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32 results on '"Burton TP"'

1. Measurements of dihadron correlations relative to the event plane in Au+Au collisions at GeV

Author

Agakishiev, H, Aggarwal, MM, Ahammed, Z, Alakhverdyants, AV, Alekseev, I, Alford, J, Anderson, BD, Anson, CD, Arkhipkin, D, Averichev, GS, Balewski, J, Beavis, DR, Behera, NK, Bellwied, R, Betancourt, MJ, Betts, RR, Bhasin, A, Bhati, AK, Bichsel, H, Bielcik, J, Bielcikova, J, Biritz, B, Bland, LC, Borowski, W, Bouchet, J, Braidot, E, Brandin, AV, Bridgeman, A, Brovko, SG, Bruna, E, Bueltmann, S, Bunzarov, I, Burton, TP, Cai, XZ, Caines, H, de la Barca Sánchez, M Calderón, Cebra, D, Cendejas, R, Cervantes, MC, Chajecki, Z, Chaloupka, P, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, JY, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Choi, KE, Christie, W, Chung, P, Codrington, MJM, Corliss, R, Cramer, JG, Crawford, HJ, Dash, S, Leyva, A Davila, De Silva, LC, Debbe, RR, Dedovich, TG, Derevschikov, AA, de Souza, R Derradi, Didenko, L, Djawotho, P, Dogra, SM, Dong, X, Drachenberg, JL, Draper, JE, Dunlop, JC, Efimov, LG, Elnimr, M, Engelage, J, Eppley, G, Estienne, M, Eun, L, Evdokimov, O, Fatemi, R, Fedorisin, J, Feng, A, Fersch, RG, Filip, P, Finch, E, Fine, V, Fisyak, Y, Gagliardi, CA, Gangadharan, DR, Geromitsos, A, Geurts, F, Ghosh, P, Gorbunov, YN, Gordon, A, Grebenyuk, O, Grosnick, D, Guertin, SM, Gupta, A, Guryn, W, Haag, B, Hajkova, O, and Hamed, A

Subjects
Nuclear and Plasma Physics, Particle and High Energy Physics, Physical Sciences, relativistic heavy ion collisions, dihadron correlations, jet-medium interactions, anisotropic flow background, event plane, nucl-ex, nucl-th, NSD-Relativistic Nuclear Collisions, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics, Atomic, molecular and optical physics, Particle and high energy physics
Abstract

Dihadron azimuthal correlations containing a high transverse momentum (pT) trigger particle are sensitive to the properties of the nuclear medium created at RHIC through the strong interactions occurring between the traversing parton and the medium, i.e. jet-quenching. Previous measurements revealed a strong modification to dihadron azimuthal correlations in Au+Au collisions with respect to p+p and d+Au collisions. The modification increases with the collision centrality, suggesting a path-length or energy density dependence to the jet-quenching effect. This paper reports STAR measurements of dihadron azimuthal correlations in mid-central (20%-60%) Au+Au collisions at GeV as a function of the trigger particle's azimuthal angle relative to the event plane, . The azimuthal correlation is studied as a function of both the trigger and associated particle . The subtractions of the combinatorial background and anisotropic flow, assuming Zero Yield At Minimum (ZYAM), are described. The correlation results are first discussed with subtraction of the even harmonic (elliptic and quadrangular) flow backgrounds. The away-side correlation is strongly modified, and the modification varies with , with a double-peak structure for out-of-plane trigger particles. The near-side ridge (long range pseudo-rapidity correlation) appears to drop with increasing while the jet-like component remains approximately constant. The correlation functions are further studied with the subtraction of odd harmonic triangular flow background arising from fluctuations. It is found that the triangular flow, while responsible for the majority of the amplitudes, is not sufficient to explain the -dependence of the ridge or the away-side double-peak structure. The dropping ridge with could be attributed to a -dependent elliptic anisotropy; however, the physics mechanism of the ridge remains an open question. Even with a -dependent elliptic flow, the away-side correlation structure is robust. These results, with extensive systematic studies of the dihadron correlations as a function of , trigger and associated particle , and the pseudo-rapidity range , should provide stringent inputs to help understand the underlying physics mechanisms of jet-medium interactions in high energy nuclear collisions.

Published
2021

2. Beam-energy dependence of charge balance functions from Au + Au collisions at energies available at the BNL Relativistic Heavy Ion Collider

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandin, AV, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, de la Barca Sánchez, M Calderón, Campbell, JM, Cebra, D, Cervantes, MC, Chakaberia, I, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, JH, Chen, HF, Cheng, J, Cherney, M, Christie, W, Codrington, MJM, Contin, G, Crawford, HJ, Cui, X, Das, S, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, de Souza, R Derradi, di Ruzza, B, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Eppley, G, Esha, R, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Filip, P, Fisyak, Y, Flores, CE, Gagliardi, CA, Garand, D, Geurts, F, Gibson, A, Girard, M, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, Guryn, W, Hamad, A, Hamed, A, Han, L-X, Haque, R, Harris, JW, Heppelmann, S, Hirsch, A, Hoffmann, GW, Hofman, DJ, Horvat, S, Huang, B, Huang, X, Huang, HZ, Huck, P, and Humanic, TJ

Subjects
Nuclear and Plasma Physics, Particle and High Energy Physics, Physical Sciences, Nuclear and plasma physics
Abstract

Balance functions have been measured in terms of relative pseudorapidity (Δη) for charged particle pairs at the BNL Relativistic Heavy Ion Collider from Au + Au collisions at sNN=7.7GeV to 200 GeV using the STAR detector. These results are compared with balance functions measured at the CERN Large Hadron Collider from Pb + Pb collisions at sNN=2.76TeV by the ALICE Collaboration. The width of the balance function decreases as the collisions become more central and as the beam energy is increased. In contrast, the widths of the balance functions calculated using shuffled events show little dependence on centrality or beam energy and are larger than the observed widths. Balance function widths calculated using events generated by UrQMD are wider than the measured widths in central collisions and show little centrality dependence. The measured widths of the balance functions in central collisions are consistent with the delayed hadronization of a deconfined quark gluon plasma (QGP). The narrowing of the balance function in central collisions at sNN=7.7 GeV implies that a QGP is still being created at this relatively low energy.

Published
2016

3. Observation of Transverse Spin-Dependent Azimuthal Correlations of Charged Pion Pairs in p↑+p at s=200 GeV

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandin, AV, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cervantes, MC, Chakaberia, I, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Das, S, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, di Ruzza, B, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Eppley, G, Esha, R, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Z, Filip, P, Fisyak, Y, Flores, CE, Fulek, L, Gagliardi, CA, Garand, D, Geurts, F, Gibson, A, Girard, M, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, S, Gupta, A, Guryn, W, Hamad, A, Hamed, A, Haque, R, Harris, JW, He, L, Heppelmann, S, Hirsch, A, Hoffmann, GW, Hofman, DJ, Horvat, S, Huang, B, Huang, X, Huang, HZ, Huck, P, Humanic, TJ, and Igo, G

Subjects
Nuclear and Plasma Physics, Particle and High Energy Physics, Quantum Physics, Physical Sciences, STAR Collaboration, hep-ex, nucl-ex, Mathematical Sciences, Engineering, General Physics, Mathematical sciences, Physical sciences
Abstract

We report the observation of transverse polarization-dependent azimuthal correlations in charged pion pair production with the STAR experiment in p^{↑}+p collisions at RHIC. These correlations directly probe quark transversity distributions. We measure signals in excess of 5 standard deviations at high transverse momenta, at high pseudorapidities η>0.5, and for pair masses around the mass of the ρ meson. This is the first direct transversity measurement in p+p collisions.

Published
2015

4. Observation of Transverse Spin-Dependent Azimuthal Correlations of Charged Pion Pairs in p^{↑}+p at sqrt[s]=200  GeV.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandin, AV, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cervantes, MC, Chakaberia, I, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Das, S, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, di Ruzza, B, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Eppley, G, Esha, R, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Z, Filip, P, Fisyak, Y, Flores, CE, Fulek, L, Gagliardi, CA, Garand, D, Geurts, F, Gibson, A, Girard, M, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, S, Gupta, A, Guryn, W, Hamad, A, Hamed, A, Haque, R, Harris, JW, He, L, Heppelmann, S, Hirsch, A, Hoffmann, GW, Hofman, DJ, Horvat, S, Huang, B, Huang, X, Huang, HZ, Huck, P, Humanic, TJ, and Igo, G

Subjects
STAR Collaboration, hep-ex, nucl-ex, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

We report the observation of transverse polarization-dependent azimuthal correlations in charged pion pair production with the STAR experiment in p^{↑}+p collisions at RHIC. These correlations directly probe quark transversity distributions. We measure signals in excess of 5 standard deviations at high transverse momenta, at high pseudorapidities η>0.5, and for pair masses around the mass of the ρ meson. This is the first direct transversity measurement in p+p collisions.

Published
2015

5. Azimuthal Anisotropy in U+U and Au+Au Collisions at RHIC

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandin, AV, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cervantes, MC, Chakaberia, I, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Das, S, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, di Ruzza, B, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Eppley, G, Esha, R, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Z, Filip, P, Fisyak, Y, Flores, CE, Fulek, L, Gagliardi, CA, Garand, D, Geurts, F, Gibson, A, Girard, M, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, S, Gupta, A, Guryn, W, Hamad, A, Hamed, A, Haque, R, Harris, JW, He, L, Heppelmann, S, Hirsch, A, Hoffmann, GW, Hofman, DJ, Horvat, S, Huang, HZ, Huang, B, Huang, X, Huck, P, Humanic, TJ, and Igo, G

Subjects
Nuclear and Plasma Physics, Particle and High Energy Physics, Synchrotrons and Accelerators, Physical Sciences, STAR Collaboration, nucl-ex, nucl-th, Mathematical Sciences, Engineering, General Physics, Mathematical sciences, Physical sciences
Abstract

Collisions between prolate uranium nuclei are used to study how particle production and azimuthal anisotropies depend on initial geometry in heavy-ion collisions. We report the two- and four-particle cumulants, v_{2}{2} and v_{2}{4}, for charged hadrons from U+U collisions at sqrt[s_{NN}]=193  GeV and Au+Au collisions at sqrt[s_{NN}]=200  GeV. Nearly fully overlapping collisions are selected based on the energy deposited by spectators in zero degree calorimeters (ZDCs). Within this sample, the observed dependence of v_{2}{2} on multiplicity demonstrates that ZDC information combined with multiplicity can preferentially select different overlap configurations in U+U collisions. We also show that v_{2} vs multiplicity can be better described by models, such as gluon saturation or quark participant models, that eliminate the dependence of the multiplicity on the number of binary nucleon-nucleon collisions.

Published
2015

6. Azimuthal Anisotropy in U+U and Au+Au Collisions at RHIC.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandin, AV, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cervantes, MC, Chakaberia, I, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Das, S, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, di Ruzza, B, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Eppley, G, Esha, R, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Z, Filip, P, Fisyak, Y, Flores, CE, Fulek, L, Gagliardi, CA, Garand, D, Geurts, F, Gibson, A, Girard, M, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, S, Gupta, A, Guryn, W, Hamad, A, Hamed, A, Haque, R, Harris, JW, He, L, Heppelmann, S, Hirsch, A, Hoffmann, GW, Hofman, DJ, Horvat, S, Huang, HZ, Huang, B, Huang, X, Huck, P, Humanic, TJ, and Igo, G

Subjects
STAR Collaboration, nucl-ex, nucl-th, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

Collisions between prolate uranium nuclei are used to study how particle production and azimuthal anisotropies depend on initial geometry in heavy-ion collisions. We report the two- and four-particle cumulants, v_{2}{2} and v_{2}{4}, for charged hadrons from U+U collisions at sqrt[s_{NN}]=193  GeV and Au+Au collisions at sqrt[s_{NN}]=200  GeV. Nearly fully overlapping collisions are selected based on the energy deposited by spectators in zero degree calorimeters (ZDCs). Within this sample, the observed dependence of v_{2}{2} on multiplicity demonstrates that ZDC information combined with multiplicity can preferentially select different overlap configurations in U+U collisions. We also show that v_{2} vs multiplicity can be better described by models, such as gluon saturation or quark participant models, that eliminate the dependence of the multiplicity on the number of binary nucleon-nucleon collisions.

Published
2015

7. Precision Measurement of the Longitudinal Double-Spin Asymmetry for Inclusive Jet Production in Polarized Proton Collisions at s=200 GeV

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cudd, AB, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, and Gupta, A

Subjects
STAR Collaboration, hep-ex, nucl-ex, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

We report a new measurement of the midrapidity inclusive jet longitudinal double-spin asymmetry, A_{LL}, in polarized pp collisions at center-of-mass energy sqrt[s]=200  GeV. The STAR data place stringent constraints on polarized parton distribution functions extracted at next-to-leading order from global analyses of inclusive deep-inelastic scattering (DIS), semi-inclusive DIS, and RHIC pp data. The measured asymmetries provide evidence at the 3σ level for positive gluon polarization in the Bjorken-x region x>0.05.

Published
2015

8. Precision Measurement of the Longitudinal Double-Spin Asymmetry for Inclusive Jet Production in Polarized Proton Collisions at sqrt[s]=200  GeV.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cudd, AB, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, and Gupta, A

Subjects
STAR Collaboration, hep-ex, nucl-ex, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

We report a new measurement of the midrapidity inclusive jet longitudinal double-spin asymmetry, A_{LL}, in polarized pp collisions at center-of-mass energy sqrt[s]=200  GeV. The STAR data place stringent constraints on polarized parton distribution functions extracted at next-to-leading order from global analyses of inclusive deep-inelastic scattering (DIS), semi-inclusive DIS, and RHIC pp data. The measured asymmetries provide evidence at the 3σ level for positive gluon polarization in the Bjorken-x region x>0.05.

Published
2015

9. Observation of Charge Asymmetry Dependence of Pion Elliptic Flow and the Possible Chiral Magnetic Wave in Heavy-Ion Collisions

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandin, AV, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cervantes, MC, Chakaberia, I, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Das, S, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, di Ruzza, B, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Eppley, G, Esha, R, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Z, Filip, P, Fisyak, Y, Flores, CE, Fulek, L, Gagliardi, CA, Garand, D, Geurts, F, Gibson, A, Girard, M, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, S, Gupta, A, Guryn, W, Hamad, A, Hamed, A, Haque, R, Harris, JW, He, L, Heppelmann, S, Hirsch, A, Hoffmann, GW, Hofman, DJ, Horvat, S, Huang, HZ, Huang, B, Huang, X, Huck, P, Humanic, TJ, and Igo, G

Subjects
Pediatric Research Initiative, STAR Collaboration, nucl-ex, nucl-th, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

We present measurements of π(-) and π(+) elliptic flow, v(2), at midrapidity in Au+Au collisions at √[s(NN)]=200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV, as a function of event-by-event charge asymmetry, A(ch), based on data from the STAR experiment at RHIC. We find that π(-) (π(+)) elliptic flow linearly increases (decreases) with charge asymmetry for most centrality bins at √[s(NN)]=27  GeV and higher. At √[s(NN)]=200  GeV, the slope of the difference of v(2) between π(-) and π(+) as a function of A(ch) exhibits a centrality dependence, which is qualitatively similar to calculations that incorporate a chiral magnetic wave effect. Similar centrality dependence is also observed at lower energies.

Published
2015

10. Observation of Charge Asymmetry Dependence of Pion Elliptic Flow and the Possible Chiral Magnetic Wave in Heavy-Ion Collisions.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandin, AV, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cervantes, MC, Chakaberia, I, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Das, S, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, di Ruzza, B, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Eppley, G, Esha, R, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Z, Filip, P, Fisyak, Y, Flores, CE, Fulek, L, Gagliardi, CA, Garand, D, Geurts, F, Gibson, A, Girard, M, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, S, Gupta, A, Guryn, W, Hamad, A, Hamed, A, Haque, R, Harris, JW, He, L, Heppelmann, S, Hirsch, A, Hoffmann, GW, Hofman, DJ, Horvat, S, Huang, HZ, Huang, B, Huang, X, Huck, P, Humanic, TJ, and Igo, G

Subjects
STAR Collaboration, Pediatric Research Initiative, nucl-ex, nucl-th, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

We present measurements of π(-) and π(+) elliptic flow, v(2), at midrapidity in Au+Au collisions at √[s(NN)]=200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV, as a function of event-by-event charge asymmetry, A(ch), based on data from the STAR experiment at RHIC. We find that π(-) (π(+)) elliptic flow linearly increases (decreases) with charge asymmetry for most centrality bins at √[s(NN)]=27  GeV and higher. At √[s(NN)]=200  GeV, the slope of the difference of v(2) between π(-) and π(+) as a function of A(ch) exhibits a centrality dependence, which is qualitatively similar to calculations that incorporate a chiral magnetic wave effect. Similar centrality dependence is also observed at lower energies.

Published
2015

11. ΛΛ Correlation Function in Au+Au Collisions at sNN=200 GeV

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, Guryn, W, and Haag, B

Subjects
(STAR Collaboration), nucl-ex, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

We present ΛΛ correlation measurements in heavy-ion collisions for Au+Au collisions at sqrt[s_{NN}]=200  GeV using the STAR experiment at the Relativistic Heavy-Ion Collider. The Lednický-Lyuboshitz analytical model has been used to fit the data to obtain a source size, a scattering length and an effective range. Implications of the measurement of the ΛΛ correlation function and interaction parameters for dihyperon searches are discussed.

Published
2015

12. ΛΛ Correlation function in Au+Au collisions at √[S(NN)]=200  GeV.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, Guryn, W, and Haag, B

Subjects
(STAR Collaboration), nucl-ex, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

We present ΛΛ correlation measurements in heavy-ion collisions for Au+Au collisions at sqrt[s_{NN}]=200  GeV using the STAR experiment at the Relativistic Heavy-Ion Collider. The Lednický-Lyuboshitz analytical model has been used to fit the data to obtain a source size, a scattering length and an effective range. Implications of the measurement of the ΛΛ correlation function and interaction parameters for dihyperon searches are discussed.

Published
2015

13. Observation of D0 meson nuclear modifications in Au+Au collisions at sqrt[s(NN)] = 200 GeV.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, and Guryn, W

Subjects
STAR Collaboration, nucl-ex, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

We report the first measurement of charmed-hadron (D(0)) production via the hadronic decay channel (D(0) → K(-) + π(+)) in Au+Au collisions at sqrt[s(NN)] = 200 GeV with the STAR experiment. The charm production cross section per nucleon-nucleon collision at midrapidity scales with the number of binary collisions, N(bin), from p+p to central Au+Au collisions. The D(0) meson yields in central Au + Au collisions are strongly suppressed compared to those in p+p scaled by N(bin), for transverse momenta p(T) > 3 GeV/c, demonstrating significant energy loss of charm quarks in the hot and dense medium. An enhancement at intermediate p(T) is also observed. Model calculations including strong charm-medium interactions and coalescence hadronization describe our measurements.

Published
2014

14. Observation of D0 meson nuclear modifications in Au+Au collisions at sqrt[s(NN)] = 200 GeV.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, and Guryn, W

Subjects
STAR Collaboration, nucl-ex, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

We report the first measurement of charmed-hadron (D(0)) production via the hadronic decay channel (D(0) → K(-) + π(+)) in Au+Au collisions at sqrt[s(NN)] = 200 GeV with the STAR experiment. The charm production cross section per nucleon-nucleon collision at midrapidity scales with the number of binary collisions, N(bin), from p+p to central Au+Au collisions. The D(0) meson yields in central Au + Au collisions are strongly suppressed compared to those in p+p scaled by N(bin), for transverse momenta p(T) > 3 GeV/c, demonstrating significant energy loss of charm quarks in the hot and dense medium. An enhancement at intermediate p(T) is also observed. Model calculations including strong charm-medium interactions and coalescence hadronization describe our measurements.

Published
2014

15. Beam energy dependence of moments of the net-charge multiplicity distributions in Au+Au collisions at RHIC.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Balewski, J, Banerjee, A, Barnovska, Z, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Corliss, R, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Grosnick, D, Guo, Y, Gupta, A, Gupta, S, Guryn, W, and Haag, B

Subjects
STAR Collaboration, nucl-ex, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

We report the first measurements of the moments--mean (M), variance (σ(2)), skewness (S), and kurtosis (κ)--of the net-charge multiplicity distributions at midrapidity in Au+Au collisions at seven energies, ranging from sqrt[sNN]=7.7 to 200 GeV, as a part of the Beam Energy Scan program at RHIC. The moments are related to the thermodynamic susceptibilities of net charge, and are sensitive to the location of the QCD critical point. We compare the products of the moments, σ(2)/M, Sσ, and κσ(2), with the expectations from Poisson and negative binomial distributions (NBDs). The Sσ values deviate from the Poisson baseline and are close to the NBD baseline, while the κσ(2) values tend to lie between the two. Within the present uncertainties, our data do not show nonmonotonic behavior as a function of collision energy. These measurements provide a valuable tool to extract the freeze-out parameters in heavy-ion collisions by comparing with theoretical models.

Published
2014

16. Measurement of longitudinal spin asymmetries for weak boson production in polarized proton-proton collisions at RHIC.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Balewski, J, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, and Gupta, A

Subjects
(STAR Collaboration), Clinical Research, nucl-ex, hep-ex, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

We report measurements of single- and double-spin asymmetries for W^{±} and Z/γ^{*} boson production in longitudinally polarized p+p collisions at sqrt[s]=510  GeV by the STAR experiment at RHIC. The asymmetries for W^{±} were measured as a function of the decay lepton pseudorapidity, which provides a theoretically clean probe of the proton's polarized quark distributions at the scale of the W mass. The results are compared to theoretical predictions, constrained by polarized deep inelastic scattering measurements, and show a preference for a sizable, positive up antiquark polarization in the range 0.05

Published
2014

17. Beam energy dependence of moments of the net-charge multiplicity distributions in Au+Au collisions at RHIC.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Balewski, J, Banerjee, A, Barnovska, Z, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Corliss, R, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Grosnick, D, Guo, Y, Gupta, A, Gupta, S, Guryn, W, and Haag, B

Subjects
STAR Collaboration, nucl-ex, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

We report the first measurements of the moments--mean (M), variance (σ(2)), skewness (S), and kurtosis (κ)--of the net-charge multiplicity distributions at midrapidity in Au+Au collisions at seven energies, ranging from sqrt[sNN]=7.7 to 200 GeV, as a part of the Beam Energy Scan program at RHIC. The moments are related to the thermodynamic susceptibilities of net charge, and are sensitive to the location of the QCD critical point. We compare the products of the moments, σ(2)/M, Sσ, and κσ(2), with the expectations from Poisson and negative binomial distributions (NBDs). The Sσ values deviate from the Poisson baseline and are close to the NBD baseline, while the κσ(2) values tend to lie between the two. Within the present uncertainties, our data do not show nonmonotonic behavior as a function of collision energy. These measurements provide a valuable tool to extract the freeze-out parameters in heavy-ion collisions by comparing with theoretical models.

Published
2014

18. Measurement of longitudinal spin asymmetries for weak boson production in polarized proton-proton collisions at RHIC.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Balewski, J, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, and Gupta, A

Subjects
(STAR Collaboration), Clinical Research, nucl-ex, hep-ex, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

We report measurements of single- and double-spin asymmetries for W^{±} and Z/γ^{*} boson production in longitudinally polarized p+p collisions at sqrt[s]=510  GeV by the STAR experiment at RHIC. The asymmetries for W^{±} were measured as a function of the decay lepton pseudorapidity, which provides a theoretically clean probe of the proton's polarized quark distributions at the scale of the W mass. The results are compared to theoretical predictions, constrained by polarized deep inelastic scattering measurements, and show a preference for a sizable, positive up antiquark polarization in the range 0.05

Published
2014

19. Beam-Energy Dependence of Charge Separation along the Magnetic Field in Au+Au Collisions at RHIC

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, and Guryn, W

Subjects
STAR Collaboration, nucl-ex, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

Local parity-odd domains are theorized to form inside a quark-gluon plasma which has been produced in high-energy heavy-ion collisions. The local parity-odd domains manifest themselves as charge separation along the magnetic field axis via the chiral magnetic effect. The experimental observation of charge separation has previously been reported for heavy-ion collisions at the top RHIC energies. In this Letter, we present the results of the beam-energy dependence of the charge correlations in Au+Au collisions at midrapidity for center-of-mass energies of 7.7, 11.5, 19.6, 27, 39, and 62.4 GeV from the STAR experiment. After background subtraction, the signal gradually reduces with decreased beam energy and tends to vanish by 7.7 GeV. This implies the dominance of hadronic interactions over partonic ones at lower collision energies.

Published
2014

20. Beam-energy dependence of charge separation along the magnetic field in Au+Au collisions at RHIC.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, and Guryn, W

Subjects
STAR Collaboration, nucl-ex, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

Local parity-odd domains are theorized to form inside a quark-gluon plasma which has been produced in high-energy heavy-ion collisions. The local parity-odd domains manifest themselves as charge separation along the magnetic field axis via the chiral magnetic effect. The experimental observation of charge separation has previously been reported for heavy-ion collisions at the top RHIC energies. In this Letter, we present the results of the beam-energy dependence of the charge correlations in Au+Au collisions at midrapidity for center-of-mass energies of 7.7, 11.5, 19.6, 27, 39, and 62.4 GeV from the STAR experiment. After background subtraction, the signal gradually reduces with decreased beam energy and tends to vanish by 7.7 GeV. This implies the dominance of hadronic interactions over partonic ones at lower collision energies.

Published
2014

21. Dielectron Mass Spectra from Au+Au Collisions at sNN=200 GeV

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Barnovska, Z, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Grosnick, D, Guo, Y, Gupta, A, Gupta, S, Guryn, W, Haag, B, Hajkova, O, and Hamed, A

Subjects
STAR Collaboration, hep-ex, nucl-ex, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

We report the STAR measurements of dielectron (e(+)e(-)) production at midrapidity (|y(ee)|

Published
2014

22. Dielectron mass spectra from Au+Au collisions at √[s(NN)]=200  GeV.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Barnovska, Z, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Grosnick, D, Guo, Y, Gupta, A, Gupta, S, Guryn, W, Haag, B, Hajkova, O, and Hamed, A

Subjects
STAR Collaboration, hep-ex, nucl-ex, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

We report the STAR measurements of dielectron (e(+)e(-)) production at midrapidity (|y(ee)|

Published
2014

23. Beam-Energy Dependence of the Directed Flow of Protons, Antiprotons, and Pions in Au+Au Collisions

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, and Guryn, W

Subjects
(STAR Collaboration), nucl-ex, hep-ex, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

Rapidity-odd directed flow (v1) measurements for charged pions, protons, and antiprotons near midrapidity (y=0) are reported in sNN=7.7, 11.5, 19.6, 27, 39, 62.4, and 200 GeV Au+Au collisions as recorded by the STAR detector at the Relativistic Heavy Ion Collider. At intermediate impact parameters, the proton and net-proton slope parameter dv1/dy|y=0 shows a minimum between 11.5 and 19.6 GeV. In addition, the net-proton dv1/dy|y=0 changes sign twice between 7.7 and 39 GeV. The proton and net-proton results qualitatively resemble predictions of a hydrodynamic model with a first-order phase transition from hadronic matter to deconfined matter, and differ from hadronic transport calculations.

Published
2014

24. Beam-energy dependence of the directed flow of protons, antiprotons, and pions in Au+Au collisions.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, and Guryn, W

Subjects
(STAR Collaboration), nucl-ex, hep-ex, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

Rapidity-odd directed flow (v1) measurements for charged pions, protons, and antiprotons near midrapidity (y=0) are reported in sNN=7.7, 11.5, 19.6, 27, 39, 62.4, and 200 GeV Au+Au collisions as recorded by the STAR detector at the Relativistic Heavy Ion Collider. At intermediate impact parameters, the proton and net-proton slope parameter dv1/dy|y=0 shows a minimum between 11.5 and 19.6 GeV. In addition, the net-proton dv1/dy|y=0 changes sign twice between 7.7 and 39 GeV. The proton and net-proton results qualitatively resemble predictions of a hydrodynamic model with a first-order phase transition from hadronic matter to deconfined matter, and differ from hadronic transport calculations.

Published
2014

25. Jet-Hadron Correlations in sNN=200 GeV p+p and Central Au+Au Collisions

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, and Guryn, W

Subjects
STAR Collaboration, nucl-ex, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

Azimuthal angular correlations of charged hadrons with respect to the axis of a reconstructed (trigger) jet in Au+Au and p+p collisions at √[s(NN)]=200  GeV in STAR are presented. The trigger jet population in Au+Au collisions is biased toward jets that have not interacted with the medium, allowing easier matching of jet energies between Au+Au and p+p collisions while enhancing medium effects on the recoil jet. The associated hadron yield of the recoil jet is significantly suppressed at high transverse momentum (pTassoc) and enhanced at low pTassoc in 0%-20% central Au+Au collisions compared to p+p collisions, which is indicative of medium-induced parton energy loss in ultrarelativistic heavy-ion collisions.

Published
2014

26. Jet-hadron correlations in √[s(NN)]=200  GeV p+p and central Au+Au collisions.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Banerjee, A, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Contin, G, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Greiner, L, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, and Guryn, W

Subjects
STAR Collaboration, nucl-ex, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

Azimuthal angular correlations of charged hadrons with respect to the axis of a reconstructed (trigger) jet in Au+Au and p+p collisions at √[s(NN)]=200  GeV in STAR are presented. The trigger jet population in Au+Au collisions is biased toward jets that have not interacted with the medium, allowing easier matching of jet energies between Au+Au and p+p collisions while enhancing medium effects on the recoil jet. The associated hadron yield of the recoil jet is significantly suppressed at high transverse momentum (pTassoc) and enhanced at low pTassoc in 0%-20% central Au+Au collisions compared to p+p collisions, which is indicative of medium-induced parton energy loss in ultrarelativistic heavy-ion collisions.

Published
2014

27. Energy Dependence of Moments of Net-Proton Multiplicity Distributions at RHIC

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Balewski, J, Banerjee, A, Barnovska, Z, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Corliss, R, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Grosnick, D, Guo, Y, Gupta, A, Gupta, S, Guryn, W, and Haag, B

Subjects
STAR Collaboration, nucl-ex, hep-ex, hep-lat, hep-ph, nucl-th, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

We report the beam energy (sqrt[sNN]=7.7-200  GeV) and collision centrality dependence of the mean (M), standard deviation (σ), skewness (S), and kurtosis (κ) of the net-proton multiplicity distributions in Au+Au collisions. The measurements are carried out by the STAR experiment at midrapidity (|y|

Published
2014

28. Energy dependence of moments of net-proton multiplicity distributions at RHIC.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Balewski, J, Banerjee, A, Barnovska, Z, Beavis, DR, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chwastowski, J, Codrington, MJM, Corliss, R, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Dilks, C, Ding, F, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Engelage, J, Engle, KS, Eppley, G, Eun, L, Evdokimov, O, Fatemi, R, Fazio, S, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Girard, M, Gliske, S, Grosnick, D, Guo, Y, Gupta, A, Gupta, S, Guryn, W, and Haag, B

Subjects
STAR Collaboration, nucl-ex, hep-ex, hep-lat, hep-ph, nucl-th, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

We report the beam energy (sqrt[sNN]=7.7-200  GeV) and collision centrality dependence of the mean (M), standard deviation (σ), skewness (S), and kurtosis (κ) of the net-proton multiplicity distributions in Au+Au collisions. The measurements are carried out by the STAR experiment at midrapidity (|y|

Published
2014

29. Measurement of J/ψ Azimuthal Anisotropy in Au+Au Collisions at sNN=200 GeV

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, E, Averichev, GS, Balewski, J, Banerjee, A, Barnovska, Z, Beavis, DR, Bellwied, R, Betancourt, MJ, Betts, RR, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bruna, E, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Cai, XZ, Caines, H, de la Barca Sánchez, M Calderón, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, JY, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chung, P, Chwastowski, J, Codrington, MJM, Corliss, R, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Leyva, A Davila, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, de Souza, R Derradi, Dhamija, S, di Ruzza, B, Didenko, L, Ding, F, Dion, A, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Elnimr, M, Engelage, J, Eppley, G, Eun, L, Evdokimov, O, Fatemi, R, Fazio, S, Fedorisin, J, Fersch, RG, Filip, P, Finch, E, Fisyak, Y, Flores, E, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Gliske, S, and Grebenyuk, OG

Subjects
Anisotropy, Elementary Particles, Gold, Quantum Theory, STAR Collaboration, nucl-ex, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

The measurement of J/ψ azimuthal anisotropy is presented as a function of transverse momentum for different centralities in Au+Au collisions at sqrt[s(NN)]=200 GeV. The measured J/ψ elliptic flow is consistent with zero within errors for transverse momentum between 2 and 10 GeV/c. Our measurement suggests that J/ψ particles with relatively large transverse momenta are not dominantly produced by coalescence from thermalized charm quarks, when comparing to model calculations.

Published
2013

30. Measurement of J/ψ azimuthal anisotropy in Au+Au collisions at sqrt[s(NN)]=200 GeV.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Alford, J, Anson, CD, Aparin, A, Arkhipkin, D, Aschenauer, E, Averichev, GS, Balewski, J, Banerjee, A, Barnovska, Z, Beavis, DR, Bellwied, R, Betancourt, MJ, Betts, RR, Bhasin, A, Bhati, AK, Bhattarai, P, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Borowski, W, Bouchet, J, Brandin, AV, Brovko, SG, Bruna, E, Bültmann, S, Bunzarov, I, Burton, TP, Butterworth, J, Cai, XZ, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Cendejas, R, Cervantes, MC, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, HF, Chen, JH, Chen, JY, Chen, L, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Chung, P, Chwastowski, J, Codrington, MJM, Corliss, R, Cramer, JG, Crawford, HJ, Cui, X, Das, S, Davila Leyva, A, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derradi de Souza, R, Dhamija, S, di Ruzza, B, Didenko, L, Ding, F, Dion, A, Djawotho, P, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Elnimr, M, Engelage, J, Eppley, G, Eun, L, Evdokimov, O, Fatemi, R, Fazio, S, Fedorisin, J, Fersch, RG, Filip, P, Finch, E, Fisyak, Y, Flores, E, Gagliardi, CA, Gangadharan, DR, Garand, D, Geurts, F, Gibson, A, Gliske, S, and Grebenyuk, OG

Subjects
STAR Collaboration, Gold, Anisotropy, Elementary Particles, Quantum Theory, nucl-ex, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

The measurement of J/ψ azimuthal anisotropy is presented as a function of transverse momentum for different centralities in Au+Au collisions at sqrt[s(NN)]=200 GeV. The measured J/ψ elliptic flow is consistent with zero within errors for transverse momentum between 2 and 10 GeV/c. Our measurement suggests that J/ψ particles with relatively large transverse momenta are not dominantly produced by coalescence from thermalized charm quarks, when comparing to model calculations.

Published
2013

31. Hadronic resonance production in d+Au collisions at sNN=200 GeV measured at the BNL Relativistic Heavy Ion Collider

Author

Abelev, BI, Aggarwal, MM, Ahammed, Z, Anderson, BD, Arkhipkin, D, Averichev, GS, Bai, Y, Balewski, J, Barannikova, O, Barnby, LS, Baudot, J, Baumgart, S, Beavis, DR, Bellwied, R, Benedosso, F, Betts, RR, Bhardwaj, S, Bhasin, A, Bhati, AK, Bichsel, H, Bielcik, J, Bielcikova, J, Biritz, B, Bland, LC, Bombara, M, Bonner, BE, Botje, M, Bouchet, J, Braidot, E, Brandin, AV, Bruna, Bueltmann, S, Burton, TP, Bystersky, M, Cai, XZ, Caines, H, de la Barca Sánchez, M Calderón, Callner, J, Catu, O, Cebra, D, Cendejas, R, Cervantes, MC, Chajecki, Z, Chaloupka, P, Chattopdhyay, S, Chen, HF, Chen, JH, Chen, JY, Cheng, J, Cherney, M, Chikanian, A, Choi, KE, Christie, W, Chung, SU, Clarke, RF, Codrington, MJM, Coffin, JP, Cormier, TM, Cosentino, MR, Cramer, JG, Crawford, HJ, Das, D, Dash, S, Daugherity, M, De Silva, C, Dedovich, TG, DePhillips, M, Derevschikov, AA, de Souza, R Derradi, Didenko, L, Djawotho, P, Dogra, SM, Dong, X, Drachenberg, JL, Draper, JE, Du, F, Dunlop, JC, Mazumdar, MR Dutta, Edwards, WR, Efimov, LG, Elhalhuli, E, Elnimr, M, Emelianov, V, Engelage, J, Eppley, G, Erazmus, B, Estienne, M, Eun, L, Fachini, P, Fatemi, R, Fedorisin, J, Feng, A, Filip, P, Finch, E, Fine, V, Fisyak, Y, Gagliardi, CA, Gaillard, L, Gangaharan, DR, and Ganti, MS

Subjects
Nuclear and Plasma Physics, Particle and High Energy Physics, Synchrotrons and Accelerators, Physical Sciences, nucl-ex, Nuclear and plasma physics
Abstract

We present the first measurements of the ρ(770)0,K*(892), Δ(1232)++,Σ(1385), and Λ(1520) resonances in d+Au collisions at sNN=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 pT. We observe that the resonance spectra follow a generalized scaling law with the transverse mass mT. The pT of resonances in minimum bias collisions are compared with the pT of π,K, and p̄. The ρ0/π-,K*/K-,Δ++/p,Σ(1385)/Λ, and Λ(1520)/Λ 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 (RdAu) of the ρ0,K*, and Σ* scale with the number of binary collisions (Nbin) for pT 1.2 GeV/c. © 2008 The American Physical Society.

Published
2008

32. Neutral kaon interferometry in Au+Au collisions at sNN=200 GeV

Author

Abelev, BI, Aggarwal, MM, Ahammed, Z, Amonett, J, Anderson, BD, Anderson, M, Arkhipkin, D, Averichev, GS, Bai, Y, Balewski, J, Barannikova, O, Barnby, LS, Baudot, J, Bekele, S, Belaga, VV, Bellingeri-Laurikainen, A, Bellwied, R, Benedosso, F, Bhardwaj, S, Bhasin, A, Bhati, AK, Bichsel, H, Bielcik, J, Bielcikova, J, Bland, LC, Blyth, S-L, Bonner, BE, Botje, M, Bouchet, J, Brandin, AV, Bravar, A, Burton, TP, Bystersky, M, Cadman, RV, Cai, XZ, Caines, H, de la Barca Sánchez, M Calderón, Castillo, J, Catu, O, Cebra, D, Chajecki, Z, Chaloupka, P, Chattopadhyay, S, Chen, HF, Chen, JH, Cheng, J, Cherney, M, Chikanian, A, Christie, W, Coffin, JP, Cormier, TM, Cosentino, MR, Cramer, JG, Crawford, HJ, Das, D, Das, S, Dash, S, Daugherity, M, de Moura, MM, Dedovich, TG, DePhillips, M, Derevschikov, AA, Didenko, L, Dietel, T, Djawotho, P, Dogra, SM, Dong, WJ, Dong, X, Draper, JE, Du, F, Dunin, VB, Dunlop, JC, Mazumdar, MR Dutta, Eckardt, V, Edwards, WR, Efimov, LG, Emelianov, V, Engelage, J, Eppley, G, Erazmus, B, Estienne, M, Fachini, P, Fatemi, R, Fedorisin, J, Filimonov, K, Filip, P, Finch, E, Fine, V, Fisyak, Y, Fu, J, Gagliardi, CA, Gaillard, L, Ganti, MS, Ghazikhanian, V, Ghosh, P, Gonzalez, JE, Gorbunov, YG, Gos, H, Grebenyuk, O, and Grosnick, D

Subjects
Nuclear and Plasma Physics, Particle and High Energy Physics, Physical Sciences, nucl-ex, Nuclear and plasma physics
Abstract

We present the first statistically meaningful results from two-Ks0 interferometry in heavy-ion collisions at sNN=200 GeV. A model that takes the effect of the strong interaction into account has been used to fit the measured correlation function. The effects of single and coupled channels were explored. At the mean transverse mass mT =1.07 GeV, we obtain the values R=4.09±0.46(stat)±0.31(sys) fm and λ=0.92±0.23(stat) ±0.13(sys), where R and λ are the invariant radius and chaoticity parameters, respectively. The results are qualitatively consistent with mT systematics established with pions in a scenario characterized by a strong collective flow. © 2006 The American Physical Society.

Published
2006

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