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：
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.
作者：
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Anderson, B. D.;Arkhipkin, D.;...
期刊：
PHYSICAL REVIEW C,2008年77(4) ISSN：2469-9985
通讯作者：
Abelev, B. I.
作者机构：
[Balewski, J.; 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.; 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.] A;Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 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.;[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.;[Hughes, E. W.] CALTECH, Pasadena, CA 91125 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(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.; Garcia-Solis, E.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Underwood, D. G.; Krueger, K.] 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.;[Bueltmann, S.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Bland, L. C.; Chung, S. U.; Christie, W.; Dunlop, J. C.; Gordon, A.; DePhillips, M.; Guryn, W.; Fachini, P.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Ullrich, T.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Relyea, D.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Lauret, J.; Laue, F.; Okada, H.; Longacre, R. S.; Lynn, D.; Sorensen, P.; Zhang, H.; Hughes, E. W.; Lebedev, A.; Perevoztchikov, V.; Landgraf, J. M.; Love, W. A.; Ludlam, T.; Potekhin, M.; Van Buren, G.] CALTECH, Pasadena, CA 91125 USA.
通讯机构：
[Abelev, B. I.] U;Univ Illinois, Chicago, IL 60607 USA.
摘要：
Photoproduction reactions occur when the electromagnetic field of a relativistic heavy ion interacts with another heavy ion. The STAR Collaboration presents a measurement of rho(0) and direct pi(+)pi(-) photoproduction in ultraperipheral relativistic heavy ion collisions at root s(NN) = 200 GeV. We observe both exclusive photoproduction and photoproduction accompanied by mutual Coulomb excitation. We find a coherent cross section of sigma(AuAu -> Au*Au*rho(0)) = 530 +/- 19(stat.) +/- 57(syst.) mb, in accord with theoretical calculations based on a Glauber approach, but considerably below the predictions of a color dipole model. The rho 0 transverse momentum spectrum (p(T)(2)) is fit by a double exponential curve including both coherent and incoherent coupling to the target nucleus; we find sigma(inc)/sigma(coh) = 0.29 +/- 0.03 (stat.) +/- 0.08 (syst.). The ratio of direct pi(+)pi(-) to rho(0) production is comparable to that observed in gamma(p) collisions at HERA and appears to be independent of photon energy. Finally, the measured rho(0) spin helicity matrix elements agree within errors with the expected s-channel helicity conservation.
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.;[Bueltmann, S.; Beavis, D. R.; Bland, L. C.; Chung, S. U.; Christie, W.; Dunlop, J. C.; DePhillips, M.; Didenko, L.; Rakness, 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.
作者：
Abelev, B. I.*;Aggarwal, M. M.;Ahammed, Z.;Anderson, B. D.;Arkhipkin, D.;...
期刊：
PHYSICAL REVIEW C,2007年76(6) ISSN：2469-9985
通讯作者：
Abelev, B. I.
作者机构：
[Iordanova, A.; Abelev, B. I.; Barannikova, O.; Callner, J.; Hoffman, A. M.; Hollis, R. S.; Garcia-Solis, E.; Betts, R. R.; Suarez, M. C.] Univ Illinois, Chicago, IL 60607 USA.;[Underwood, D. G.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Bombara, M.; Gaillard, L.; Timmins, A. R.; Barnby, L. S.] Univ Birmingham, Birmingham, W Midlands, England.;[Ullrich, T.; LeVine, M. J.; Ljubicic, T.; Fine, V.; Fisyak, Y.; Lauret, J.; Laue, F.; Chung, S. U.; Longacre, R. S.; Lynn, D.; Christie, W.; Zhang, H.; Lebedev, A.; Dunlop, J. C.; Perevoztchikov, V.; Landgraf, J. M.; DePhillips, M.; Love, W. A.; Didenko, L.; Ludlam, T.; Potekhin, M.; Van Buren, G.; Fachini, P.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Relyea, D.] 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 study of the energy dependence of pt angular correlations inferred from event-wisemean transversemomentum < p(t)> fluctuations in heavy ion collisions. We compare our large-acceptance measurements at CM energies root s(NN) = 19.6, 62.4, 130 and 200 GeV to SPS measurements at 12.3 and 17.3 GeV. p(t) angular correlation structure suggests that the principal source of pt correlations and fluctuations is minijets (minimum-bias parton fragments). We observe a dramatic increase in correlations and fluctuations from SPS to RHIC energies, increasing linearly with 1n root s(NN) from the onset of observable jet-related < p(t)> fluctuations near 10 GeV.
作者机构：
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.;Univ Calif Berkeley, Berkeley, CA 94720 USA.
通讯机构：
[Adams, J.] A;Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA.
作者：
Adams, J.*;Aggarwal, M. M.;Ahammed, Z.;Amonett, J.;Anderson, B. D.;...
期刊：
JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS,2007年34(5):799-816 ISSN：0954-3899
通讯作者：
Adams, J.
作者机构：
[Adams, J.] Univ Birmingham, Birmingham, W Midlands, England.;Panjab Univ, Chandigarh 160014, India.;Bhabha Atom Res Ctr, Ctr Variable Energy Cyclotron, Kolkata 700064, W Bengal, India.;Kent State Univ, Kent, OH 44242 USA.;Univ Calif Davis, Davis, CA 95616 USA.
通讯机构：
[Adams, J.] U;Univ Birmingham, Birmingham, W Midlands, England.
摘要：
Measurements of two-particle correlations on transverse momentum p(t) for Au-Au collisions at root s(NN) = 130 GeV are presented. Significant large-momentum-scale correlations are observed for charged primary hadrons with 0.15 <= p(t) <= 2 GeV/c and pseudorapidity vertical bar eta vertical bar <= 1.3. Such correlations were not observed in a similar study at lower energy and are not predicted by theoretical collision models. Their direct relation to mean-p(t) fluctuations measured in the same angular acceptance is demonstrated. Positive correlations are observed for pairs of particles which have large p(t) values while negative correlations occur for pairs in which one particle has large p(t) and the other has much lower p(t). The correlation amplitudes per final state particle increase with collision centrality. The observed correlations are consistent with a scenario in which the transverse momentum of hadrons associated with initial-stage semi-hard parton scattering is dissipated by the medium to lower p(t).
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：
Abelev, B. I.*;Adams, J.;Aggarwal, M. M.;Ahammed, Z.;Amonett, J.;...
期刊：
PHYSICAL REVIEW C,2007年76(5) ISSN：2469-9985
通讯作者：
Abelev, B. I.
作者机构：
[Abelev, B. I.] Yale Univ, New Haven, CT 06520 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.] Y;Yale Univ, New Haven, CT 06520 USA.
摘要：
We determine rapidity asymmetry in the production of charged pions, protons, and antiprotons for large transverse momentum (p(T)) for d+Au collisions at root s(NN)=200 GeV. The rapidity asymmetry is defined as the ratio of particle yields at backward rapidity (Au beam direction) to those at forward rapidity (d beam direction). The identified hadrons are measured in the rapidity regions |y|< 0.5 and 0.5 <|y|< 1.0 for the p(T) range 2.5 < p(T)< 10 GeV/c. We observe significant rapidity asymmetry for charged pion and proton+antiproton production in both the rapidity regions. The asymmetry is larger for 0.5 <|y|< 1.0 than for |y|< 0.5 and is almost independent of particle type. The measurements are compared to various model predictions employing multiple scattering, energy loss, nuclear shadowing, saturation effects, and recombination and also to a phenomenological parton model. We find that asymmetries are sensitive to model parameters and show model preference. The rapidity dependence of pi(-)/pi(+) and (p) over bar /p ratios in peripheral d+Au and forward neutron-tagged events are used to study the contributions of valence quarks and gluons to particle production at high p(T).
作者：
Xiao, Z. G.*;Dong, X.;Liu, F.;Luo, X. F.;Wu, K. J.;...
期刊：
JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS,2007年34(8):S915-S919 ISSN：0954-3899
通讯作者：
Xiao, Z. G.
作者机构：
[Xiao, Z. G.] Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China.;Univ Sci & Technol China, Hefei 230026, Peoples R China.;Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.;Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA.
通讯机构：
[Xiao, Z. G.] C;Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China.
会议名称：
19th International Conference on Ultra-Relativistic Necleus-Nucleus Collisions
会议时间：
NOV 14-20, 2006
会议地点：
Shanghai, PEOPLES R CHINA
会议主办单位：
Chinese Acad Sci, Inst Modern Phys, Lanzhou 730000, Peoples R China.^Univ Sci & Technol China, Hefei 230026, Peoples R China.^Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Peoples R China.^Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA.
