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2,596 results on '"Das"'

1. Hexagonal Close-Packed Polar-Skyrmion Lattice in Ultrathin Ferroelectric PbTiO3 Films

Author

Yuan, Shuai, Chen, Zuhuang, Prokhorenko, Sergei, Nahas, Yousra, Bellaiche, Laurent, Liu, Chenhan, Xu, Bin, Chen, Lang, Das, Sujit, and Martin, Lane W

Subjects
Electricity, Phase Transition, Static Electricity, Temperature, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

Polar skyrmions are topologically stable, swirling polarization textures with particlelike characteristics, which hold promise for next-generation, nanoscale logic and memory. However, the understanding of how to create ordered polar skyrmion lattice structures and how such structures respond to applied electric fields, temperature, and film thickness remains elusive. Here, using phase-field simulations, the evolution of polar topology and the emergence of a phase transition to a hexagonal close-packed skyrmion lattice is explored through the construction of a temperature-electric field phase diagram for ultrathin ferroelectric PbTiO_{3} films. The hexagonal-lattice skyrmion crystal can be stabilized under application of an external, out-of-plane electric field which carefully adjusts the delicate interplay of elastic, electrostatic, and gradient energies. In addition, the lattice constants of the polar skyrmion crystals are found to increase with film thickness, consistent with expectation from Kittel's law. Our studies pave the way for the development of novel ordered condensed matter phases assembled from topological polar textures and related emergent properties in nanoscale ferroelectrics.

Published
2023

2. Structural Chirality of Polar Skyrmions Probed by Resonant Elastic X-Ray Scattering

Author

McCarter, Margaret R, Kim, Kook Tae, Stoica, Vladimir A, Das, Sujit, Klewe, Christoph, Donoway, Elizabeth P, Burn, David M, Shafer, Padraic, Rodolakis, Fanny, Gonçalves, Mauro AP, Gómez-Ortiz, Fernando, Íñiguez, Jorge, García-Fernández, Pablo, Junquera, Javier, Lovesey, Stephen W, van der Laan, Gerrit, Park, Se Young, Freeland, John W, Martin, Lane W, Lee, Dong Ryeol, and Ramesh, Ramamoorthy

Subjects
Physical Sciences, Condensed Matter Physics, Mathematical Sciences, Engineering, General Physics, Mathematical sciences, Physical sciences
Abstract

An escalating challenge in condensed-matter research is the characterization of emergent order-parameter nanostructures such as ferroelectric and ferromagnetic skyrmions. Their small length scales coupled with complex, three-dimensional polarization or spin structures makes them demanding to trace out fully. Resonant elastic x-ray scattering (REXS) has emerged as a technique to study chirality in spin textures such as skyrmions and domain walls. It has, however, been used to a considerably lesser extent to study analogous features in ferroelectrics. Here, we present a framework for modeling REXS from an arbitrary arrangement of charge quadrupole moments, which can be applied to nanostructures in materials such as ferroelectrics. With this, we demonstrate how extended reciprocal space scans using REXS with circularly polarized x rays can probe the three-dimensional structure and chirality of polar skyrmions. Measurements, bolstered by quantitative scattering calculations, show that polar skyrmions of mixed chirality coexist, and that REXS allows valuation of relative fractions of right- and left-handed skyrmions. Our quantitative analysis of the structure and chirality of polar skyrmions highlights the capability of REXS for establishing complex topological structures toward future application exploits.

Published
2022

3. Angstrom-Resolved Interfacial Structure in Buried Organic-Inorganic Junctions

Author

Schwartz, Craig P, Raj, Sumana L, Jamnuch, Sasawat, Hull, Chris J, Miotti, Paolo, Lam, Royce K, Nordlund, Dennis, Uzundal, Can B, Pemmaraju, Chaitanya Das, Mincigrucci, Riccardo, Foglia, Laura, Simoncig, Alberto, Coreno, Marcello, Masciovecchio, Claudio, Giannessi, Luca, Poletto, Luca, Principi, Emiliano, Zuerch, Michael, Pascal, Tod A, Drisdell, Walter S, and Saykally, Richard J

Subjects
Physical Sciences, Mathematical Sciences, Engineering, General Physics, Mathematical sciences, Physical sciences
Abstract

Charge transport processes at interfaces play a crucial role in many processes. Here, the first soft x-ray second harmonic generation (SXR SHG) interfacial spectrum of a buried interface (boron-Parylene N) is reported. SXR SHG shows distinct spectral features that are not observed in x-ray absorption spectra, demonstrating its extraordinary interfacial sensitivity. Comparison to electronic structure calculations indicates a boron-organic separation distance of 1.9 Å, with changes of less than 1 Å resulting in easily detectable SXR SHG spectral shifts (ca. hundreds of milli-electron volts).

Published
2021

4. Search for Supersymmetry with a Compressed Mass Spectrum in Events with a Soft τ Lepton, a Highly Energetic Jet, and Large Missing Transverse Momentum in Proton-Proton Collisions at s=13 TeV

Author

Sirunyan, AM, Tumasyan, A, Adam, W, Ambrogi, F, Bergauer, T, Brandstetter, J, Dragicevic, M, Erö, J, Del Valle, A Escalante, Flechl, M, Frühwirth, R, Jeitler, M, Krammer, N, Krätschmer, I, Liko, D, Madlener, T, Mikulec, I, Rad, N, Schieck, J, Schöfbeck, R, Spanring, M, Spitzbart, D, Waltenberger, W, Wulz, C-E, Zarucki, M, Drugakov, V, Mossolov, V, Gonzalez, J Suarez, Darwish, MR, De Wolf, EA, Di Croce, D, Janssen, X, Lelek, A, Pieters, M, Sfar, H Rejeb, Van Haevermaet, H, Van Mechelen, P, Van Putte, S, Van Remortel, N, Blekman, F, Bols, ES, Chhibra, SS, D’Hondt, J, De Clercq, J, Lontkovskyi, D, Lowette, S, Marchesini, I, Moortgat, S, Python, Q, Skovpen, K, Tavernier, S, Van Doninck, W, Van Mulders, P, Beghin, D, Bilin, B, Brun, H, Clerbaux, B, De Lentdecker, G, Delannoy, H, Dorney, B, Favart, L, Grebenyuk, A, Kalsi, AK, Popov, A, Postiau, N, Starling, E, Thomas, L, Vander Velde, C, Vanlaer, P, Vannerom, D, Cornelis, T, Dobur, D, Khvastunov, I, Niedziela, M, Roskas, C, Tytgat, M, Verbeke, W, Vermassen, B, Vit, M, Bondu, O, Bruno, G, Caputo, C, David, P, Delaere, C, Delcourt, M, Giammanco, A, Lemaitre, V, Prisciandaro, J, Saggio, A, Marono, M Vidal, Vischia, P, Zobec, J, Alves, FL, Alves, GA, Silva, G Correia, Hensel, C, Moraes, A, Teles, P Rebello, Chagas, E Belchior Batista Das, and Carvalho, W

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

The first search for supersymmetry in events with an experimental signature of one soft, hadronically decaying τ lepton, one energetic jet from initial-state radiation, and large transverse momentum imbalance is presented. These event signatures are consistent with direct or indirect production of scalar τ leptons (τ[over ˜]) in supersymmetric models that exhibit coannihilation between the τ[over ˜] and the lightest neutralino (χ[over ˜]_{1}^{0}), and that could generate the observed relic density of dark matter. The data correspond to an integrated luminosity of 77.2  fb^{-1} of proton-proton collisions at sqrt[s]=13  TeV collected with the CMS detector at the LHC in 2016 and 2017. The results are interpreted in a supersymmetric scenario with a small mass difference (Δm) between the chargino (χ[over ˜]_{1}^{±}) or next-to-lightest neutralino (χ[over ˜]_{2}^{0}), and the χ[over ˜]_{1}^{0}. The mass of the τ[over ˜] is assumed to be the average of the χ[over ˜]_{1}^{±} and χ[over ˜]_{1}^{0} masses. The data are consistent with standard model background predictions. Upper limits at 95% confidence level are set on the sum of the χ[over ˜]_{1}^{±}, χ[over ˜]_{2}^{0}, and τ[over ˜] production cross sections for Δm(χ[over ˜]_{1}^{±},χ[over ˜]_{1}^{0})=50  GeV, resulting in a lower limit of 290 GeV on the mass of the χ[over ˜]_{1}^{±}, which is the most stringent to date and surpasses the bounds from the LEP experiments.

Published
2020

6. First Observation of the Directed Flow of D0 and D0¯ in Au+Au Collisions at sNN=200 GeV

Author

Adam, J, Adamczyk, L, Adams, JR, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Aschenauer, EC, Ashraf, MU, Atetalla, FG, Attri, A, Averichev, GS, Bairathi, V, Barish, K, Bassill, AJ, Behera, A, Bellwied, R, Bhasin, A, Bhati, AK, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Brandenburg, JD, Brandin, AV, Bryslawskyj, J, Bunzarov, I, Butterworth, J, Caines, H, de la Barca Sánchez, M Calderón, Cebra, D, Chakaberia, I, Chaloupka, P, Chan, BK, Chang, F-H, Chang, Z, Chankova-Bunzarova, N, Chatterjee, A, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Csanád, M, Das, S, Dedovich, TG, Deppner, IM, Derevschikov, AA, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Dunlop, JC, Edmonds, T, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Y, Filip, P, Finch, E, Fisyak, Y, Fulek, L, Gagliardi, CA, Galatyuk, T, Geurts, F, Gibson, A, Gopal, K, Greiner, L, Grosnick, D, Gupta, A, Guryn, W, Hamad, AI, Hamed, A, Harris, JW, He, L, Heppelmann, S, Herrmann, N, Holub, L, Hong, Y, Horvat, S, Huang, B, Huang, HZ, and Huang, SL

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

We report the first measurement of rapidity-odd directed flow (v_{1}) for D^{0} and D^{0}[over ¯] mesons at midrapidity (|y|

Published
2019

7. First Observation of the Directed Flow of D^{0} and D^{0}[over ¯] in Au+Au Collisions at sqrt[s_{NN}]=200  GeV.

Author

Adam, J, Adamczyk, L, Adams, JR, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Aschenauer, EC, Ashraf, MU, Atetalla, FG, Attri, A, Averichev, GS, Bairathi, V, Barish, K, Bassill, AJ, Behera, A, Bellwied, R, Bhasin, A, Bhati, AK, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Brandenburg, JD, Brandin, AV, Bryslawskyj, J, Bunzarov, I, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Chakaberia, I, Chaloupka, P, Chan, BK, Chang, F-H, Chang, Z, Chankova-Bunzarova, N, Chatterjee, A, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Csanád, M, Das, S, Dedovich, TG, Deppner, IM, Derevschikov, AA, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Dunlop, JC, Edmonds, T, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Y, Filip, P, Finch, E, Fisyak, Y, Fulek, L, Gagliardi, CA, Galatyuk, T, Geurts, F, Gibson, A, Gopal, K, Greiner, L, Grosnick, D, Gupta, A, Guryn, W, Hamad, AI, Hamed, A, Harris, JW, He, L, Heppelmann, S, Herrmann, N, Holub, L, Hong, Y, Horvat, S, Huang, B, Huang, HZ, and Huang, SL

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

We report the first measurement of rapidity-odd directed flow (v_{1}) for D^{0} and D^{0}[over ¯] mesons at midrapidity (|y|

Published
2019

8. Observation of Excess J/ψ Yield at Very Low Transverse Momenta in Au+Au Collisions at sNN=200 GeV and U+U Collisions at sNN=193 GeV

Author

Adam, J, Adamczyk, L, Adams, JR, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Arkhipkin, D, Aschenauer, EC, Ashraf, MU, Atetalla, F, Attri, A, Averichev, GS, Bairathi, V, Barish, K, Bassill, AJ, Behera, A, Bellwied, R, Bhasin, A, Bhati, AK, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Brandenburg, JD, Brandin, AV, Bryslawskyj, J, Bunzarov, I, Butterworth, J, Caines, H, Sánchez, M Calderón de la Barca, Cebra, D, Chakaberia, I, Chaloupka, P, Chan, BK, Chang, F-H, Chang, Z, Chankova-Bunzarova, N, Chatterjee, A, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Crawford, HJ, Csanad, M, Das, S, Dedovich, TG, Deppner, IM, Derevschikov, AA, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Dunlop, JC, Edmonds, T, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Y, Filip, P, Finch, E, Fisyak, Y, Fulek, L, Gagliardi, CA, Galatyuk, T, Geurts, F, Gibson, A, Grosnick, D, Gupta, A, Guryn, W, Hamad, AI, Hamed, A, Harris, JW, He, L, Heppelmann, S, Herrmann, N, Holub, L, Hong, Y, Horvat, S, Huang, B, Huang, HZ, Huang, SL, Huang, T, and Huang, X

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

We report on the first measurements of J/ψ production at very low transverse momentum (p_{T}

Published
2019

9. Polarization of Λ (Λ¯) Hyperons along the Beam Direction in Au+Au Collisions at sNN=200 GeV

Author

Adam, J, Adamczyk, L, Adams, JR, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Arkhipkin, D, Aschenauer, EC, Ashraf, MU, Atetalla, F, Attri, A, Averichev, GS, Bairathi, V, Barish, K, Bassill, AJ, Behera, A, Bellwied, R, Bhasin, A, Bhati, AK, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Brandenburg, JD, Brandin, AV, Bryslawskyj, J, Bunzarov, I, Butterworth, J, Caines, H, de la Barca Sánchez, M Calderón, Cebra, D, Chakaberia, I, Chaloupka, P, Chan, BK, Chang, F-H, Chang, Z, Chankova-Bunzarova, N, Chatterjee, A, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Crawford, HJ, Csanád, M, Das, S, Dedovich, TG, Deppner, IM, Derevschikov, AA, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Dunlop, JC, Edmonds, T, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Y, Filip, P, Finch, E, Fisyak, Y, Fulek, L, Gagliardi, CA, Galatyuk, T, Geurts, F, Gibson, A, Gopal, K, Grosnick, D, Gupta, A, Guryn, W, Hamad, AI, Hamed, A, Harris, JW, He, L, Heppelmann, S, Herrmann, N, Holub, L, Hong, Y, Horvat, S, Huang, B, Huang, HZ, Huang, SL, and Huang, T

Subjects
Nuclear and Plasma Physics, Physical Sciences, STAR Collaboration, nucl-ex, Mathematical Sciences, Engineering, General Physics, Mathematical sciences, Physical sciences
Abstract

The Λ (Λ[over ¯]) hyperon polarization along the beam direction has been measured in Au+Au collisions at sqrt[s_{NN}]=200  GeV, for the first time in heavy-ion collisions. The polarization dependence on the hyperons' emission angle relative to the elliptic flow plane exhibits a second harmonic sine modulation, indicating a quadrupole pattern of the vorticity component along the beam direction, expected due to elliptic flow. The polarization is found to increase in more peripheral collisions, and shows no strong transverse momentum (p_{T}) dependence at p_{T} greater than 1  GeV/c. The magnitude of the signal is about 5 times smaller than those predicted by hydrodynamic and multiphase transport models; the observed phase of the emission angle dependence is also opposite to these model predictions. In contrast, the kinematic vorticity calculations in the blast-wave model tuned to reproduce particle spectra, elliptic flow, and the azimuthal dependence of the Gaussian source radii measured with the Hanbury Brown-Twiss intensity interferometry technique reproduce well the modulation phase measured in the data and capture the centrality and transverse momentum dependence of the polarization signal.

Published
2019

10. Polarization of Λ (Λ[over ¯]) Hyperons along the Beam Direction in Au+Au Collisions at sqrt[s_{NN}]=200  GeV.

Author

Adam, J, Adamczyk, L, Adams, JR, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Arkhipkin, D, Aschenauer, EC, Ashraf, MU, Atetalla, F, Attri, A, Averichev, GS, Bairathi, V, Barish, K, Bassill, AJ, Behera, A, Bellwied, R, Bhasin, A, Bhati, AK, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Brandenburg, JD, Brandin, AV, Bryslawskyj, J, Bunzarov, I, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Cebra, D, Chakaberia, I, Chaloupka, P, Chan, BK, Chang, F-H, Chang, Z, Chankova-Bunzarova, N, Chatterjee, A, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Crawford, HJ, Csanád, M, Das, S, Dedovich, TG, Deppner, IM, Derevschikov, AA, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Dunlop, JC, Edmonds, T, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Y, Filip, P, Finch, E, Fisyak, Y, Fulek, L, Gagliardi, CA, Galatyuk, T, Geurts, F, Gibson, A, Gopal, K, Grosnick, D, Gupta, A, Guryn, W, Hamad, AI, Hamed, A, Harris, JW, He, L, Heppelmann, S, Herrmann, N, Holub, L, Hong, Y, Horvat, S, Huang, B, Huang, HZ, Huang, SL, and Huang, T

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

The Λ (Λ[over ¯]) hyperon polarization along the beam direction has been measured in Au+Au collisions at sqrt[s_{NN}]=200  GeV, for the first time in heavy-ion collisions. The polarization dependence on the hyperons' emission angle relative to the elliptic flow plane exhibits a second harmonic sine modulation, indicating a quadrupole pattern of the vorticity component along the beam direction, expected due to elliptic flow. The polarization is found to increase in more peripheral collisions, and shows no strong transverse momentum (p_{T}) dependence at p_{T} greater than 1  GeV/c. The magnitude of the signal is about 5 times smaller than those predicted by hydrodynamic and multiphase transport models; the observed phase of the emission angle dependence is also opposite to these model predictions. In contrast, the kinematic vorticity calculations in the blast-wave model tuned to reproduce particle spectra, elliptic flow, and the azimuthal dependence of the Gaussian source radii measured with the Hanbury Brown-Twiss intensity interferometry technique reproduce well the modulation phase measured in the data and capture the centrality and transverse momentum dependence of the polarization signal.

Published
2019

11. Azimuthal Harmonics in Small and Large Collision Systems at RHIC Top Energies

Author

Adam, J, Adamczyk, L, Adams, JR, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Arkhipkin, D, Aschenauer, EC, Ashraf, MU, Atetalla, F, Attri, A, Averichev, GS, Bai, X, Bairathi, V, Barish, K, Bassill, AJ, Behera, A, Bellwied, R, Bhasin, A, Bhati, AK, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Brandenburg, JD, Brandin, AV, Brown, D, Bryslawskyj, J, Bunzarov, I, Butterworth, J, Caines, H, de la Barca Sánchez, M Calderón, Cebra, D, Chakaberia, I, Chaloupka, P, Chan, BK, Chang, F-H, Chang, Z, Chankova-Bunzarova, N, Chatterjee, A, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Csanad, M, Das, S, Dedovich, TG, Deppner, IM, Derevschikov, AA, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Dunlop, JC, Efimov, LG, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Federicova, P, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Fulek, L, Gagliardi, CA, Galatyuk, T, Geurts, F, Gibson, A, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Guryn, W, Hamad, AI, Hamed, A, Harlenderova, A, Harris, JW, He, L, Heppelmann, S, and Herrmann, N

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

The first (v_{1}^{fluc}), second (v_{2}), and third (v_{3}) harmonic coefficients of the azimuthal particle distribution at midrapidity are extracted for charged hadrons and studied as a function of transverse momentum (p_{T}) and mean charged particle multiplicity density ⟨N_{ch}⟩ in U+U (sqrt[s_{NN}]=193  GeV), Au+Au, Cu+Au, Cu+Cu, d+Au, and p+Au collisions at sqrt[s_{NN}]=200  GeV with the STAR detector. For the same ⟨N_{ch}⟩, the v_{1}^{fluc} and v_{3} coefficients are observed to be independent of the collision system, while v_{2} exhibits such a scaling only when normalized by the initial-state eccentricity (ϵ_{2}). The data also show that ln(v_{2}/ϵ_{2}) scales linearly with ⟨N_{ch}⟩^{-1/3}. These measurements provide insight into initial-geometry fluctuations and the role of viscous hydrodynamic attenuation on v_{n} from small to large collision systems.

Published
2019

12. Low-pT e+e- Pair Production in Au+Au Collisions at sNN=200 GeV and U+U Collisions at sNN=193 GeV at STAR

Author

Adam, J, Adamczyk, L, Adams, JR, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Ajitanand, NN, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Arkhipkin, D, Aschenauer, EC, Ashraf, MU, Atetalla, F, Attri, A, Averichev, GS, Bai, X, Bairathi, V, Barish, K, Bassill, AJ, Behera, A, Bellwied, R, Bhasin, A, Bhati, AK, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Brandenburg, JD, Brandin, AV, Brown, D, Bryslawskyj, J, Bunzarov, I, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Chakaberia, I, Chaloupka, P, Chang, F-H, Chang, Z, Chankova-Bunzarova, N, Chatterjee, A, Chattopadhyay, S, Chen, JH, Chen, X, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Das, S, Dedovich, TG, Deppner, IM, Derevschikov, AA, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Dunlop, JC, Efimov, LG, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Federicova, P, Fedorisin, J, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Fulek, L, Gagliardi, CA, Galatyuk, T, Geurts, F, Gibson, A, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Guryn, W, Hamad, AI, Hamed, A, Harlenderova, A, Harris, JW, He, L, Heppelmann, S, and Herrmann, N

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

We report first measurements of e^{+}e^{-} pair production in the mass region 0.4

Published
2018

13. Beam Energy Dependence of Jet-Quenching Effects in Au+Au Collisions at sNN=7.7, 11.5, 14.5, 19.6, 27, 39, and 62.4 GeV

Author

Adamczyk, L, Adams, JR, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Ajitanand, NN, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Arkhipkin, D, Aschenauer, EC, Ashraf, MU, Attri, A, Averichev, GS, Bai, X, Bairathi, V, Barish, K, Behera, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandenburg, JD, Brandin, AV, Brown, D, Bunzarov, I, Butterworth, J, Caines, H, de la Barca Sánchez, M Calderón, Campbell, JM, Cebra, D, Chakaberia, I, Chaloupka, P, Chang, Z, Chankova-Bunzarova, N, Chatterjee, A, 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, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Federicova, P, Fedorisin, J, Feng, Z, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Fujita, J, Fulek, L, Gagliardi, CA, Garand, D, Geurts, F, Gibson, A, Girard, M, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, S, Gupta, A, Guryn, W, Hamad, AI, Hamed, A, and Harlenderova, A

Subjects
Affordable and Clean Energy, STAR Collaboration, nucl-ex, hep-ex, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

We report measurements of the nuclear modification factor R_{CP} for charged hadrons as well as identified π^{+(-)}, K^{+(-)}, and p(p[over ¯]) for Au+Au collision energies of sqrt[s_{NN}]=7.7, 11.5, 14.5, 19.6, 27, 39, and 62.4 GeV. We observe a clear high-p_{T} net suppression in central collisions at 62.4 GeV for charged hadrons which evolves smoothly to a large net enhancement at lower energies. This trend is driven by the evolution of the pion spectra but is also very similar for the kaon spectra. While the magnitude of the proton R_{CP} at high p_{T} does depend on the collision energy, neither the proton nor the antiproton R_{CP} at high p_{T} exhibit net suppression at any energy. A study of how the binary collision-scaled high-p_{T} yield evolves with centrality reveals a nonmonotonic shape that is consistent with the idea that jet quenching is increasing faster than the combined phenomena that lead to enhancement.

Published
2018

14. Beam-Energy Dependence of Directed Flow of Λ, Λ¯, K±, Ks0, and ϕ in Au+Au Collisions

Author

Adamczyk, L, Adams, JR, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Ajitanand, NN, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Arkhipkin, D, Aschenauer, EC, Ashraf, MU, Attri, A, Averichev, GS, Bai, X, Bairathi, V, Barish, K, Behera, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandenburg, JD, Brandin, AV, Brown, D, Bunzarov, I, Butterworth, J, Caines, H, de la Barca Sánchez, M Calderón, Campbell, JM, Cebra, D, Chakaberia, I, Chaloupka, P, Chang, Z, Chankova-Bunzarova, N, Chatterjee, A, Chattopadhyay, S, Chen, X, Chen, JH, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Das, S, De Silva, LC, Dedovich, TG, Deng, J, Derevschikov, AA, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Federicova, P, Fedorisin, J, Feng, Z, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Fujita, J, Fulek, L, Gagliardi, CA, Garand, D, Geurts, F, Gibson, A, Girard, M, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, Guryn, W, Hamad, AI, Hamed, A, Harlenderova, A, and Harris, JW

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

Rapidity-odd directed-flow measurements at midrapidity are presented for Λ, Λ[over ¯], K^{±}, K_{s}^{0}, and ϕ at sqrt[s_{NN}]=7.7, 11.5, 14.5, 19.6, 27, 39, 62.4, and 200 GeV in Au+Au collisions recorded by the Solenoidal Tracker detector at the Relativistic Heavy Ion Collider. These measurements greatly expand the scope of data available to constrain models with differing prescriptions for the equation of state of quantum chromodynamics. Results show good sensitivity for testing a picture where flow is assumed to be imposed before hadron formation and the observed particles are assumed to form via coalescence of constituent quarks. The pattern of departure from a coalescence-inspired sum rule can be a valuable new tool for probing the collision dynamics.

Published
2018

15. Beam-Energy Dependence of Directed Flow of Λ, Λ[over ¯], K^{±}, K_{s}^{0}, and ϕ in Au+Au Collisions.

Author

Adamczyk, L, Adams, JR, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Ajitanand, NN, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Arkhipkin, D, Aschenauer, EC, Ashraf, MU, Attri, A, Averichev, GS, Bai, X, Bairathi, V, Barish, K, Behera, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandenburg, JD, Brandin, AV, Brown, D, Bunzarov, I, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Chakaberia, I, Chaloupka, P, Chang, Z, Chankova-Bunzarova, N, Chatterjee, A, Chattopadhyay, S, Chen, X, Chen, JH, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Das, S, De Silva, LC, Dedovich, TG, Deng, J, Derevschikov, AA, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Federicova, P, Fedorisin, J, Feng, Z, Filip, P, Finch, E, Fisyak, Y, Flores, CE, Fujita, J, Fulek, L, Gagliardi, CA, Garand, D, Geurts, F, Gibson, A, Girard, M, Grosnick, D, Gunarathne, DS, Guo, Y, Gupta, A, Gupta, S, Guryn, W, Hamad, AI, Hamed, A, Harlenderova, A, and Harris, JW

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

Rapidity-odd directed-flow measurements at midrapidity are presented for Λ, Λ[over ¯], K^{±}, K_{s}^{0}, and ϕ at sqrt[s_{NN}]=7.7, 11.5, 14.5, 19.6, 27, 39, 62.4, and 200 GeV in Au+Au collisions recorded by the Solenoidal Tracker detector at the Relativistic Heavy Ion Collider. These measurements greatly expand the scope of data available to constrain models with differing prescriptions for the equation of state of quantum chromodynamics. Results show good sensitivity for testing a picture where flow is assumed to be imposed before hadron formation and the observed particles are assumed to form via coalescence of constituent quarks. The pattern of departure from a coalescence-inspired sum rule can be a valuable new tool for probing the collision dynamics.

Published
2018

16. Real-Space Imaging of the Tailored Plasmons in Twisted Bilayer Graphene

Author

Hu, F, Das, Suprem R, Luan, Y, Chung, T-F, Chen, YP, and Fei, Z

Subjects
Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

We report a systematic plasmonic study of twisted bilayer graphene (TBLG)-two graphene layers stacked with a twist angle. Through real-space nanoimaging of TBLG single crystals with a wide distribution of twist angles, we find that TBLG supports confined infrared plasmons that are sensitively dependent on the twist angle. At small twist angles, TBLG has a plasmon wavelength comparable to that of single-layer graphene. At larger twist angles, the plasmon wavelength of TBLG increases significantly with apparently lower damping. Further analysis and modeling indicate that the observed twist-angle dependence of TBLG plasmons in the Dirac linear regime is mainly due to the Fermi-velocity renormalization, a direct consequence of interlayer electronic coupling. Our work unveils the tailored plasmonic characteristics of TBLG and deepens our understanding of the intriguing nano-optical physics in novel van der Waals coupled two-dimensional materials.

Published
2017

20. Dijet imbalance measurements in Au+Au and pp collisions at sqrt[s_{NN}]=200  GeV at STAR.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Arkhipkin, D, Aschenauer, EC, Ashraf, MU, Attri, A, Averichev, GS, Bai, X, Bairathi, V, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandenburg, JD, Brandin, AV, Brown, D, Bunzarov, I, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Chakaberia, I, Chaloupka, P, Chang, Z, Chatterjee, A, 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, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Du, CM, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Z, Filip, P, Finch, E, 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, A, Gupta, S, Guryn, W, Hamad, AI, Hamed, A, Haque, R, Harris, JW, He, L, Heppelmann, S, Hirsch, A, and Hoffmann, GW

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

We report the first dijet transverse momentum asymmetry measurements from Au+Au and pp collisions at RHIC. The two highest-energy back-to-back jets reconstructed from fragments with transverse momenta above 2  GeV/c display a significantly higher momentum imbalance in heavy-ion collisions than in the pp reference. When reexamined with correlated soft particles included, we observe that these dijets then exhibit a unique new feature-momentum balance is restored to that observed in pp for a jet resolution parameter of R=0.4, while rebalancing is not attained with a smaller value of R=0.2.

Published
2017

21. Measurement of D0 Azimuthal Anisotropy at Midrapidity in Au+Au Collisions at sNN=200 GeV

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Ajitanand, NN, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Arkhipkin, D, Aschenauer, EC, Ashraf, MU, Attri, A, Averichev, GS, Bai, X, Bairathi, V, Behera, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandenburg, JD, Brandin, AV, Brown, D, Bunzarov, I, Butterworth, J, Caines, H, de la Barca Sánchez, M Calderón, Campbell, JM, Cebra, D, Chakaberia, I, Chaloupka, P, Chang, Z, Chankova-Bunzarova, N, Chatterjee, A, Chattopadhyay, S, Chen, X, Chen, JH, Cheng, J, Cherney, M, Christie, W, Contin, G, Crawford, HJ, Das, S, De Silva, LC, Debbe, RR, Dedovich, TG, Deng, J, Derevschikov, AA, Didenko, L, Dilks, C, Dong, X, Drachenberg, JL, Draper, JE, Dunkelberger, LE, Dunlop, JC, Efimov, LG, Elsey, N, Engelage, J, Eppley, G, Esha, R, Esumi, S, Evdokimov, O, Ewigleben, J, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Federicova, P, Fedorisin, J, Feng, Z, Filip, P, Finch, E, 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, A, Gupta, S, Guryn, W, Hamad, AI, Hamed, A, Harlenderova, A, Harris, JW, and He, L

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

We report the first measurement of the elliptic anisotropy (v_{2}) of the charm meson D^{0} at midrapidity (|y|

Published
2017

22. Charge-Dependent Directed Flow in Cu+Au Collisions at sNN=200 GeV

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Anderson, DM, Aoyama, R, Aparin, A, Arkhipkin, D, Aschenauer, EC, Ashraf, MU, Attri, A, Averichev, GS, Bai, X, Bairathi, V, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandenburg, JD, Brandin, AV, Bunzarov, I, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Chakaberia, I, Chaloupka, P, Chang, Z, Chatterjee, A, Chattopadhyay, S, Chen, X, Chen, JH, 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, Esumi, S, Evdokimov, O, Eyser, O, Fatemi, R, Fazio, S, Federic, P, Fedorisin, J, Feng, Z, Filip, P, Finch, E, 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, AI, Hamed, A, Haque, R, Harris, JW, He, L, Heppelmann, S, Hirsch, A, Hoffmann, GW, Horvat, S, and Huang, B

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

We present the first measurement of charge-dependent directed flow in Cu+Au collisions at sqrt[s_{NN}]=200  GeV. The results are presented as a function of the particle transverse momentum and pseudorapidity for different centralities. A finite difference between the directed flow of positive and negative charged particles is observed that qualitatively agrees with the expectations from the effects of the initial strong electric field between two colliding ions with different nuclear charges. The measured difference in directed flow is much smaller than that obtained from the parton-hadron-string-dynamics model, which suggests that most of the electric charges, i.e., quarks and antiquarks, have not yet been created during the lifetime of the strong electric field, which is of the order of, or less than, 1  fm/c.

Published
2017

28. Measurement of the Transverse Single-Spin Asymmetry in p↑+p→W±/Z0 at RHIC

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Aparin, A, Arkhipkin, D, Aschenauer, EC, Attri, A, Averichev, GS, Bai, X, Bairathi, V, Banerjee, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandenburg, JD, Brandin, AV, Bunzarov, I, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Chakaberia, I, Chaloupka, P, Chang, Z, Chattopadhyay, S, Chen, X, Chen, JH, 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, A, Gupta, S, Guryn, W, Hamad, A, Hamed, A, Haque, R, Harris, JW, He, L, Heppelmann, S, Hirsch, A, Hoffmann, GW, Hofman, DJ, Horvat, S, Huang, X, Huang, HZ, Huang, B, Huang, T, and Huck, P

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

We present the measurement of the transverse single-spin asymmetry of weak boson production in transversely polarized proton-proton collisions at sqrt[s]=500  GeV by the STAR experiment at RHIC. The measured observable is sensitive to the Sivers function, one of the transverse-momentum-dependent parton distribution functions, which is predicted to have the opposite sign in proton-proton collisions from that observed in deep inelastic lepton-proton scattering. These data provide the first experimental investigation of the nonuniversality of the Sivers function, fundamental to our understanding of QCD.

Published
2016

29. Beam Energy Dependence of the Third Harmonic of Azimuthal Correlations in Au+Au Collisions at RHIC

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Aparin, A, Arkhipkin, D, Aschenauer, EC, Attri, A, Averichev, GS, Bai, X, Bairathi, V, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandenburg, JD, Brandin, AV, Bunzarov, I, Butterworth, J, Caines, H, Calderón de la Barca Sánchez, M, Campbell, JM, Cebra, D, Chakaberia, I, Chaloupka, P, Chang, Z, Chatterjee, A, 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, AI, Hamed, A, Haque, R, Harris, JW, He, L, Heppelmann, S, Hirsch, A, Hoffmann, GW, Horvat, S, Huang, T, Huang, X, Huang, B, Huang, HZ, Huck, P, and Humanic, TJ

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

We present results from a harmonic decomposition of two-particle azimuthal correlations measured with the STAR detector in Au+Au collisions for energies ranging from sqrt[s_{NN}]=7.7 to 200 GeV. The third harmonic v_{3}^{2}{2}=⟨cos3(ϕ_{1}-ϕ_{2})⟩, where ϕ_{1}-ϕ_{2} is the angular difference in azimuth, is studied as a function of the pseudorapidity difference between particle pairs Δη=η_{1}-η_{2}. Nonzero v_{3}^{2}{2} is directly related to the previously observed large-Δη narrow-Δϕ ridge correlations and has been shown in models to be sensitive to the existence of a low viscosity quark gluon plasma phase. For sufficiently central collisions, v_{3}^{2}{2} persist down to an energy of 7.7 GeV, suggesting that quark gluon plasma may be created even in these low energy collisions. In peripheral collisions at these low energies, however, v_{3}^{2}{2} is consistent with zero. When scaled by the pseudorapidity density of charged-particle multiplicity per participating nucleon pair, v_{3}^{2}{2} for central collisions shows a minimum near sqrt[s_{NN}]=20  GeV.

Published
2016

30. Centrality and Transverse Momentum Dependence of Elliptic Flow of Multistrange Hadrons and ϕ Meson in Au+Au Collisions at sNN=200 GeV

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Bairathi, V, Banerjee, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandin, AV, Bunzarov, I, 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, X, Huang, B, Huang, HZ, Huck, P, Humanic, TJ, Igo, G, and Jacobs, WW

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

We present high precision measurements of elliptic flow near midrapidity (|y|

Published
2016

31. Centrality and Transverse Momentum Dependence of Elliptic Flow of Multistrange Hadrons and ϕ Meson in Au+Au Collisions at √[sNN]=200  GeV.

Author

Adamczyk, L, Adkins, JK, Agakishiev, G, Aggarwal, MM, Ahammed, Z, Alekseev, I, Aparin, A, Arkhipkin, D, Aschenauer, EC, Averichev, GS, Bairathi, V, Banerjee, A, Bellwied, R, Bhasin, A, Bhati, AK, Bhattarai, P, Bielcik, J, Bielcikova, J, Bland, LC, Bordyuzhin, IG, Bouchet, J, Brandin, AV, Bunzarov, I, 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, X, Huang, B, Huang, HZ, Huck, P, Humanic, TJ, Igo, G, and Jacobs, WW

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

We present high precision measurements of elliptic flow near midrapidity (|y|

Published
2016

32. 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

33. 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

34. 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

35. 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

36. 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

37. 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

39. 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

40. 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

41. 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

42. Lattice Strain Accompanying the Colossal Magnetoresistance Effect in EuB6

Author

Manna, Rudra Sekhar, Das, Pintu, de Souza, Mariano, Schnelle, Frank, Lang, Michael, Müller, Jens, von Molnár, Stephan, and Fisk, Zachary

Subjects
Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

The coupling of magnetic and electronic degrees of freedom to the crystal lattice in the ferromagnetic semimetal EuB(6), which exhibits a complex ferromagnetic order and a colossal magnetoresistance effect, is studied by high-resolution thermal expansion and magnetostriction experiments. EuB(6) may be viewed as a model system, where pure magnetism-tuned transport and the response of the crystal lattice can be studied in a comparatively simple environment, i.e., not influenced by strong crystal-electric field effects and Jahn-Teller distortions. We find a very large lattice response, quantified by (i) the magnetic Grüneisen parameter, (ii) the spontaneous strain when entering the ferromagnetic region, and (iii) the magnetostriction in the paramagnetic temperature regime. Our analysis reveals that a significant part of the lattice effects originates in the magnetically driven delocalization of charge carriers, consistent with the scenario of percolating magnetic polarons. A strong effect of the formation and dynamics of local magnetic clusters on the lattice parameters is suggested to be a general feature of colossal magnetoresistance materials.

Published
2014

43. 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

44. 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

45. 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

46. 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

47. 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

48. 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

49. 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

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