi meson transverse momentum (p(T)) spectra in central Au + Au collisions are found to be well described by a single exponential distribution. On the other hand, the p(T) spectra from p + p, d + Au, and peripheral Au + Au collisions show power-law tails at intermediate and high p(T) and are described better by Levy distributions. The constant phi/K- yield ratio vs beam species, collision centrality, and colliding energy is in contradiction with expectations from models having kaon coalescence as the dominant mechanism for phi production at RHIC. The Omega/phi yield ratio as a function of p(T) is consistent with a model based on the recombination of thermal s quarks up to p(T) similar to 4 GeV/c, but disagrees at higher transverse momenta. The measured nuclear modification factor, R-dAu, for the phi meson increases above unity at intermediate p(T), similar to that for pions and protons, while R-AA is suppressed due to the energy loss effect in central Au + Au collisions. Number of constituent quark scaling of both R-cp and nu(2) for the phi meson with respect to other hadrons in Au + Au collisions at root S-NN = 200 GeV at intermediate pT is observed. These observations support quark coalescence as being the dominant mechanism of hadronization in the intermediate p(T) region at RHIC.
作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Hollis, R. S.; Garcia-Solis, E. J.; Hofman, D. J.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Jones, P. G.; Elhalhuli, E.; Gaillard, L.; Burton, T. P.; Nelson, J. M.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Liu, J.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Okada, H.; Longacre, R. S.; Sorensen, P.; Christie, W.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Didenko, L.; Guryn, W.; Ludlam, T.; Van Buren, G.; Fachini, P.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.; Ng, M. J.; Yue, Q.; Trattner, A. L.] Univ Calif Berkeley, Berkeley, CA 94720 USA.
通讯机构:
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Callner, J.; Hollis, R. S.; Hofman, D. J.; Garcia-Solis, E.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Chattopadhyay, S.; Ganti, M. S.; Mazumdar, M. R. Dutta; Singaraju, R. N.; Nayak, T. K.; Ghosh, P.; Mohanty, B.; Pal, S. K.; Ahammed, Z.] Bhabha Atom Res Ctr, Ctr Variable Energy Cyclotron, Kolkata 700064, W Bengal, India.;[Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Jones, P. G.; Elhalhuli, E.; Gaillard, L.; Burton, T. P.; Nelson, J. M.; Barnsby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Chung, S. U.; Okada, H.; Longacre, R. S.; Lynn, D.; Sorensen, P.; Christie, W.; Zhang, H.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Didenko, L.; Guryn, W.; Ludlam, T.; Van Buren, G.; Fachini, P.] Brookhaven Natl Lab, Upton, NY 11973 USA.
通讯机构:
[Mohanty, B.] B;Bhabha Atom Res Ctr, Ctr Variable Energy Cyclotron, Kolkata 700064, W Bengal, India.
摘要:
We study the beam-energy and system-size dependence of phi meson production (using the hadronic decay mode phi -> K+ K-) by comparing the new results from Cu + Cu collisions and previously reported Au + Au collisions at root s(NN) = 62.4 and 200 GeV measured in the STAR experiment at RHIC. Data presented in this Letter are from mid-rapidity (vertical bar y vertical bar < 0.5) for 0.4 < p(T) < 5 GeV/c. At a given beam energy, the transverse momentum distributions for phi mesons are observed to be similar in yield and shape for Cu + Cu and Au + Au colliding systems with similar average numbers of participating nucleons. The phi meson yields in nucleus-nucleus collisions, normalized by the average number of participating nucleons, are found to be enhanced relative to those from p + p collisions. The enhancement for phi mesons lies between strange hadrons having net strangeness = 1 (K- and <(A)over bar>) and net strangeness = 2 (Xi). The enhancement for phi mesons is observed to be higher at root s(NN) = 200 GeV compared to 62.4 GeV. These observations for the produced phi(s (s) over bar) mesons clearly suggest that, at these collision energies, the source of enhancement of strange hadrons is related to the formation of a dense partonic medium in high energy nucleus-nucleus collisions and cannot be alone due to canonical suppression of their production in smaller systems. (C) 2009 Elsevier B.V. All rights reserved.
作者:
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Alakhverdyants, A. V.;Anderson, B. D.;...
期刊:
PHYSICAL REVIEW C,2009年80(4):- ISSN:2469-9985
通讯作者:
Abelev, B. I.
作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Hollis, R. S.; Kauder, K.; Garcia-Solis, E. J.; Hofman, D. J.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Jones, P. G.; Elhalhuli, E.; Gaillard, L.; Burton, T. P.; Nelson, J. M.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Okada, H.; Longacre, R. S.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Yip, K.; Didenko, L.; Guryn, W.; Ludlam, T.; Van Buren, G.; Fachini, P.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.; Ng, M. J.] Univ Calif Berkeley, Berkeley, CA 94720 USA.
通讯机构:
[Abelev, B. I.] A;Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA.
摘要:
The results of midrapidity (0 < y < 0.8) neutral pion spectra over an extended transverse momentum range (1 < p(T) < 12 GeV/c) in root s(NN) = 200 GeV Au + Au collisions, measured by the STAR experiment, are presented. The neutral pions are reconstructed from photons measured either by the STAR Barrel Electro-Magnetic Calorimeter or by the Time Projection Chamber via tracking of conversion electron-positron pairs. Our measurements are compared to previously published pi(+/-) and pi(0) results. The nuclear modification factors R-CP and R-AA of pi(0) are also presented as a function of p(T). In the most central Au + Au collisions, the binary collision scaled pi(0) yield at high p(T) is suppressed by a factor of about 5 compared to the expectation from the yield of p + p collisions. Such a large suppression is in agreement with previous observations for light quark mesons and is consistent with the scenario that partons suffer considerable energy loss in the dense medium formed in central nucleus-nucleus collisions at the Relativistic Heavy Ion Collider.
作者:
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Alakhverdyants, A. V.;Anderson, B. D.;...
期刊:
PHYSICAL REVIEW D,2009年80(11) ISSN:2470-0010
通讯作者:
Abelev, B. I.
作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Hollis, R. S.; Kauder, K.; Garcia-Solis, E. J.; Hofman, D. J.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Underwood, D. G.; Krueger, K.; Bridgeman, A.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Jones, P. G.; Elhalhuli, E.; Burton, T. P.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Okada, H.; Longacre, R. S.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Yip, K.; Didenko, L.; Guryn, W.; Van Buren, G.; Fachini, P.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.] Univ Calif Berkeley, Berkeley, CA 94720 USA.
通讯机构:
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
作者:
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Anderson, B. D.;Arkhipkin, D.;...
期刊:
PHYSICAL REVIEW C,2008年77(5) ISSN:2469-9985
通讯作者:
Abelev, B. I.
作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Callner, J.; Hollis, R. S.; Hofman, D. J.; Garcia-Solis, E.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Jones, P. G.; Elhalhuli, E.; Gaillard, L.; Timmins, A. R.; Burton, T. P.; Nelson, J. M.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Bueltmann, S.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Laue, F.; Bland, L. C.; Chung, S. U.; Okada, H.; Longacre, R. S.; Lynn, D.; Sorensen, P.; Christie, W.; Zhang, H.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Didenko, L.; Guryn, W.; Ludlam, T.; Potekhin, M.; Van Buren, G.; Fachini, P.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Relyea, D.; Hughes, E. W.] CALTECH, Pasadena, CA 91125 USA.
通讯机构:
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
摘要:
We present STAR results on the elliptic flow upsilon(2) Of charged hadrons, strange and multistrange particles from,root s(NN) = 200 GeV Au+Au collisions at the BNL Relativistic Heavy Ion Collider (RHIC). The detailed study of the centrality dependence of upsilon(2) over a broad transverse momentum range is presented. Comparisons of different analysis methods are made in order to estimate systematic uncertainties. To discuss the nonflow effect, we have performed the first analysis Of upsilon(2) with the Lee-Yang zero method for K-S(0) and A. In the relatively low PT region, P-T <= 2 GeV/c, a scaling with m(T) - m is observed for identified hadrons in each centrality bin studied. However, we do not observe nu 2(p(T))) scaled by the participant eccentricity to be independent of centrality. At higher PT, 2 1 <= PT <= 6 GeV/c, V2 scales with quark number for all hadrons studied. For the multistrange hadron Omega, which does not suffer appreciable hadronic interactions, the values of upsilon(2) are consistent with both m(T) - m scaling at low p(T) and number-of-quark scaling at intermediate p(T). As a function ofcollision centrality, an increase of p(T)-integrated upsilon(2) scaled by the participant eccentricity has been observed, indicating a stronger collective flow in more central Au+Au collisions.
作者:
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Anderson, B. D.;Arkhipkin, D.;...
期刊:
Physical Review C - Nuclear Physics,2008年77(6) ISSN:2469-9985
通讯作者:
Abelev, B. I.
作者机构:
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Callner, J.; Hollis, R. S.; Hofman, D. J.; Garcia-Solis, E.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Jones, P. G.; Elhalhuli, E.; Gaillard, L.; Timmins, A. R.; Burton, T. P.; Nelson, J. M.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Bueltmann, S.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Laue, F.; Bland, L. C.; Chung, S. U.; Okada, H.; Longacre, R. S.; Lynn, D.; Sorensen, P.; Christie, W.; Zhang, H.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Didenko, L.; Guryn, W.; Ludlam, T.; Potekhin, M.; Van Buren, G.; Fachini, P.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Hughes, E. W.] CALTECH, Pasadena, CA 91125 USA.
通讯机构:
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
摘要:
We present the first spin alignment measurements for the K*(0)(892) and phi(1020) vector mesons produced at midrapidity with transverse momenta up to 5 GeV/c at root s(NN) = 200 GeV at RHIC. The diagonal spin-density matrix elements with respect to the reaction plane in Au+Au collisions are rho(00) = 0.32 +/- 0.04 (stat) +/- 0.09 (syst) for the K*(0) (0.8 < p(T) < 5.0 GeV/c) and rho(00) = 0.34 +/- 0.02 (stat) +/- 0.03 (syst) for the phi (0.4 < p(T) < 5.0 GeV/c) and are constant with transverse momentum and collision centrality. The data are consistent with the unpolarized expectation of 1/3 and thus no evidence is found for the transfer of the orbital angular momentum of the colliding system to the vector-meson spins. Spin alignments for K-*0 and phi in Au+Au collisions were also measured with respect to the particle's production plane. The phi result, rho(00) = 0.41 +/- 0.02 (stat) +/- 0.04 (syst), is consistent with that in p+p collisions, rho(00) = 0.39 +/- 0.03 (stat) +/- 0.06 (syst), also measured in this work. The measurements thus constrain the possible size of polarization phenomena in the production dynamics of vector mesons.
作者机构:
[Abelev, B. I.] Univ Illinois, Chicago, IL 60607 USA.;Argonne Natl Lab, Argonne, IL 60439 USA.;Univ Birmingham, Birmingham, W Midlands, England.;Brookhaven Natl Lab, Upton, NY 11973 USA.;CALTECH, Pasadena, CA 91125 USA.
通讯机构:
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
作者:
Zuo, J. X.*;Chen, J. Y.;Cai, X. Z.;Ma, Y. G.;Liu, F.;...
期刊:
EUROPEAN PHYSICAL JOURNAL C,2008年55(3):463-467 ISSN:1434-6044
通讯作者:
Zuo, J. X.
作者机构:
[Ma, G. L.; Cai, X. Z.; Chen, J. H.; Zhong, C.; Zuo, J. X.; Ma, Y. G.] Chinese Acad Sci, Div Nucl Phys, Shanghai Inst Appl Sci, Shanghai 201800, Peoples R China.;[Chen, J. Y.; Liu, F.] Huazhong Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.;[Tang, A. H.; Sorensen, P.] Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA.;[Huang, H. Z.] Univ Calif Los Angeles, Los Angeles, CA 90095 USA.;[Zuo, J. X.] Chinese Acad Sci, Div Nucl Phys, Shanghai Inst Appl Sci, POB 800-204, Shanghai 201800, Peoples R China.
通讯机构:
[Zuo, J. X.] C;Chinese Acad Sci, Div Nucl Phys, Shanghai Inst Appl Sci, POB 800-204, Shanghai 201800, Peoples R China.
摘要:
The elliptic flow upsilon(2) and the fourth order anisotropic flow upsilon(4) of (Omega + (Omega) over bar) have been studied in the framework a parton-hadronic transport model, namely a multi-phase transport (AMPT) model, for Au-197 + Au-197 collisions at root(NN)-N-s = 200 GeV and 62.4 GeV. The transverse momentum (pT) and the transverse kinetic energy (m(T) - m(0)) dependence of upsilon(2) and upsilon(4) are presented. The calculation in the AMPT model seems consistent with the STAR data. The results show that the upsilon(2) of (Omega + (Omega) over bar) in 200 GeV obeys the constituent quark number scaling that has been observed for other mesons and baryons. Comparison of (Omega + (Omega) over bar) elliptic flow upsilon(2) in the default version of AMPT, the melting version of AMPT and the RQMD model calculation, shows that the parton cascade process is important to reproduce the sizeable upsilon(2), and the string melting AMPT model preferably reproduces (Omega + (Omega) over bar) elliptic flow upsilon(2) in Au-197 + Au-197 collisions at root(NN)-N-s = 200 GeV. The upsilon(2) of (Omega + (Omega) over bar) in the 62.4 and 200 GeV collisions seem similar, and the pT dependence of (Omega + (Omega) over bar) baryons' upsilon(4) in 62.4 GeV and 200 GeV looks also similar in the string melting AMPT model, which indicates that a similar partonic matter phase has been reached in both energies.
作者:
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Anderson, B. D.;Arkhipkin, D.;...
期刊:
Physical Review C - Nuclear Physics,2008年78(4) ISSN:2469-9985
通讯作者:
Abelev, B. I.
作者机构:
[Iordanova, A.; Abelev, B. I.; Callner, J.; Hollis, R. S.; Hofman, D. J.; Garcia-Solis, E.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Jones, P. G.; Elhalhuli, E.; Gaillard, L.; Timmins, A. R.; Burton, T. P.; Nelson, J. M.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Bueltmann, S.; Hallman, T. J.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Chung, S. U.; Okada, H.; Longacre, R. S.; Lynn, D.; Sorensen, P.; Christie, W.; Zhang, H.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Gordon, A.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Didenko, L.; Guryn, W.; Ludlam, T.; Van Buren, G.; Fachini, P.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Perkins, C.; Crawford, H. J.; Engelage, J.; Judd, E. G.; Ng, M. J.; Trattner, A. L.] Univ Calif Berkeley, Berkeley, CA 94720 USA.
通讯机构:
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
摘要:
We present the first measurements of the {rho}(770){sup 0},K*(892),{delta}(1232){sup ++},{sigma}(1385), and {lambda}(1520) resonances in d+Au collisions at {radical}(s{sub NN})=200 GeV, reconstructed via their hadronic decay channels using the STAR detector (the solenoidal tracker at the BNL Relativistic Heavy Ion Collider). The masses and widths of these resonances are studied as a function of transverse momentum p{sub T}. We observe that the resonance spectra follow a generalized scaling law with the transverse mass m{sub T}. The <p{sub T}> of resonances in minimum bias collisions are compared with the <p{sub T}> of {pi},K, and p. The {rho}{sup 0}/{pi}{sup -},K*/K{sup -},{delta}{sup ++}/p,{sigma}(1385)/{lambda}, and {lambda}(1520)/{lambda} ratios in d+Au collisions are compared with the measurements in minimum bias p+p interactions, where we observe that both measurements are comparable. The nuclear modification factors (R{sub dAu}) of the {rho}{sup 0},K*, and {sigma}* scale with the number of binary collisions (N{sub bin}) for p{sub T}> 1.2 GeV/c.