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NRQCD: A Critical Review

Ira Z. Rothstein
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Abstract

In this talk I review some recent applications of NRQCD. I first discuss the unquenched NRQCD lattice extractions of the strong coupling constant, paying particular attention to the recent advances in reducing systematic errors. I then discuss the progress made in testing the NRQCD/factorization formalism for onium production. In particular, I gather the evidence, or lack thereof, for the universality of the production matrix elements. I also discuss the interesting question of polarized production, which is a crucial test of the formalism. I address the viability of this theory for the J/psi system as well as what needs to be done before we can reach any definitive conclusions.

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Ira Z. Rothstein. 1999-11-09. NRQCD: A Critical Review. https://arxiv.org/abs/hep-ph/9911276

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