It is very likely that hadronic scattering will enter a new regime at the LHC, as the black-disk limit is reached. This will lead to a severe change in the t dependence of the real part and of the slope of the elastic scattering amplitude, and in turn this may bias the measurement of the total cross section. We examine this issue, and suggest new strategies to test the reliability of the total cross section measurements.
We review the status of NNLO calculations for jet cross sections at the LHC. In particular, we describe how perturbative stability and convergence can be used as criteria to select the most appropriate scales in the theoretical description of di-jet and single jet inclusive production.
Next-To-Leading Order Differential Cross-Sections for $J/ψ$, $ψ(2S)$ and $Υ$ Production in Proton-Proton Collisions at a Fixed-Target Experiment using the LHC Beams (AFTER@LHC)
In the light of the latest data by LHCf collaboration of the LHC on leading neutrons spectra it is possible to obtain total pion-proton cross-sections in the TeV energy region. In this work the exact extraction procedure is shown. Final numbers for the pion-proton cross-section are collected at several different values of the colliding energy and compared with some popular theoretical predictions. Errors of results are estimated.
The measurement of the triple-differential dijet production cross section as a function of the average transverse momentum $p_{T,\textrm{avg}}$, half the rapidity separation $y^{*}$, and the boost $y_{b}$ of the two leading jets in the event enables a kinematical scan of the underlying parton momentum distributions. We compute for the first time the second-order perturbative QCD corrections to this triple-differential dijet cross section, at leading color in all partonic channels, thereby enabling precision studies with LHC dijet data. A detailed comparison with experimental CMS 8 TeV data is …
The effect of full $7$ sets of LHC ATLAS jet cross sections data at $ \sqrt{s} = 7$ TeV on the proton parton distribution functions (PDFs) up to next-to-next-to-next-to-leading order (NNNLO or N3LO) corrections is investigated for the first time. Phenomenologically, the proton central PDFs in this perturbative Quantum Chromo Dynamics (pQCD) analysis are defined based on the full seven data sets from HERA I and II combined. It is shown that, the LHC ATLAS jet cross sections data at $ \sqrt{s} = 7$ TeV on the HERA I and II combined data reduces the error band of proton PDFs. Particularly, the un…
Precision QED \otimes QCD Resummation Theory for LHC Physics: IR-Improved Scheme for Parton Distributions, Kernels, Reduced Cross Sections with Shower/ME Matching
MSTW PDFs and impact of PDFs on cross sections at Tevatron and LHC
我们简要地总结了“MSTW 2008”的部分子分布函数（PDF）的确定，以及随后的后续研究，然后再回顾一些热门的问题，在Tevatron和LHC的截面的PDF依赖。我们更新了最近发表的基准标准模型总截面（W，Z，gg->H和t-tbar生产）在7 TeV LHC的研究，在那里我们占所有公开可用的PDF集，我们比较LHC数据的W，Z，和t-tbar生产。我们显示的灵敏度的希格斯截面的胶子分布，然后我们证明的能力的Tevatron喷流数据，以及LHC的t-tbar数据，区分PDF集与不同的高x胶子分布。我们讨论了从深度非弹性散射数据中提取强耦合α_S的相关问题，并得出结论：为了得到有意义的结果，需要对高x胶子分布进行直接的数据约束。因此，我们不鼓励使用PDF集获得的“非全球”适合高x胶子分布不直接受数据的约束。
The W boson production cross section at the LHC through O(alpha_s^2)
我们计算了对全微分截面pp \to W X \to l νX的O（α_s^2）QCD修正，保留了自旋关联的所有影响。这些修正的知识使得有可能计算高精度的W玻色子的生产率和接受在大型强子对撞机，受到现实削减的轻子和丢失的能量分布。对于某些选择的削减，我们发现大的修正时，从下一个到领先的顺序（NLO）到下一个到下一个到领先的顺序（NNLO）在微扰理论。这些修正是显着大于部分子簇射事件发生器合并NLO计算得到的。我们的计算可以用来评估和显着减少QCD的不确定性在许多研究的$W$玻色子生产计划在大型强子对撞机。
The vector bosons production at the Large Hadron Collider makes it possible to investigate in detail the basic structure of electroweak interactions. Besides the LHC with a good accuracy will be measure production of weak bosons ($pp \to W^+W^-$). The production of weak bosons with photon ($pp \to W^+W^-γ$) provides an increasingly powerful handle at higher center-of-mass energies. We present phenomenological results for $WWγ$ production in proton-proton interaction at the Large Hadron Collider. In this paper, we calculate the total and differential cross sections. We consider the dependence o…
In this work, the impact of recent measurements of heavy-flavour production in $pp$ collisions on parton distribution functions (PDFs) and their uncertainties is studied. In this regard, the absolute and normalised cross sections of beauty hadron production measured by LHCb at center-of-mass energy of 7 TeV and 13 TeV are separately included in the next-to-leading order (NLO) global QCD analysis together with the measurements of the inclusive and heavy-flavour production cross sections at HERA. It is illustrated that the heavy-flavour data of the LHCb experiment impose additional constraints o…
