In everyday research, it is tacitly assumed that the scattering cross-sections have fixed values for the given particle species, centre-of-mass energy, and particle polarizations. However, this assumption has been called into question after several observations of suppression of high-energy bremsstrahlung. This process will play a major role in experiments at the future Electron-Ion Collider, and we show here how variations of the bremsstrahlung cross-section can be profoundly studied there using the lateral beam displacements. In particular, we predict very strong increase of the observed cross-sections for large beam separations. We also discuss the relation of these elusive effects to other quantum phenomena occurring over macroscopic distances. In this context, spectacular and possibly useful properties of the coherent bremsstrahlung at the EIC are also evaluated.
The total top quark pair production cross-section at hadron colliders through O(alpha_S^4)
我们计算了反应gg \to t \bar t + X对总截面的次-次-首阶（NNLO）QCD修正.与我们以前计算的部分子通道一起，本文的结果完成了强子对撞机上总顶对产生截面的NNLO QCD修正。补充固定的顺序与软胶子remation与下一个到下一个到领先的对数精度的结果，我们估计，由于未知的高阶修正的理论不确定性，这可观察到的约3%，在LHC和2.2%，在Tevatron。我们观察到一个很好的协议之间的标准模型的预测和现有的实验测量。这个观测的非常高的理论精度允许在部分子分布函数和新的物理搜索的审查一个新的水平。
In this contribution we review the status of inclusive jet cross sections at hadron colliders in perturbative QCD, studying in particular the renormalisation and factorisation scale dependence of the one-jet inclusive cross section at NNLO.
Higgs boson production at hadron colliders: differential cross sections through next-to-next-to-leading order
本文计算了微扰QCD中次次领头阶下胶子熔合通道中希格斯玻色子产生的全微分截面。我们应用\cite{Anastasiou:2003gr}中介绍的方法计算双实发射修正。我们的计算允许在反应$hh \to H + X$的最终状态任意削减。它可以很容易地扩展到包括希格斯玻色子衰变到可观察的最终状态。在这封信中，我们讨论了计算的最重要的特点，并提出了一些物理应用的例子，说明可以使用我们的结果进行研究的可观测量的范围。我们计算了希格斯玻色子的NNLO快度分布，并计算了喷注活动否决的NNLO快度分布。
The inclusive cross sections of W$^+$, W$^-$, and Z boson production from 34 different measurements performed in proton-(anti)proton collisions at center-of-mass energies $\sqrt{s}$ = 1.8--13 TeV, are compared to perturbative QCD calculations at next-to-next-to-leading-order (NNLO) accuracy with four sets of parton distributions functions (CT14, HERAPDF2.0, MMHT14, and NNPDF3.0 PDFs) and varying values of the strong coupling constant at the Z mass pole, $α_s(m_Z)$. The data-theory agreement is good within the experimental and theoretical uncertainties, with the CT14 and MMHT14 parton densities…
NNLO corrections to top pair production at hadron colliders: the quark-gluon reaction
我们计算了反应qg \to t \bar t + X中包含的总顶对产生截面的次-次-首阶QCD修正。我们发现中等O（1%）的修正，在Tevatron和LHC的中心值。横截面的尺度变化在Tevatron中保持不变，在LHC中显着减少。我们发现，最近推出的近似的基础上的高能量限制的顶部对截面显着偏离的确切结果。在目前的工作中得出的结果包括在1.4版的程序顶++。计算反应gg \to t \bar t+X的工作正在进行中。
Gluon Fusion Contribution to $VHj$ Production at Hadron Colliders
我们研究了胶子-胶子融合产生的电弱矢量玻色子和带有喷注的希格斯玻色子玻色子。在前导序列中，这些过程发生在单循环级别。这些单圈过程的振幅是规范不变的和有限的。因此，它们对相应的强子截面和运动学分布的贡献可以分别计算。我们目前的大型强子对撞机及其讨论升级的结果。我们发现胶子-胶子单圈过程对$γH j$的产生起主要作用。我们在$gg\to Z H j$振幅中观察到相消干涉效应。我们还发现在高横动量和中心快度区，胶子-胶子熔合产生的$ZHj$的截面与夸克-夸克和夸克-胶子通道产生的截面相当。
The claim that the $X(3872)$ meson cannot be a charm-meson molecule because its prompt production cross section at hadron colliders is too large is based on an upper bound in terms of a cross section for producing charm-meson pairs. Assuming $X$ is sufficiently weakly bound, we derive an equality between the $X$ cross section and a charm-meson pair cross section that takes into account the threshold enhancement from the $X$ resonance. The cross section for producing $X$ is equal to that for producing $D^{*0} \bar{D}^0$ integrated up to a relative momentum $k_\mathrm{max} = 7.7\,γ_X$, where $γ_…
We present the Higgs boson production cross section at Hadron colliders in the gluon fusion production mode through N3LO in perturbative QCD. Specifically, we work in an effective theory where the top quark is assumed to be infinitely heavy and all other quarks are considered to be massless. Our result is the first exact formula for a partonic hadron collider cross section at N3LO in perturbative QCD. Furthermore, this result represents the first analytic computation of a hadron collider cross section involving elliptic integrals. We derive numerical predictions for the Higgs boson cross secti…
For the search for electroweak (EW) particles in the Minimal Supersymmetric Standard Model (MSSM) as well as for future precision analyses of these particles an accurate knowledge of their production and decay properties is mandatory. We evaluate the cross sections for the chargino, neutralino and slepton production at e+e- colliders in the MSSM with complex parameters (cMSSM). The evaluation is based on a full one-loop calculation of all possible production channels including soft and hard photon radiation. The dependence of the cross sections on the relevant cMSSM parameters is analyzed nume…
