Relativistic corrections to J/{psi} exclusive and inclusive double charm production at B factories
Abstract
In order to clarify the puzzling problems in doublecharm production, relativistic corrections at order v{sup 2} to the processes e{sup +}e{sup }{yields}J/{psi}+{eta}{sub c} and e{sup +}e{sup }{yields}J/{psi}+cc at B factories are studied in nonrelativistic quantum chromodynamics. The shortdistance parts of production cross sections are calculated perturbatively, while the longdistance matrix elements are estimated from J/{psi} and {eta}{sub c} decays up to errors of order v{sup 4}. Our results show that the relativistic correction to the exclusive process e{sup +}e{sup }{yields}J/{psi}+{eta}{sub c} is significant, which, when combined together with the nexttoleadingorder {alpha}{sub s} corrections, could resolve the large discrepancy between theory and experiment; whereas for the inclusive process e{sup +}e{sup }{yields}J/{psi}+cc the relativistic correction is tiny and negligible. The physical reason for the above difference between exclusive and inclusive processes largely lies in the fact that in the exclusive process the relative momentum between quarks in charmonium substantially reduces the virtuality of the gluon that converts into a charm quark pair, but this is not the case for the inclusive process, in which the charm quark fragmentation c{yields}J/{psi}+c is significant, and QCD radiative corrections can be more essential.
 Authors:
 Department of Physics, Peking University, Beijing 100871 (China)
 (World Laboratory), Beijing 100080 (China)
 Publication Date:
 OSTI Identifier:
 21020271
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevD.75.074011; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CROSS SECTIONS; ELECTRONPOSITRON INTERACTIONS; ELECTRONS; ERRORS; ETA C2980 MESONS; GLUONS; J PSI3097 MESONS; MATRIX ELEMENTS; PARTICLE DECAY; POSITRONS; PSI3770 MESONS; QUANTUM CHROMODYNAMICS; QUARKS; RADIATIVE CORRECTIONS; RELATIVISTIC RANGE
Citation Formats
He Zhiguo, Fan Ying, Chao Kuangta, and China Center of Advanced Science and Technology. Relativistic corrections to J/{psi} exclusive and inclusive double charm production at B factories. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.074011.
He Zhiguo, Fan Ying, Chao Kuangta, & China Center of Advanced Science and Technology. Relativistic corrections to J/{psi} exclusive and inclusive double charm production at B factories. United States. doi:10.1103/PHYSREVD.75.074011.
He Zhiguo, Fan Ying, Chao Kuangta, and China Center of Advanced Science and Technology. Sun .
"Relativistic corrections to J/{psi} exclusive and inclusive double charm production at B factories". United States.
doi:10.1103/PHYSREVD.75.074011.
@article{osti_21020271,
title = {Relativistic corrections to J/{psi} exclusive and inclusive double charm production at B factories},
author = {He Zhiguo and Fan Ying and Chao Kuangta and China Center of Advanced Science and Technology},
abstractNote = {In order to clarify the puzzling problems in doublecharm production, relativistic corrections at order v{sup 2} to the processes e{sup +}e{sup }{yields}J/{psi}+{eta}{sub c} and e{sup +}e{sup }{yields}J/{psi}+cc at B factories are studied in nonrelativistic quantum chromodynamics. The shortdistance parts of production cross sections are calculated perturbatively, while the longdistance matrix elements are estimated from J/{psi} and {eta}{sub c} decays up to errors of order v{sup 4}. Our results show that the relativistic correction to the exclusive process e{sup +}e{sup }{yields}J/{psi}+{eta}{sub c} is significant, which, when combined together with the nexttoleadingorder {alpha}{sub s} corrections, could resolve the large discrepancy between theory and experiment; whereas for the inclusive process e{sup +}e{sup }{yields}J/{psi}+cc the relativistic correction is tiny and negligible. The physical reason for the above difference between exclusive and inclusive processes largely lies in the fact that in the exclusive process the relative momentum between quarks in charmonium substantially reduces the virtuality of the gluon that converts into a charm quark pair, but this is not the case for the inclusive process, in which the charm quark fragmentation c{yields}J/{psi}+c is significant, and QCD radiative corrections can be more essential.},
doi = {10.1103/PHYSREVD.75.074011},
journal = {Physical Review. D, Particles Fields},
number = 7,
volume = 75,
place = {United States},
year = {Sun Apr 01 00:00:00 EDT 2007},
month = {Sun Apr 01 00:00:00 EDT 2007}
}

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