Vector-meson electroproduction at small Bjorken-x and generalized parton distributions
Vector-meson electroproduction at small Bjorken-x and generalized parton distributions
复制标题
小 Bjorken-x 和广义部分子分布下的矢量介子电产生
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
P. Kroll
中科院分区：
文献类型：
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作者：
S. Goloskokov;P. Kroll
我们用一种包括胶子广义部分子分布和部分子子过程的方法分析了小Bjorken-x上的轻矢量介子($V=Rho，Phi)的电产生，它包括一个部分子子过程，即$伽马gto(q{q})g$，$q{q}to V$。子过程被计算到微扰QCD的最低阶，同时考虑了夸克和反夸克的横向动量以及苏达科夫压抑。我们的方法允许我们研究各种极化虚光子和极化矢量介子的跃迁幅度。用双分布对广义部分子分布建模，用简单的高斯波函数描述矢量介子，计算了大光子虚线的纵横截面以及矢量介子的自旋密度矩阵元。我们的结果与最近在HERA进行的实验结果相当一致。
Abstract.We analyze electroproduction of light vector mesons ($V = \rho, \phi$) at small Bjorken-x in an approach that includes the gluonic generalized parton distributions and a partonic subprocess, $\gamma g \to (q\bar{q}) g$, $q\bar{q}\to V$. The subprocess is calculated to lowest order of perturbative QCD taking into account the transverse momenta of the quark and antiquark as well as Sudakov suppressions. Our approach allows us to investigate the transition amplitudes for all kinds of polarized virtual photons and polarized vector mesons. Modeling the generalized parton distributions through double distributions and using simple Gaussian wavefunctions for the vector mesons, we compute the longitudinal and transverse cross sections at large photon virtualities as well as the spin-density matrix elements for the vector mesons. Our results are in fair agreement with the findings of recent experiments performed at HERA.