Color - Octet ψ ′ Production at Low p ⊥
نویسندگان
چکیده
We study contributions from color-octet quarkonium formation mechanisms to p ⊥-integrated ψ ′ production cross sections in pion-nucleon reactions. The observed polarization of the ψ ′ is not reproduced by the lowest-order leading-twist color-singlet and color-octet mechanisms. This suggests that there are important quarkonium production mechanisms beyond leading twist.
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تاریخ انتشار 1995