As part of the DESY summer student program 2021, transverse momentum dependent (TMD) parton distributions obtained from the Parton Branching (PB) method were combined with next-to-leading-order (NLO) using the POWHEG method. Computations of the resulting Drell-Yan (DY) transverse momentum spectrum were performed. A good agreement of the theoretical predictions with the measurement performed by the CMS experiment at the center-of-mass energy of 13 TeV is found, at low and intermediate DY $p_{\rm T}$. The new scale choice option for the matching has been included in the CASCADE event generator.
We use the POWHEG method to perform parton-shower matching for Drell-Yan production of W and Z bosons at the LHC at NLO QCD and NLO electroweak accuracy. In particular, we investigate an improved treatment of the vector-boson resonances within the POWHEG method. We employ an independent implementation of the POWHEG method and compare to earlier results within the POWHEGBOX. On the technical side, we provide the FKS formalism for photon-radiation off fermions within mass regularization.
A Positive-Weight Next-to-Leading Order Monte Carlo Simulation of Drell-Yan Vector Boson Production
在Herwig++ Monte Carlo事件发生器中，将正权重次领先阶（NLO）匹配方案（POWHEG）应用于Drell-Yan矢量玻色子产生.这种方法一致地结合了NLO计算和部分子簇射模拟，而不产生负权重事件。该模拟包括一个完整的实施截断簇射所需的正确描述软排放的角度有序的部分子簇射，第一次。结果进行了比较Tevatron W和Z的生产数据和预测的规范玻色子在LHC提出的横向动量谱。
Production of a forward Drell-Yan lepton pair accompanied by a jet separated by a large rapidity interval is proposed to study the BFKL evolution at the LHC. Several observables to be measured are presented including the azimuthal angle dependence of the lepton pair which allows to determine Drell-Yan structure functions.
The Helicity Structure Functions in the Drell-Yan process are discussed in a framework of Parton Reggeization Approach, which includes the transverse momentum of initial-state partons in a way compatible with QED gauge-invariance. Relationships with conventional Transverse Momentum Dependent Parton Model formalism are clarified.
We calculate the gauge invariant Drell-Yan-like hadron tensors. In connection with new COMPASS results, we propose the single spin asymmetry which probes gluon poles together with chiral-odd and time-odd functions. The relevant pion production as a particular case of Drell-Yan-like process has been discussed. For the meson-induced Drell-Yan process, we model an analog of the twist three distribution function, which is a collinear function in inclusive channel, by means of two non-collinear distribution amplitudes which are associated with exclusive channel. This modelling demonstrates the fund…
Drell Yan production is a sensitive probe of new physics and as such has been calculated to high order in both the electroweak and QCD sectors of the Standard Model, allowing for precision comparisons between theory and data. Here we extend these calculations to the Standard Model Effective field theory (SMEFT) and present the NLO QCD and electroweak contributions to the neutral Drell Yan process that are linear in the Wilson coefficients of the SMEFT theory.
The Drell-Yan process is a copious source of lepton pairs at high energy and is measured with great precision at the Large Hadron Collider (LHC). Barring any new light particles, beyond the Standard Model effects can be studied in Drell-Yan production using an effective field theory. At tree level, new 4-fermion interactions dominate, while at one loop operators modifying 3-gauge boson couplings contribute effects that are enhanced at high energy. We study the sensitivity of the neutral Drell-Yan process to these dimension-6 operators and compare the sensitivity to that of $W^+W^-$ pair produc…
We discuss the Drell-Yan dilepton production using the transverse momentum dependent parton distributions evolved with the Catani-Ciafaloni-Fiorani-Marchesini-Kwieciński (CCFM-K) equations in the single loop approximation. Such equations are obtained assuming angular ordering of emitted partons (coherence) for $x\sim 1$ and transverse momentum ordering for $x \ll 1$. This evolution scheme also contains the Collins-Soper-Sterman (CSS) soft gluon resummation. We make a comparison with a broad class of data on transverse momentum spectra of low mass Drell-Yan dileptons.
We calculate the hadron tensor related to the photon-induced Drell-Yan process, with incoming nucleon being transversally polarised. We predict the new single spin asymmetry which probes gluon poles and which is expressed in terms of photon (both chiral-odd and chiral-even) distribution amplitudes and chiral-odd nucleon function stemming from the nucleon transverse polarization.
I report on precision comparisons of theoretical predictions for Drell-Yan (DY) transverse momentum spectra from two approaches: the analytical resummation approach based on Collins-Soper-Sterman (CSS) formalism and the parton branching (PB) approach to the evolution of transverse momentum dependent (TMD) parton distributions.
