论文标题
治愈NLO Quarkonium在LHC处的非物理行为及其相关性，以限制低尺度的Gluon PDF
Curing the unphysical behaviour of NLO quarkonium production at the LHC and its relevance to constrain the gluon PDF at low scales
论文作者
论文摘要
我们解决了alpha_s中近代领先顺序（NLO）的Quarkonium-Hadrodulation横截面的非物理能量依赖性，我们将其归因于MSBAR方案中PDFS内部奇异性的分数过度缩写。在粒子物理学中的大多数散射过程中，这种过度提取的现象学相关性具有有限的现象学相关性。相反，它对P_T综合炭构造尤其有害，这使得一类广泛的NLO结果基本上是无法使用的。实际上，在这样的过程中，Alpha并不小，PDF的进化并不多，对于相应的动量分数而言可能相当平坦，最后，某些与过程相关的NLO碎片太小或太大。我们提出了一个固定标准，该标准避免了这样的过度填充。我们证明了它对ETA（C，B）的效率，也证明了虚拟光基本标量玻色子的效率。在提供了ETA（C，B）P_T综合横截面的稳定NLO预测之后，Sigma^nlo（Eta（Q）），并讨论了研究ETA（B）HADRRODOFURTUCT的选项，我们认为LHC在LHC上的测量值为LHC可以更好地确定lhc的lhc lhc pdf losimient in low scormient of low sconsity in of low sconsimpor的losimpody的00上的数量很高。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。。 GEV是身体与否。
We address the unphysical energy dependence of quarkonium-hadroproduction cross sections at Next-to-Leading Order (NLO) in alpha_S which we attribute to an over-subtraction in the factorisation of the collinear singularities inside the PDFs in the MSbar scheme. Such over- or under-subtractions have a limited phenomenological relevance in most of the scattering processes in particle physics. On the contrary, it is particularly harmful for P_T-integrated charmonium hadroproduction which renders a wide class of NLO results essentially unusable. Indeed, in such processes, alphaS is not so small, the PDFs are not evolved much and can be rather flat for the corresponding momentum fractions and, finally, some process-dependent NLO pieces are either too small or too large. We propose a scale-fixing criterion which avoids such an over-subtraction. We demonstrate its efficiency for eta(c,b) but also for a fictitious light elementary scalar boson. Having provided stable NLO predictions for eta(c,b) P_T-integrated cross sections, sigma^NLO(eta(Q)), and discussed the options to study eta(b) hadroproduction, we argue that their measurement at the LHC can help better determine the gluon PDF at low scales and tell whether the local minimum in conventional NLO gluon PDFs around x=0.001 at scales below 2 GeV is physical or not.
