论文标题
Quarkonium的理论：从NRQCD分解到软gluon分解
Theory for quarkonium: from NRQCD factorization to soft gluon factorization
论文作者
论文摘要
我们证明，最近提出的软gluon分解（SGF）等同于重量产量或衰减的非同性QCD（NRQCD）分解，这意味着，对于任何给定的过程，这两个分解理论既有效又有效。我们使用两种方法来得出这一结论。在第一个方法中，我们将两个分解理论应用于物理过程$ j/ψ\ to e^+e^ - $。我们的明确计算表明，SGF和NRQCD都可以正确地重现完整QCD的低能量物理，因此两个因素化是等效的。在第二种方法中，通过使用运动方程，我们成功地从NRQCD有效场理论中推导了SGF。通过以NRQCD分解识别SGF，我们在两个分解理论之间建立了关系，并证明了广义的Gremm-Kapustin关系是乘积。与NRQCD分解相比，SGF的优势在于，它恢复了一系列相对论校正，源自对所有力量的运动效应，这在相对论扩张中产生了更好的收敛性。
We demonstrate that the recently proposed soft gluon factorization (SGF) is equivalent to the nonrelativistic QCD (NRQCD) factorization for heavy quarkonium production or decay, which means that for any given process these two factorization theories are either both valid or both violated. We use two methods to achieve this conclusion. In the first method, we apply the two factorization theories to the physical process $J/ψ\to e^+e^-$. Our explicit calculation shows that both SGF and NRQCD can correctly reproduce low energy physics of full QCD, and thus the two factorizations are equivalent. In the second method, by using equations of motion we successfully deduce SGF from NRQCD effective field theory. By identifying SGF with NRQCD factorization, we establish relations between the two factorization theories and prove the generalized Gremm-Kapustin relations as a by product. Comparing with the NRQCD factorization, the advantage of SGF is that it resums the series of relativistic corrections originated from kinematic effects to all powers, which gives rise to a better convergence in relativistic expansion.
