scholarly journals Next-to-leading order slepton pair production at hadron colliders

1998 ◽  
Vol 57 (9) ◽  
pp. 5871-5874 ◽  
Author(s):  
Howard Baer ◽  
B. W. Harris ◽  
Mary Hall Reno
2003 ◽  
Vol 18 (08) ◽  
pp. 1357-1364 ◽  
Author(s):  
W. BERNREUTHER ◽  
A. BRANDENBURG ◽  
Z. G. SI ◽  
P. UWER

Top quark-antiquark [Formula: see text] pairs will be produced copiously at the Tevatron collider and in huge numbers at the LHC. This will make possible detailed investigations of the properties and interactions of this quark flavor. The analysis and interpretation of future data requires precise predictions of the hadronic production of [Formula: see text] pairs and of their subsequent decays. In this talk the reactions [Formula: see text], [Formula: see text] are considered and results are presented of our calculation6 of the dilepton angular distribution at next-to-leading order QCD, keeping the full dependence on the spins of the intermediate [Formula: see text] state. The angular distribution is determined for different choices of reference axes that can be identified with the t and [Formula: see text] spin axes. While the QCD corrections to the leading-order distribution turn out to be small in the case of the LHC, we find them to be sizeable in the case of the Tevatron and find, moreover, the angular distribution to be sensitive to the parton content of the proton.


2011 ◽  
Vol 83 (11) ◽  
Author(s):  
Tom Melia ◽  
Kirill Melnikov ◽  
Raoul Röntsch ◽  
Giulia Zanderighi

2006 ◽  
Vol 21 (02) ◽  
pp. 89-109 ◽  
Author(s):  
S. DAWSON ◽  
C. B. JACKSON ◽  
L. REINA ◽  
D. WACKEROTH

We review the present status of the QCD corrected cross-sections and kinematic distributions for the production of a Higgs boson in association with bottom quarks at the Fermilab Tevatron and CERN Large Hadron Collider. Results are presented for the Minimal Supersymmetric Standard Model where, for large tan β, these production modes can be greatly enhanced compared to the Standard Model case. The next-to-leading order QCD results are much less sensitive to the renormalization and factorization scales than the lowest order results, but have a significant dependence on the choice of the renormalization scheme for the bottom quark Yukawa coupling. We also investigate the uncertainties coming from the Parton Distribution Functions and find that these uncertainties can be comparable to the uncertainties from the remaining scale dependence of the next-to-leading order results. We present results separately for the different final states depending on the number of bottom quarks identified.


2019 ◽  
Vol 79 (12) ◽  
Author(s):  
Jean-Philippe Lansberg ◽  
Hua-Sheng Shao ◽  
Nodoka Yamanaka ◽  
Yu-Jie Zhang

AbstractPrompt double-$$J/\psi $$J/ψ production at high-energy hadron colliders can be considered as a golden channel to probe double parton scatterings (DPS)—in particular to study gluon–gluon correlations inside the proton—and, at the same time, to measure the distribution of linearly-polarised gluons inside the proton. Such studies, however, require a good control of both single parton scatterings (SPS) and DPS in the respective regions where they are carried out. In this context, we have critically examined two mechanisms of SPS that may be kinematically enhanced where DPS are thought to be dominant, even though they are either at higher orders in the strong-coupling or velocity expansion. First, we have considered a gauge-invariant and infrared-safe subset of the loop-induced contribution via colour-singlet (CS) transitions. We have found it to become the leading CS SPS contributions at large rapidity separation, yet too small to account for the data without invoking the presence of DPS yields. Second, we have surveyed the possible colour-octet (CO) contributions using both old and up-to-date non-perturbative long-distance matrix elements (LDMEs). We have found that the pure CO yields crucially depend on the LDMEs. Among all the LDMEs we used, only two result into a visible modification of the NRQCD (CS+CO) yield, but only in two kinematical distributions measured by ATLAS, those of the rapidity separation and of the pair invariant mass. These modifications, however, do not impact the control region used for their DPS study.


Sign in / Sign up

Export Citation Format

Share Document