高能电子-质子碰撞中重夸克偶素的遍举产生

doi:10.7523/j.issn.2095-6134.2019.06.002

摘要/Abstract

摘要： 夸克偶素产生和衰变研究对深入了解量子色动力学（QCD），研究夸克偶素，甚至探索其他高能相互作用和微观粒子的性质都具有重要意义。计算重夸克偶素在电子-质子高能碰撞中的遍举产生，发现它能为探究质子部分子的分布结构，验证非相对论量子色动力学，精确检验微扰QCD的适用范围提供有益的帮助。在共线因子化框架下，计算给出QCD领头阶重夸克偶素遍举产生的振幅和截面的解析结果，并以HERA实验为例，唯象分析HERA实验条件下J/ψ和Υ遍举产生截面随Q²和W_γp的变化规律，与实验结果进行比对。还讨论了能标和重夸克质量不确定性带来的理论分析误差。

关键词: 重夸克偶素, 遍举产生, 广义部分子分布函数, 非相对论量子色动力学

Abstract: Quarkonium production and decay play an important role in the investigations of quantum chromodynamics(QCD) and the properties of quarkonium and other high energy interactions and particles. In this work, we calculate the heavy quarkonium exclusive production in electron-proton scattering, and find that it may deepen our understanding of the parton structure of nucleon, testify the non-relativistic QCD(NRQCD) formalism, and specify the applicability scope of perturbative QCD(pQCD). Within the collinear factorization framework, we analytically calculate the amplitude and cross section of quarkonium exclusive production at the leading order of pQCD. Taking the HERA experiment of photoproduction and electroproduction as an example, we analyze phenomenologically the cross-section dependence of J/ψ and Υ production on Q² and W_γp. We estimate also the theoretical errors induced by the energy-scale and quark-mass uncertainties.

Key words: heavy quarkonium, exclusive production, GPDs, NRQCD

中图分类号:

O572.33

王晨, 陈自强, 乔从丰. 高能电子-质子碰撞中重夸克偶素的遍举产生[J]. 中国科学院大学学报, 2019, 36(6): 729-735.

WANG Chen, CHEN Ziqiang, QIAO Congfeng. Exclusive quarkonium production in high energy e-p collision[J]. , 2019, 36(6): 729-735.

参考文献

[1] Bodwin G T, Braaten E, Lepage G P. Rigorous QCD analysis of inclusive annihilation and production of heavy quarkonium[J]. Phys Rev D, 1995, 51(3):1 125-1 171.
[2] Quarkonium Working Group. Heavy quarkonium physics[G]. arXiv:hep-ph/0412158.
[3] Binkley M, Bohler C, Butler J, et al. J/ψ photoproduction from 60 to 300 GeV/c[J]. Phys Rev Lett, 1982, 48(2):73-76.
[4] Denby B H, Bharadwaj V K, Summers D J, et al. Inelastic and elastic photoproduction of J/ψ(3 097)[J]. Phys Rev Lett, 1984, 52(10):795-798.
[5] Breitweg J, Derrick M, Krakauer D, et al. Measurement of elastic Υ photoproduction at HERA[J]. Phys Lett B, 1998, 437(3/4):432-444.
[6] Adloff C, Andreev V, Andrieu B, et al. Elastic photoproduction of J/ψ and Υ mesons at HERA[J]. Phys Lett B, 2000, 483(1-3):23-35.
[7] Aid S, Andreev V, Andrieu B, et al. Elastiv and inelastic photoproduction of J/ψ mesons at HERA[J]. Nucl Phys B, 1996, 472(1/2):3-31.
[8] Breitweg J, Derrick M, Krakauer D, et al. Measurement of elastic J/ψ photoproduction at HERA[J]. Z Phys C, 1997, 75(2):215-228.
[9] Chekanov S, Krakauer D, Magill S, et al. Exclusive photoproduction of J/ψ mesons at HERA[J]. Eur Phys J C, 2002, 24(3):345-360.
[10] Aid S, Andreev V, Andrieu B, et al. Elastic electroproduction of ρ and J/ψ mesons at large Q² at HERA[J]. Nucl Phys B, 1996, 468(1/2):3-33.
[11] Breitweg J, Chekanov S, Derrick M, et al. Exclusive electroproduction of ρ⁰ and J/ψ mesons at HERA[J]. Eur Phys J C, 1999, 6(4):603-627.
[12] Chekanov S, Derrick M, Loizides J H, et al. Exclusive electroproduction of J/ψ mesons at HERA[J]. Nucl Phys B, 2004, 695(1/2):2-37.
[13] Aktas A, Andreev V, Anthonis T, et al. Elastic J/ψ production at HERA[J]. Eur Phys J C, 2006, 46(3):585-603.
[14] Aaij R, Beteta C A, Adametz A, et al. Exclusive J/ψ and ψ(2S) in pp collisions at √s=7 TeV[J]. J Phys G, 2013, 40(4):045 001.
[15] Aaij R, Adeva B, Adinolfi M, et al. Updated measurements of exclusive J/ψ and ψ(2S) production cross-sections in pp collisions at √s=7 TeV[J]. J Phys G, 2014, 41(5):055 002.
[16] Aaij R, Adeva B, Adinolfi M, et al. Measurement of the exclusive Υ production cross-section in pp collisions at √7 TeV and 8 TeV[J]. JHEP, 2015(9):84.
[17] Kuraev E A, Lipatov L N, Fadin V S. The pomeranchuk singularity in nonabelian gauge theories[J]. Sov Phys JETP, 1977, 45(2):199-204.
[18] Balitsky I I, Lipatov L N. The pomeranchuk singularity in quamtum chromodynamics[J]. Sov J Nucl Phys, 1978, 28:822-829.
[19] Ryskin M G. Diffractive J/ψ electroproduction in LLA QCD[J]. Z Phys C, 1993, 57(1):89-92.
[20] Frankfurt L, Koepf W, Strikman M. Hard diffractive electroproduction of vector mesons in QCD[J]. Phys Rev D, 1996, 54(5):3 194-3 215.
[21] Levin E M, Martin A D, Ryskin M G, et al. Diffractive open charm production at HERA[J]. Z Phys C, 1997, 74(4):671-685.
[22] Ryskin M G, Roberts R G, Martin A D, et al. Diffractive J/ψ photoproduction as a probe of the gluon density[J]. Z Phys C, 1997, 76(2):231-239.
[23] Martin A D, Ryskin M G, Teubner T. QCD description of diffractive ρ meson electroproduction[J]. Phys Rev D, 1997, 55(7):4 329-4 337.
[24] Hoodbhoy P. Wave function corrections and off-forward gluon distributions in diffractive J/ψ electroproduction[J]. Phys Rev D, 1997, 56(1):388-393.
[25] Martin A D, Ryskin M G, Teubner T. Q² dependence of diffractive vector meson electroproduction[J]. Phys Rev D, 2000, 62:014 002.
[26] Martin A D, Ryskin M G, Teubner T. Υ photoproduction at HERA compared to estimates of perturbative QCD[J]. Phys Lett B, 1999, 454(3/4):339-345.
[27] Martin A D, Nockles C, Ryskin M G, et al. Small x gluon from exculsive J/ψ production[J]. Phys Lett B, 2008, 662(3):252-258.
[28] Jones S P, Martin A D, Ryskin M G, et al. Probes of the small x gluon via exclusive J/ψ and Υ production at HERA and the LHC[J]. JHEP, 2013(11):85.
[29] Radyushkin A V. Scaling limit of deeply virtual compton scattering[J]. Phys Lett B, 1996, 380(2-4):417-425.
[30] JI Xiangdong. Gauge-Invariant decomposition of nucleon spin[J]. Phys Rev Lett, 1997, 78(4):610-613.
[31] JI Xiangdong. Deeply virtual Compton scattering[J]. Phys Rev D, 1997, 55(11):7 114-7 125.
[32] Radyushkin A V. Asymmetric gluon distributions and hard diffractive electroproduction[J]. Phys Lett B, 1996, 385Z(1-4):333-342.
[33] Collins J C, Frankfurt L, Strikman M. Factorization for hard exclusive electroproduction of mesons in QCD[J]. Phys Rev D, 1997, 56(5):2 982-3 006.
[34] Ivanov D Y, Schafer A, Szymanowski L, Krasnikov G. Exclusive photoproduction a heavy vector meson in QCD[J]. Eur Phys J C, 2004, 34(3):297-316.
[35] Ivanov D Y, Pire B, Szymanowski L, et al. Probing GPDs in ultraperipheral collisions[C]//AIP Conf Proc 2015, 1654:090 003.
[36] Jones S P, Martin A D, Ryskin M G, et al. Exclusive J/ψ and Υ photoproduction and the low x gluon[J]. J Phys G, 2016, 43(3):035 002.
[37] Jones S P, Martin A D, Ryskin M G, et al. The exclusive J/ψ process at the LHC tamed to probe the low x gluon[J]. Eur Phys J C, 2016, 76(11):633.
[38] Braaten E, Lee J. Exclusive double-charmonium production from esup>+e^- annihilation into a virtue photon[J]. Phys Rev D, 2003, 67:054 007.
[39] Diehl M. Generalized parton distributions[J]. Phys Rept, 2003, 388(2-4):41-277.
[40] Vanttinen M, Mankiewicz L. Hard exclusive J/ψ leptoproduction on polarized targets[J]. Phys Lett B, 1998, 434(1/2):141-146.
[41] Eichten E J, Quigg C. Quarkonium wave functions at the origin[J]. Phys Rev D, 1995, 52(3):1 726-1 728.
[42] Radyushkin A V. Double distributions and evolution equations[J]. Phys Rev D, 1999, 59:014030.
[43] Radyushkin A V. Symmetries and structure of skewed and double distributions[J]. Phys Lett B, 1999, 449(1/2):81-88.
[44] Freund A, McDermott M, Strikman M. Modeling generalized parton distributions to describe deeply virtual Compton scattering data[J]. Phys Rev D, 2003, 67:036 001.