Two-photon annihilation into baryon-antibaryon pairs

被引：0

作者：

M. Diehl

P. Kroll

C. Vogt

机构：

[1] Institut für Theoretische Physik E,

[2] RWTH Aachen,undefined

[3] 52056 Aachen,undefined

[4] Germany ,undefined

[5] Fachbereich Physik,undefined

[6] Universität Wuppertal,undefined

[7] 42097 Wuppertal,undefined

[8] Germany ,undefined

[9] Nordita,undefined

[10] Blegdamsvej 17,undefined

[11] 2100 Copenhagen,undefined

[12] Denmark ,undefined

来源：

The European Physical Journal C - Particles and Fields | 2003年 / 26卷

关键词：

Experimental Data; Form Factor; Characteristic Feature; Momentum Transfer; Large Energy;

D O I：

暂无

中图分类号：

学科分类号：

摘要：

We study the handbag contribution to two-photon annihilation into baryon-antibaryon pairs at large energy and momentum transfer. We derive factorization of the process amplitude into a hard \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\gamma\gamma \to q\overline{q}$\end{document} subprocess and form factors describing the soft \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$q\overline{q}\to B\overline{B}$\end{document} transition, assuming that the process is dominated by configurations where the (anti)quark approximately carries the full momentum of the (anti)baryon. The form factors represent moments of time-like generalized parton distributions, so-called \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$B\overline{B}$\end{document} distribution amplitudes. A characteristic feature of the handbag mechanism is the absence of isospin-two components in the final state, which in combination with flavor symmetry provides relations among the form factors for the members of the lowest-lying baryon octet. Assuming dominance of the handbag contribution, we can describe current experimental data with form factors of plausible size, and predict the cross sections of presently unmeasured \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$B\overline{B}$\end{document} channels.

引用

页码：567 / 577

页数：10