360 citations · 1.7k across the 34 of their papers we have counts for
32 papers · 1 filter
Examination of -factorization in a Yukawa theory
B. Guiot, A. van Hameren
We discuss the upper limit, , of the transverse-momentum integration performed in the -factorization formula. Based on explicit calculations in the Yukawa theo…
A new subtraction scheme at NLO exploiting the privilege of kT-factorization
Alessandro Giachino, Andreas van Hameren, Grzegorz Ziarko
We present a subtraction method for the calculation of real-radiation integrals at NLO in hybrid kT-factorization. The main difference with existing methods for collinear factoriza…
One-loop gauge invariant amplitudes with a space-like gluon
Etienne Blanco, Alessandro Giachino, Andreas van Hameren +1
Nowadays the particle physics has entered an era where high precision calculations are required in order to compare the theoretical predictions with the experimental data. In this…
Hybrid kT-factorization and impact factors at NLO
Andreas van Hameren, Leszek Motyka, Grzegorz Ziarko
In the hybrid kT-factorization formula, one initial-state parton momentum is space-like and carries non-vanishing transverse components, while the other is on-shell. We promote thi…
D and B-meson production using kt-factorization calculations in a variable-flavor-number scheme
B. Guiot, A. van Hameren
Within the framework of -factorization, we compute the differential cross section for the production of and mesons, using a general-mass variable-flavor-number scheme.…
Calculations with off-shell matrix elements, TMD parton densities and TMD parton showers
Marcin Bury, Andreas van Hameren, Hannes Jung +3
A new calculation using off-shell matrix elements with TMD parton densities supplemented with a newly developed initial state TMD parton shower is described. The calculation is bas…
Calculating off-shell one-loop amplitudes for -dependent factorization: a proof of concept
A. van Hameren
A method to define and calculate one-loop amplitudes with an off-shell space-like, or -dependent, gluon is presented. It introduces a practical regularization to deal with the…
QCD amplitudes with 2 initial spacelike legs via generalised BCFW recursion
Andreas van Hameren, Krzysztof Kutak, Mirko Serino
We complete the generalisation of the BCFW recursion relation to the off-shell case, allowing for the computation of tree level scattering amplitudes for full High Energy Factorisa…
KaTie: for parton-level event generation with k_T-dependent initial states
A. van Hameren
KaTie is a parton-level event generator for hadron scattering processes that can deal with partonic initial-state momenta with an explicit transverse momentum dependence causing th…
Forward di-jet production in p+Pb collisions in the small-x improved TMD factorization framework
A. van Hameren, P. Kotko, K. Kutak +3
We study the production of forward di-jets in proton-lead and proton-proton collisions at the Large Hadron Collider. Such configurations, with both jets produced in the forward dir…
Four-jet production in single- and double-parton scattering within high-energy factorization
Krzysztof Kutak, Rafal Maciula, Mirko Serino +2
We perform a first study of 4-jet production in a complete high-energy factorization (HEF) framework. We include and discuss contributions from both single-parton scattering (SPS)…
BCFW recursion for TMD parton scattering
A. van Hameren, M. Serino
We investigate the application of the BCFW recursion relation to scattering amplitudes with one off-shell particle in a Yang-Mills theory with fermions. We provide a set of conditi…
BCFW recursion for off-shell gluons
A. van Hameren
It is shown how tree-level multi-gluon helicity amplitudes with an arbitrary number of off-shell external gluons can be calculated via BCFW recursion. Compact expressions for helic…
Single-parton scattering versus double-parton scattering in the production of two pairs and charmed meson correlations at the LHC
Andreas van Hameren, Rafal Maciula, Antoni Szczurek
We compare results of exact calculations of single parton scattering (SPS) and double parton scattering (DPS) for production of and for meson correlations.…
Scattering amplitudes with off-shell quarks
A. van Hameren, K. Kutak, T. Salwa
We present a prescription to calculate manifestly gauge invariant tree-level scattering amplitudes for arbitrary scattering processes with off-shell initial-state quarks within the…
Three jet production and gluon saturation effects in p-p and p-Pb collisions within high-energy factorization
Andreas van Hameren, Piotr Kotko, Krzysztof Kutak
We analyze three jet production in the central-forward and forward rapidity regions in proton-proton and proton-lead collisions at LHC energies. Our calculation relies on high-ener…
Scattering amplitudes for high-energy factorization
A. van Hameren
A prescription is presented to construct manifestly gauge invariant tree-level scattering amplitudes with one or two off-shell initial-state gluons for processes with arbitrary par…
Helicity amplitudes for high-energy scattering
A. van Hameren, P. Kotko, K. Kutak
We present a prescription to calculate manifestly gauge invariant tree-level helicity amplitudes for arbitrary scattering processes with off-shell initial-state gluons within the k…
Helac-nlo
G. Bevilacqua, M. Czakon, M. V. Garzelli +5
Based on the OPP technique and the HELAC framework, HELAC-1LOOP is a program that is capable of numerically evaluating QCD virtual corrections to scattering amplitudes. A detailed…
NLO QCD calculations with HELAC-NLO
G. Bevilacqua, M. Czakon, M. V. Garzelli +5
Achieving a precise description of multi-parton final states is crucial for many analyses at LHC. In this contribution we review the main features of the HELAC-NLO system for NLO Q…
OneLOop: for the evaluation of one-loop scalar functions
A. van Hameren
OneLOop is a program to evaluate the one-loop scalar 1-point, 2-point, 3-point and 4-point functions, for all kinematical configurations relevant for collider-physics, and for any…
Kaleu: a general-purpose parton-level phase space generator
A. van Hameren
Kaleu is an independent, true phase space generator. After providing it with some information about the field theory and the particular multi-particle scattering process under cons…
The SM and NLO multileg working group: Summary report
T. Binoth, G. Dissertori, J. Huston +88
This report summarizes the activities of the SM and NLO Multileg Working Group of the Workshop "Physics at TeV Colliders", Les Houches, France 8-26 June, 2009.
Automated one-loop calculations: a proof of concept
A. van Hameren, C. G. Papadopoulos, R. Pittau
An algorithm, based on the OPP reduction method, to automatically compute any one-loop amplitude, for all momentum, color and helicity configurations of the external particles, is…