arXiv subjects

Doreen Wackeroth

Publications and source records attributed to Doreen Wackeroth.

23 records · Page 2Linked to original sources

arXiv2008

NLO QCD corrections to W-b-bbar and Z-b-bbar production

We present NLO QCD results for W/Z gauge boson production with bottom quark pairs at the Tevatron including full bottom-quark mass effects. We study the impact of QCD corrections on both total cross-section and invariant mass distribution of the bottom-quark pair. Including NLO QCD corrections greatly reduces the dependence of the tree-level cross-section on the renormalization and factorization scales. We also compare our calculation to a calculation that considers massless bottom quarks and find that the bottom-quark mass effects amount to about 8-10% of the total NLO QCD cross-section and can impact the shape of the bottom-quark pair invariant mass distribution, in particular in the low invariant mass region.

hep-ph↗

arXiv2007

SUSY QCD one-loop effects in (un)polarized top-pair production at hadron colliders

We study the effects of O(alpha_s) supersymmetric QCD (SQCD) corrections on the total production rate and kinematic distributions of polarized and unpolarized top-pair production in pp and p anti-p collisions. At the Fermilab Tevatron p anti-p collider, top-quark pairs are mainly produced via quark-antiquark annihilation, q anti-q -> t anti-t, while at the CERN LHC pp collider gluon-gluon scattering, g g -> t anti-t, dominates. We compute the complete set of O(alpha_s) SQCD corrections to both production channels and study their dependence on the parameters of the Minimal Supersymmetric Standard Model. In particular, we discuss the prospects for observing strong, loop-induced SUSY effects in top-pair production at the Tevatron Run II and the LHC.

hep-ph↗

arXiv2006

Electroweak Physics: Theoretical Overview

I give an overview of the theory status of predictions for single W and Z boson production at hadron colliders. I briefly report on work in progress for improvements necessary to match the anticipated high precision of electroweak measurements, such as the W mass and width, at the Fermilab Tevatron p anti-p and the CERN LHC pp colliders.

hep-ph↗

arXiv1999

Parity Violating Asymmetries in Top Pair Production at Hadron Colliders

We study loop-induced parity violating asymmetries in the strong production of polarized top quark pairs at $pp$ and $p \bar p$ colliders. The electroweak ${\cal O}(α)$ corrections to the helicity amplitudes of $q \bar q \to t \bar t$ and $gg \to t \bar t$ are evaluated in a two Higgs doublet model (2HDM) and the minimal supersymmetric standard model (MSSM). While observables in top quark pair production receive little contribution from standard electroweak interactions, it is possible that they can be significantly enhanced in a 2HDM and the MSSM. We find that the one-loop MSSM electroweak corrections can generate parity violating asymmetries in the total production rate of left- and right-handed top quark pairs up to about 1.7% at the upgraded Tevatron ($\sqrt{S}=2$ TeV) and 3% at the LHC ($\sqrt{S}=14$ TeV).

hep-ph↗

arXiv1997

Electroweak Radiative Corrections to Resonant Charged Gauge Boson Production

The electroweak O(alpha) contribution to the resonant single W production in a general 4-fermion process is discussed with particular emphasis on a gauge invariant decomposition into a QED-like and weak part. The cross section in the vicinity of the resonance can be represented in terms of a convolution of a `hard' Breit-Wigner-cross section, comprising the (m_t,M_H)-dependent weak 1-loop corrections, with an universal radiator function. The numerical impact of the various contributions on the W line shape are discussed, together with the concepts of s-dependent and constant width approach. Analytic formulae for the W decay width are also provided including the 1-loop electroweak and QCD corrections.

hep-ph↗