QCD corrections to polarization of J/{psi} and {upsilon} at Fermilab Tevatron and CERN LHC

Journal Article · Wed Oct 01 04:00:00 EDT 2008 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.78.074011· OSTI ID:21254280

Bin, Gong; Jianxiong, Wang ^[1]

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1. Institute of High Energy Physics, Chinese Academy of Sciences, P.O. Box 918(4), Beijing, 100049 (China) and Theoretical Physics Center for Science Facilities, Beijing, 100049 (China)

In this work, we present more details of the calculation on the next-to-leading-order (NLO) QCD corrections to polarization of direct J/{psi} production via color singlet at the Tevatron and LHC, together with the results for {upsilon} for the first time. Our results show that the J/{psi} polarization status drastically changes from transverse polarization dominant at leading order into longitudinal polarization dominant in the whole range of the transverse momentum p{sub t} of J/{psi} when the NLO corrections are counted. For {upsilon} production, the p{sub t} distribution of the polarization status behaves almost the same as that for J/{psi} except that the NLO result is transverse polarization at small p{sub t} range. Although the theoretical evaluation predicts a larger longitudinal polarization than the measured value at the Tevatron, it may provide a solution towards the previous large discrepancy for J/{psi} and {upsilon} polarization between theoretical prediction and experimental measurement, and suggests that the next important step is to calculate the NLO corrections to hadronproduction of color-octet state J/{psi}{sup (8)} and {upsilon}{sup (8)}. Our calculations are performed in two ways: namely, we do and do not analytically sum over the polarizations, and then check them with each other.

• OSTI ID: 21254280
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 7 Vol. 78; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CERN LHC
COLOR MODEL
CORRECTIONS
DISTRIBUTION
FERMILAB TEVATRON
FORECASTING
J PSI-3097 MESONS
MATHEMATICAL SOLUTIONS
POLARIZATION
QUANTUM CHROMODYNAMICS
TRANSVERSE MOMENTUM