Higher Orders in the Colour - Octet Model of J / ψ Production

نویسنده

  • Sourendu Gupta
چکیده

We study the hadro-and photo-production of ¯ cc and ¯ 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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تاریخ انتشار 1997