作者机构:
[Gou, Qingdong; Li, Yong] Department of Physics, Huazhong Normal University, Wuhan 430079, China;College of Mathematics and Physics, Jinggangshan University, Ji′an 343009, China;[Gou, Qingdong] College of Mathematics and Physics, Jinggangshan University, Jian 343009, China
通讯机构:
[Yong Li] D;Department of Physics, Huazhong Normal University, Wuhan 430079, China
摘要:
There are three points in the preceding Comment. We agree with the first point, and we point out that the second and third points are due to a misunderstanding.
作者机构:
[Li, Yong; Gou, Qingdong] Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.;[Gou, Qingdong] Jinggangshan Univ, Coll Math & Phys, Jian 343009, Jiangxi, Peoples R China.
通讯机构:
[Gou, Qingdong] H;Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.
摘要:
We investigate for the existence of the weakly bound He-He-Ca molecules. By employing the best empirical interaction between each pair of particles, the Schrödinger equation for the triatomic system is solved using hyperspherical coordinates in the adiabatic approximation. The bound states are found for each of the 3He- 3He- 40Ca, 3He- 4He- 40Ca, and 4He- 4He- 40Ca trimers, respectively. The binding energies of such molecules are estimated. We discuss the features of the channel functions associated with the hyperspherical potential curves of each system to obtain insight into the geometry of the molecules.
作者:
Agakishiev, G.*;Aggarwal, M. M.;Ahammed, Z.;Alakhverdyants, A. V.;Alekseev, I.;...
期刊:
PHYSICAL REVIEW C,2012年86(1) ISSN:2469-9985
通讯作者:
Agakishiev, G.
作者机构:
[Kechechyan, A.; Kizka, V.; Agakishiev, G.; Averichev, G. S.; Bunzarov, I.; Efimov, L. G.; Panebratsev, Y.; Alakhverdyants, A. V.; Shahaliev, E.; Rogachevskiy, O. V.; Fedorisin, J.; Zoulkarneeva, Y.; Tokarev, M.; Filip, P.; Lednicky, R.; Dedovich, T. G.; Vokal, S.] Joint Inst Nucl Res, Dubna 141980, Russia.;[Underwood, D. G.; Krueger, K.; Bridgeman, A.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Longacre, R. S.; Webb, J. C.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Burton, T. P.; Dunlop, J. C.; Gordon, A.; Landgraf, J. M.; Yip, K.; Didenko, L.; Guryn, W.; Mitrovski, M. K.; Van Buren, G.; 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.;[Sanchez, M. Calderon de la Barca; Mall, O. I.; Draper, J. E.; Cebra, D.; Brovko, S. G.; Sangaline, E.; Reed, R.; Romero, J. L.; Salur, S.; Haag, B.; Liu, H.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Agakishiev, G.] J;Joint Inst Nucl Res, Dubna 141980, Russia.
摘要:
We present STAR measurements of azimuthal anisotropy by means of the two- and four-particle cumulants nu(2) (nu(2){2} and nu(2){4}) for Au + Au and Cu + Cu collisions at center-of-mass energies root S-NN = 62.4 and 200 GeV. The difference between nu(2){2}(2) and nu(2){4}(2) is related to nu(2) fluctuations (sigma(nu 2)) and nonflow (delta(2)). We present an upper limit to sigma(nu 2)/nu 2. Following the assumption that eccentricity fluctuations sigma(epsilon) dominate nu(2) fluctuations nu(2)/sigma nu(2) approximate to epsilon/sigma epsilon we deduce the nonflow implied for several models of eccentricity fluctuations that would be required for consistency with nu(2){2} and nu(2){4}. We also present results on the ratio of nu(2) to eccentricity.
作者机构:
[Kechechyan, A.; Kizka, V.; Agakishiev, G.; Averichev, G. S.; Bunzarov, I.; Efimov, L. G.; Panebratsev, Y.; Alakhverdyants, A. V.; Shahaliev, E.; Rogachevskiy, O. V.; Fedorisin, J.; Zoulkarneeva, Y.; Tokarev, M.; Filip, P.; Lednicky, R.; Dedovich, T. G.; Vokal, S.] Joint Inst Nucl Res, Dubna 141980, Russia.;[Underwood, D. G.; Krueger, K.; Bridgeman, A.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Jones, P. G.; 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.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Longacre, R. S.; Webb, J. C.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Burton, T. P.; Dunlop, J. C.; Gordon, A.; Landgraf, J. M.; Yip, K.; Didenko, L.; Guryn, W.; Mitrovski, M. K.; Van Buren, G.; Lee, J. H.] Brookhaven Natl Lab, Upton, NY 11973 USA.;[Mall, O. I.; Draper, J. E.; Cebra, D.; Brovko, S. G.; Sangaline, E.; Reed, R.; de la Barca Sanchez, M. Calderon; Romero, J. L.; Salur, S.; Haag, B.; Liu, H.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Agakishiev, G.] J;Joint Inst Nucl Res, Dubna 141980, Russia.
作者:
Agakishiev, G.*;Aggarwal, M. M.;Ahammed, Z.;Alakhverdyants, A. V.;Alekseev, I.;...
期刊:
PHYSICAL REVIEW C,2012年86(6) ISSN:2469-9985
通讯作者:
Agakishiev, G.
作者机构:
[Kechechyan, A.; Kizka, V.; Agakishiev, G.; Averichev, G. S.; Bunzarov, I.; Efimov, L. G.; Panebratsev, Y.; Alakhverdyants, A. V.; Shahaliev, E.; Rogachevskiy, O. V.; Fedorisin, J.; Zoulkarneeva, Y.; Tokarev, M.; Filip, P.; Lednicky, R.; Dedovich, T. G.; Vokal, S.] Joint Inst Nucl Res, Dubna 141980, Russia.;[Underwood, D. G.; Krueger, K.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Longacre, R. S.; Webb, J. C.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Burton, T. P.; Dunlop, J. C.; Gordon, A.; Landgraf, J. M.; Yip, K.; Didenko, L.; Mitrovski, M. K.; Van Buren, G.; 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.;[Sanchez, M. Calderon de la Barca; Mall, O. I.; Draper, J. E.; Cebra, D.; Brovko, S. G.; Sangaline, E.; Reed, R.; Romero, J. L.; Salur, S.; Haag, B.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Agakishiev, G.] J;Joint Inst Nucl Res, Dubna 141980, Russia.
摘要:
We present two-dimensional (2D) two-particle angular correlations measured with the STAR detector on relative pseudorapidity eta and azimuth phi for charged particles from Au-Au collisions at root s(NN) = 62 and 200 GeV with transverse momentum p(t) >= 0.15 GeV/c, vertical bar eta vertical bar <= 1, and 2 pi in azimuth. Observed correlations include a same-side (relative azimuth <pi/2) 2D peak, a closely related away-side azimuth dipole, and an azimuth quadrupole conventionally associated with elliptic flow. The same-side 2D peak and away-side dipole are explained by semihard parton scattering and fragmentation (minijets) in proton-proton and peripheral nucleus-nucleus collisions. Those structures follow N-N binary-collision scaling in Au-Au collisions until midcentrality, where a transition to a qualitatively different centrality trend occurs within one 10% centrality bin. Above the transition point the number of same-side and away-side correlated pairs increases rapidly relative to binary-collision scaling, the eta width of the same-side 2D peak also increases rapidly (eta elongation), and the phi width actually decreases significantly. Those centrality trends are in marked contrast with conventional expectations for jet quenching in a dense medium. The observed centrality trends are compared to perturbative QCD predictions computed in HIJING, which serve as a theoretical baseline, and to the expected trends for semihard parton scattering and fragmentation in a thermalized opaque medium predicted by theoretical calculations and phenomenological models. We are unable to reconcile a semihard parton scattering and fragmentation origin for the observed correlation structure and centrality trends with heavy-ion collision scenarios that invoke rapid parton thermalization. If the collision system turns out to be effectively opaque to few-GeV partons the present observations would be inconsistent with the minijet picture discussed here. DOI: 10.1103/PhysRevC.86.064902
作者机构:
[Pruthi, N. K.; Bhati, A. K.; Aggarwal, M. M.] Panjab Univ, Chandigarh 160014, India.;[Underwood, D. G.; Krueger, K.; Bridgeman, A.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Fine, V.; Fisyak, Y.; Videbk, F.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Longacre, R. S.; Webb, J. C.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Burton, T. P.; Dunlop, J. C.; Gordon, A.; Landgraf, J. M.; Love, W. A.; Yip, K.; Didenko, L.; Guryn, W.; Van Buren, G.; 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.;[Mall, O. I.; Draper, J. E.; Cebra, D.; Brovko, S. G.; Sangaline, E.; Reed, R.; de la Barca Sanchez, M. Calderon; Romero, J. L.; Salur, S.; Haag, B.; Liu, H.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Aggarwal, M. M.] P;Panjab Univ, Chandigarh 160014, India.
作者:
Aggarwal, M. M.*;Ahammed, Z.;Alakhverdyants, A. V.;Alekseev, I.;Alford, J.;...
期刊:
PHYSICAL REVIEW C,2011年83(2) ISSN:2469-9985
通讯作者:
Aggarwal, M. M.
作者机构:
[Pruthi, N. K.; Bhati, A. K.; Aggarwal, M. M.] Panjab Univ, Chandigarh 160014, India.;[Underwood, D. G.; Krueger, K.; Bridgeman, A.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Longacre, R. S.; Webb, J. C.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Burton, T. P.; Dunlop, J. C.; Gordon, A.; Landgraf, J. M.; Tlusty, D.; Love, W. A.; Yip, K.; Didenko, L.; Guryn, W.; Van Buren, G.; 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.;[Sanchez, M. Calderon de la Barca; Mall, O. I.; Draper, J. E.; Cebra, D.; Brovko, S. G.; Sangaline, E.; Reed, R.; Romero, J. L.; Salur, S.; Haag, B.; Liu, H.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Aggarwal, M. M.] P;Panjab Univ, Chandigarh 160014, India.
摘要:
We present results on strange and multistrange particle production in Au + Au collisions at root s(NN) = 62.4 GeV as measured with the STAR detector at RHIC. Midrapidity transverse momentum spectra and integrated yields of K-S(0), Lambda, Xi, and Omega and their antiparticles are presented for different centrality classes. The particle yields and ratios follow a smooth energy dependence. Chemical freeze-out parameters, temperature, baryon chemical potential, and strangeness saturation factor obtained from the particle yields are presented. Intermediate transverse momentum (p(T)) phenomena are discussed based on the ratio of the measured baryon-to-meson spectra and nuclear modification factor. The centrality dependence of various measurements presented show a similar behavior as seen in Au + Au collisions at root s(NN) = 200 GeV.
作者:
Agakishiev, H.*;Aggarwal, M. M.;Ahammed, Z.;Alakhverdyants, A. V.;Alekseev, I.;...
期刊:
Nature,2011年473(7347):353-356 ISSN:1476-4687
通讯作者:
Agakishiev, H.
作者机构:
[Kechechyan, A.; Kizka, V.; Agakishiev, H.; Averichev, G. S.; Bunzarov, I.; Efimov, L. G.; Panebratsev, Y.; Alakhverdyants, A. V.; Shahaliev, E.; Rogachevskiy, O. V.; Fedorisin, J.; Zoulkarneev, R.; Zoulkarneeva, Y.; Tokarev, M.; Filip, P.; Lednicky, R.; Dedovich, T. G.; Vokal, S.] Joint Inst Nucl Res, Dubna 141980, Russia.;[Bhati, A. K.; K. Pruthi, N.; Aggarwal, M. M.] Panjab Univ, Chandigarh 160014, India.;[Sakrejda, I.; Wieman, H.; Masui, H.; Schmah, A. M.; Porter, J.; Sichtermann, E. P.; Naglis, M.; Grebenyuk, O. G.; Sun, X. M.; Ploskon, M. A.; Thomas, J. H.; Poskanzer, A. M.; Ritter, H. G.; Zhang, Y.; Powell, C. B.; Hjort, E.; Jacobs, P.; Kiryluk, J.; Klein, S. R.; Olson, D.; Odyniec, G.; Matis, H. S.; Symons, T. J. M.; Ahammed, Z.; Dong, X.] Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA.;[Koroleva, L.; Svirida, D. N.; Morozov, B.; Bordyuzhin, I. G.; Alekseev, I.] Alikhanov Inst Theoret & Expt Phys, Moscow 117218, Russia.;[Joseph, J.; Vanfossen, J. A., Jr.; Pandit, Y.; Zhang, W. M.; Kumar, L.; Anderson, B. D.; Margetis, S.; Alford, J.; Keane, D.; Bouchet, J.; Subba, N. L.] Kent State Univ, Kent, OH 44242 USA.
通讯机构:
Joint Institute for Nuclear Research, Russian Federation
摘要:
High-energy nuclear collisions create an energy density similar to that of the Universe microseconds after the Big Bang(1); in both cases, matter and antimatter are formed with comparable abundance. However, the relatively short-lived expansion in nuclear collisions allows antimatter to decouple quickly from matter, and avoid annihilation. Thus, a high-energy accelerator of heavy nuclei provides an efficient means of producing and studying antimatter. The antimatter helium-4 nucleus ((4)(He) over bar), also known as the anti-alpha ((alpha) over bar), consists of two antiprotons and two antineutrons (baryon number B = -4). It has not been observed previously, although the alpha-particle was identified a century ago by Rutherford and is present in cosmic radiation at the ten per cent level(2). Antimatter nuclei with B -1 have been observed only as rare products of interactions at particle accelerators, where the rate of antinucleus production in high-energy collisions decreases by a factor of about 1,000 with each additional antinucleon(3-5). Here we report the observation of (4)<(He) over bar, the heaviest observed antinucleus to date. In total, 18 (4)(He) over bar counts were detected at the STAR experiment at the Relativistic Heavy Ion Collider (RHIC; ref. 6) in 10(9) recorded gold-on-gold (Au+Au) collisions at centre-of-mass energies of 200 GeV and 62 GeV per nucleon-nucleon pair. The yield is consistent with expectations from thermodynamic(7) and coalescent nucleosynthesis(8) models, providing an indication of the production rate of even heavier antimatter nuclei and a benchmark for possible future observations of (4)(He) over bar in cosmic radiation.
作者机构:
Argonne National Laboratory, Argonne, IL 60439, United States;Brookhaven National Laboratory, Upton, NY 11973, United States;University of California, Berkeley, CA 94720, United States;University of California, Davis, CA 95616, United States;University of California, Los Angeles, CA 90095, United States
通讯机构:
Joint Institute for Nuclear Research, Russian Federation
作者:
Agakishiev, H.*;Aggarwal, M. M.;Ahammed, Z.;Alakhverdyants, A. V.;Alekseev, I.;...
期刊:
PHYSICAL REVIEW D,2011年83(5) ISSN:2470-0010
通讯作者:
Agakishiev, H.
作者机构:
[Kechechyan, A.; Kizka, V.; Agakishiev, H.; Averichev, G. S.; Bunzarov, I.; Efimov, L. G.; Panebratsev, Y.; Alakhverdyants, A. V.; Shahaliev, E.; Rogachevskiy, O. V.; Fedorisin, J.; Zoulkarneev, R.; Zoulkarneeva, Y.; Tokarev, M.; Filip, P.; Lednicky, R.; Dedovich, T. G.; Vokal, S.] Joint Inst Nucl Res, Dubna 141980, Russia.;[Underwood, D. G.; Krueger, K.; Bridgeman, A.; Spinka, H. M.] Argonne Natl Lab, Argonne, IL 60439 USA.;[Ullrich, T.; Pile, P.; Lamont, M. A. C.; LeVine, M. J.; Ljubicic, T.; Xu, Z.; Ogawa, A.; Ruan, L.; Tang, A. H.; Videbaek, F.; Fine, V.; Fisyak, Y.; Beavis, D. R.; Lauret, J.; Bland, L. C.; Longacre, R. S.; Webb, J. C.; Sorensen, P.; Christie, W.; Arkhipkin, D.; Debbe, R. R.; Lebedev, A.; Burton, T. P.; Dunlop, J. C.; Gordon, A.; Landgraf, J. M.; Love, W. A.; Yip, K.; Didenko, L.; Guryn, W.; Van Buren, G.; 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.;[Sanchez, M. Calderon de la Barca; Mall, O. I.; Draper, J. E.; Cebra, D.; Brovko, S. G.; Sangaline, E.; Reed, R.; Romero, J. L.; Salur, S.; Haag, B.; Liu, H.] Univ Calif Davis, Davis, CA 95616 USA.
通讯机构:
[Agakishiev, H.] A;Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA.
摘要:
We present the measurement of nonphotonic electron production at high transverse momentum (p(T) > 2.5 GeV/c) in p + p collisions at root s = 200 GeV using data recorded during 2005 and 2008 by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The measured cross sections from the two runs are consistent with each other despite a large difference in photonic background levels due to different detector configurations. We compare the measured nonphotonic electron cross sections with previously published RHIC data and perturbative quantum chromodynamics calculations. Using the relative contributions of B and D mesons to nonphotonic electrons, we determine the integrated cross sections of electrons (e++e-2/2) at 3 GeV/c < p(T) < 10 GeV/c from bottom and charm meson decays to be [(d sigma((B -> e)+(B -> D -> e))/(dy(e))](ye=0) 4.0 +/- 0.5(stat) +/- 1.1(syst) nb and [(d sigma(D -> e))/(dy(e))](ye=0) = 6.2 +/- 0.7(stat) +/- 1.5(syst) nb, respectively.