Related papers: Comments on a new `full colour' parton shower
The effective restoration of the U_{A}(1) symmetry is revisited by implementing the functional renormalization group approach combining with the 2+1 flavor Polyakov-loop quark-meson model. A temperature-dependent 't Hooft term is taken to…
We develop an algorithmic framework for graph colouring that reduces the problem to verifying a local probabilistic property of the independent sets. With this we give, for any fixed $k\ge 3$ and $\varepsilon>0$, a randomised…
We present an algorithm to evaluate the exact, tree-level matrix elements for multi-parton processes in QCD. We tested this technique, based on the recursive evaluation of the S-matrix, on processes such as gg -> n gluons and q qbar -> n…
We present an algorithm to include the correlation between the production and decay planes of gluons in a parton-shower simulation. The technique is based on identifying the charge currents responsible for the creation and annihilation of…
Multiobjective design optimization problems require multiobjective optimization techniques to solve, and it is often very challenging to obtain high-quality Pareto fronts accurately. In this paper, the recently developed flower pollination…
We present a new approach to combine multiple NLO parton-level calculations matched to parton showers into a single inclusive event sample. The method provides a description of hard multi-jet configurations at next-to leading order in the…
I show that Sudakov resummation takes a transparent form if one deals with the second logarithmic derivative of the short distance coefficient functions for deep inelastic scattering and the Drell-Yan process. A uniquely defined Sudakov…
We present the recent developments in exact amplitude-based resummation methods for non-Abelian gauge theories as they relate to precision LHC physics. We discuss QEDXQCD exponentiation, shower/ME matching, IR-improved DGLAP-CS theory and…
Nuclear shadowing and color glass condensate are possible only at sufficiently small x where parton clouds of different nucleons overlap in the longitudinal direction. Another condition vital for these effect, an overlap of partons in…
We determine the nuclear modifications of parton distribution functions of bound protons at scales $Q^2\ge 1.69$ GeV$^2$ and momentum fractions $10^{-5}\le x\le 1$ in a global analysis which utilizes nuclear hard process data, sum rules and…
Extending the well-known $SU(3)_C \times SU(3)_L \times SU(3)_R$ model of quarks and leptons to include a fourth $SU(3)_N$ gauge factor, a new realization is obtained, different from leptonic color, which contains a lepton/dark symmetry…
We describe a general method that enables us to obtain all the singular terms of helicity amplitudes of n-parton processes at one loop. The algorithm uses helicity amplitudes at tree level and simple color algebra. We illustrate the method…
We present a unified derivation of the resummation of Sudakov logarithms, directly from the factorization properties of cross sections in which they occur. We rederive in this manner the well-known exponentiation of leading and nonleading…
The spectrum of coherent gluon radiation from a quark-anti-quark pair experiencing multiple scatterings within a coloured medium is central for understanding in-medium parton cascades. Despite its foundational importance, current results…
Using data from the B factories and the Tevatron, we perform tests of how well non-leptonic B decays of the kind B -> D^{(*)}_{(s)} P, where P is a pion or kaon, are described within the factorization framework. We find that factorization…
It is shown that the colour dipole approach to hard scattering at high energy is fully compatible with k_T factorization at the leading logarithm approximation (in -log x_Bj). The relations between the dipole amplitudes and unintegrated…
We reveal the direct link between the jet clustering algorithms recently proposed by Howard Georgi and parton shower kinematics, providing firm foundation from the theoretical side. The kinematics of this class of elegant algorithms is…
The operator in a parton shower algorithm that represents the imaginary part of virtual Feynman graphs has a non-trivial color structure and is large because it is proportional to a factor of $4\pi$. In order to improve the treatment of…
In this thesis, we present automated, process-independent methods for the calculation of QED real radiative corrections. We review the construction of a parton shower based on Catani-Seymour dipole subtraction, and thus detail the…
We consider the k-strong conflict-free coloring of a set of points on a line with respect to a family of intervals: Each point on the line must be assigned a color so that the coloring has to be conflict-free, in the sense that in every…