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Cancellation of Infrared Divergence in Inclusive Production of Heavy Quarkonia
A scheme is presented here to cancel out the topologically unfactorized
infrared divergences in the inclusive production of heavy quarkonia, which
affect the NRQCD factorization of these processes. The heavy quarkonia are
defined as resonance states of QCD instead of color singlet heavy quark pair.
Thus the final heavy quark pair is nor necessarily to be color singlet. In
addition, the heavy quarkonia are reconstructed by their decay products. As the
result, transition between states containing containing heavy quarks caused by
exchanges of soft gluons are also taken into account here. Such cancellation is
crucial for the NRQCD factorization of these processes.Comment: 17 pages, 26 figure
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