Quarkonium production and NRQCD matrix elements
نویسنده
چکیده
One would hope, therefore, that it would be possible to calculate reliably in perturbation theory. If that were the end of the story, things would be simple. The only difficulty, which makes quarkonium very interesting, is that there is another natural small scale in the problem, the relative velocity of the heavy quarks, v. For charmonium v c ∼ 1/4, while for bottomonium v 2 b ∼ 1/10. Since we have a multi-scale problem, with the hierarchy
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تاریخ انتشار 2000