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Single Polarisation Asymmetries for Quarkonia in Non-relativistic QCD

Sourendu Gupta
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Abstract

We find that single spin asymmetries in NRQCD are non-vanishing in general. They are proportional to the imaginary parts of some non-perturbative matrix elements. With statistics of about 10^6 identified J/psi's, or 10^5 identified chi_2, it is possible to measure these imaginary parts even if they are an order of magnitude smaller than the real parts. Such statistics are quite reasonable at polarised HERA N and other future experiments.

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Sourendu Gupta. 1997-07-11. Single Polarisation Asymmetries for Quarkonia in Non-relativistic QCD. https://doi.org/10.1103/physrevd.57.1858

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