Erratum: PolarizedJ/ψproduction in deep inelastic scattering at DESY HERA [Phys. Rev. D 63, 034017 (2001)]

Abstract

We perform a calculation on the polarization of J/ψ production in deep inelastic scattering in the HERA energy range. For the inclusive production distributions, we find that the color-singlet contributions are consistent with the experimental data in the major region of z (z > 0.4). Only in low z regions, there are some hints of the need of the color-octet contributions to describe the experimental data. For the polarization of J/ψ in DIS processes, we find the parameter α changes with Q 2 . Especially, at higher Q 2 , difference on α between color-singlet and color-octet contributions become more distinctive. In the two regions of lower and larger z, the polarization parameter α have different features. These properties can provide important information on the polarization mechanism for J/ψ production. PACS number(s): 12.40. Nn, 13.85.Ni, 14.40.Gx

J/ψ inclusive production in ep deep-inelastic scattering at DESY HERA

“…In Ref. [27], also cross section formulas for the CO partonic subprocesses e + a → e + cc[n] + a with a = g, q, q and n…”

“…Formulas for the cross section of the CS partonic subprocess e + g → e + cc + g may be found in Refs. [23,24,25,26,27]. In Ref.…”

“…Finally, the literature contains mutually inconsistent formulas for the cross section of the CS partonic subprocess e + g → e + cc + g [23,24,25,26,27]. On the other hand, there is only one paper specifying analytic results for the cross sections of the CO partonic subprocesses enumerated above [27], so that an independent check seems to be in order.…”

“…On the other hand, there is only one paper specifying analytic results for the cross sections of the CO partonic subprocesses enumerated above [27], so that an independent check seems to be in order. We anticipate that we disagree with all published CS and CO formulas, except with the one referring to e + g → e + cc…”

$J/\psi$ production at HERA in the color singlet model with $k_{\mathrm{T}}$ -factorization

“…Results obtained within the usual collinear approach and CS model [34][35][36][37] underestimate experimental data by factor about 2.…”