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arXiv · hep-ph/9703370

Higher Orders in the Colour-Octet Model of J/ψProduction

Sourendu Gupta·Prakash Mathews
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Abstract

We study the hadro- and photo-production of $\bar cc$ and $\bar bb$ mesons at low transverse momentum to high orders in the relative velocity of the pair, v, in non-relativistic QCD. We evaluate cross sections to order v^7 for $η_c$, sufficient for studies of photo-production in the almost-elastic region. For all other charmonium states we find the cross section to order v^9, sufficient for studies of the ratio of $χ_{c1}$ and $χ_{c2}$ production rates. We find recurrence formulae for generating terms at even higher orders, should they be needed.

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Sourendu Gupta, Prakash Mathews. 1997-03-20. Higher Orders in the Colour-Octet Model of J/ψProduction. https://doi.org/10.1103/physrevd.56.3019

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