Recent results on nucleon spin structure study at RHIC

Abstract

Both the PHENIX and STAR experiments at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory are running polarized proton–proton collisions at \sqrt{s}= 200 and 500 GeV. The main goal of the RHIC spin physics program is to gain deeper insight into the spin structure of the nucleon. We will give an overview of recent spin results from RHIC, particularly the study of gluon polarization via jet/hadron production and sea quark polarization via W boson production in longitudinally polarized proton–proton collisions.

Keywords

RHIC / nucleon spin structure / gluon polarization / sea quark polarization

References

[1] For a review, see, e.g.,C. A. Aidala, S. D. Bass, D. Hasch, and G. K. Mallot, The spin structure of the nucleon, Rev. Mod. Phys. 85, 655 (2013), arXiv: 1209.2803 [hep-ph]

[2] G. Bunce, N. Saito, J. Soffer, and W. Vogelsang, Prospects for spin physics at RHIC, Annu. Rev. Nucl. Part. Sci. 50, 525 (2000), arXiv: hep-ph/0007218

[3] D.de Florian and W. Vogelsang, Resummed cross-section for jet production at hadron colliders, Phys. Rev. D 76, 074031 (2007), arXiv: 0704.1677 [hep-ph]

[4] A. Mukherjee and W. Vogelsang, Jet production in (un)polarized pp collisions: Dependence on jet algorithm, Phys. Rev. D 86, 094009 (2012), arXiv: 1209.1785 [hep-ph]

[5] E. C. Aschenauer, et al., The RHIC SPIN program: Achievements and future opportunities, arXiv: 1501.01220 [nucl-ex]

[6] J. Blümlein and H. Böttcher, QCD analysis of polarized deep inelastic scattering data, Nucl. Phys. B 841, 205 (2010), arXiv: 1005.3113

[7] D. de Florian, R. Sassot, M. Stratmann, and W. Vogelsang, Global analysis of helicity Parton densities and their uncertainties, Phys. Rev. Lett. 101, 072001 (2008), arXiv: 0804.0422 [hep-ph]

[8] D. de Florian, R. Sassot, M. Stratmann, and W. Vogelsang, Extraction of spin-dependent Parton densities and their uncertainties, Phys. Rev. D 80, 034030 (2009), arXiv: 0904.3821

[9] E. Leader, A. V. Sidorov, and D. B. Stamenov, Determination of polarized PDFs from a QCD analysis of inclusive and semi-inclusive deep inelastic scattering data, Phys. Rev. D 82, 114018 (2010), arXiv: 1010.0574

[10] R. D. Ball, et al. (NNPDF Collaboration), Unbiased determination of polarized parton distributions and their uncertainties, Nucl. Phys. B 874, 36 (2013), arXiv: 1303.7236

[11] G. C. Blazey, J. R. Dittmann, S. D. Ellis, V. D. Elvira, K. Frame, S. Grinstein, R. Hirosky, R. Piegaia, H. Schellman, R. Snihur, V. Sorin, and D. Zeppenfeld, Run II jet physics: Proceedings of the Run II QCD and Weak Boson Physics Workshop, arXiv: hep-ex/0005012

[12] M. Cacciari, G. P. Salam, and G. Soyez, The anti-k(t) jet clustering algorithm, JHEP 0804, 063 (2008) , arXiv: 0802.1189 [hep-ph]

[13] B. I. Abelev, et al. (STAR Collaboration), Longitudinal double-spin asymmetry and cross section for inclusive jet production in polarized proton collisions at s= 200 GeV, Phys. Rev. Lett. 97, 252001 (2006)

[14] B. I. Abelev, et al. (STAR Collaboration), Longitudinal double-spin asymmetry for inclusive jet production in p+p collisions at s= 200 GeV, Phys. Rev. Lett. 100, 232003 (2008)

[15] L. Adamczyk, et al. (STAR Collaboration), Longitudinal and transverse spin asymmetries for inclusive jet production at mid-rapidity in polarized p+p collisions at NNs=200 GeV, Phys. Rev. D 86, 032006 (2012)

[16] B. I. Abelev, et al. (STAR Collaboration), Longitudinal double-spin asymmetry and cross section for inclusive neutral pion production at midrapidity in polarized proton collisions at NNs=200 GeV, Phys. Rev. D 80, 111108 (2009)

[17] L. Adamczyk, et al. (STAR Collaboration), Neutral pion cross section and spin asymmetries at intermediate pseudorapidity in polarized proton collisions at s= 200 GeV, Phys. Rev. D 89, 012001 (2014), arXiv: 1309.1800 [nucl-ex]

[18] L. Adamczyk, et al. (STAR Collaboration), Precision measurement of the longitudinal double-spin asymmetry for inclusive jet production in polarized proton collisions at s=200 GeV, arXiv: 1405.5134 [hep-ex]

[19] E. R. Nocera, et al. (NNPDF Collaboration), A first unbiased global determination of polarized PDFs and their uncertainties, Nucl. Phys. B 887, 276 (2014), arXiv: 1406.5539 [hep-ph]

[20] A. Adare, et al. (PHENIX Collaboration), Inclusive double-helicity asymmetries in neutral-pion and eta-meson production in p+p collisions at s=200 GeV, Phys. Rev. D 90, 012007 (2014), arXiv: 1402.6296 [hep-ex]

[21] D. de Florian, R. Sassot, M. Stratmann, and W. Vogelsang, Evidence for polarization of gluons in the proton, Phys. Rev. Lett. 113, 012001 (2014), arXiv: 1404.4293 [hep-ph]

[22] W. C. Chang and J. C. Peng, Flavor structure of the nucleon sea, Prog. Part. Nucl. Phys. 79, 95 (2014) arXiv: 1406.1260 [hep-ph]

[23] M. Aggarwal, et al. (STAR Collaboration), Measurement of the parity-violating longitudinal single-spin asymmetry for W^± boson production in polarized proton-proton collisions at s=500 GeV, Phys. Rev. Lett. 106, 062002 (2011), arXiv: 1009.0326

[24] A. Adare, et al. (PHENIX Collaboration), Cross section and parity-violating spin asymmetries of W^± boson production in polarized p+p collisions at s=500 GeV, Phys. Rev. Lett. 106, 062001 (2011)

[25] L. Adamczyk, et al. (STAR Collaboration), Measurement of the W→eν and Z/γ*→e+e− production cross sections at mid-rapidity in proton-proton collisions at s=500 GeV, Phys. Rev. D 85, 092010 (2012)

[26] L. Adamczyk, et al. (STAR Collaboration), Measurement of longitudinal spin asymmetries for weak boson production in polarized proton-proton collisions at RHIC, Phys. Rev. Lett. 113, 072301 (2014), arXiv: 1404.6880 [nucl-ex]

[27] D. de Florian and W. Vogelsang, Helicity parton distributions from spin asymmetries in W-boson production at RHIC, Phys. Rev. D 81, 094020 (2010)

[28] P. M. Nadolsky and C. P. Yuan, Single-spin physics with weak bosons at RHIC, Nucl. Phys. B 666(1), 31 (2003)

[29] E. C. Aschenauer, A.Bazilevsky, K. Boyle, K. O. Eyser, R. Fatemi, C. Gagliardi, M. Grosse-Perdekamp, J. Lajoie, ZhongboKang, Y. Kovchegov, et al., The RHIC spin program: Achievements and future opportunities, arXiv: 1304.0079

[30] A. Adare, et al. (PHENIX Collaboration), Measurement of parity-violating spin asymmetries in W^� production at midrapidity in longitudinally polarized p+p collisions, arXiv: 1504.07451 [hep-ex]

[31] D. de Florian, M. Stratmann, and W. Vogelsang, Polarized Λ-baryon production in pp collisions, Phys. Rev. Lett. 81, 530 (1998)

[32] Q. H. Xu, Z. T. Liang, and E. Sichtermann, Transfer matrix with Kogut-Susskind fermions, Phys. Rev. D 73, 077503 (2006)

[33] B. I. Abelev, et al. (STAR Collaboration), Longitudinal spin transfer to Λ and Λ¯ hyperons in polarized proton-proton collisions at s= 200 GeV, Phys. Rev. D 80, 111102 (2009)

[34] J. Deng, et al. (STAR Collaboration), Longitudinal spin transfer to Λ and Λ¯ in polarized proton-proton collisions at s= 200 GeV at STAR, Physics of Particle and Nuclei 45(1), 73 (2014)

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg