Related papers: WPHACT 2.0: A fully massive Monte Carlo generator …
We study a quantum phase transition of electrons on a two-dimensional square lattice. Our lattice model preserves the full $\mathrm{O}(4)$ symmetry of free spin-$\frac{1}{2}$ Dirac fermions on a bipartite lattice. In particular, it not only…
We study the effects of non-commutative QED (NCQED) in fermion pair production, $\gamma + \gamma \to f + \bar{f}$ and Compton scattering, $e + \gamma \to e + \gamma$. Non-commutative geometries appear naturally in the context of…
Motivated by current searches for electroweak superpartners at the Large Hadron Collider, we present precision predictions for pair production of such particles in the framework of the Minimal Supersymmetric Standard Model. We make use of…
We present the Monte Carlo event generator WINHAC for the charged-current Drell-Yan process, i.e. single W-boson production with leptonic decays in hadronic collisions. It features multiphoton radiationwithin the Yennie-Frautschi-Suura…
The Monte Carlo event generator EKHARA was upgraded during last years. The upgrades presented here contain: a) the inclusion of new final states $e^+e^-\to e^+e^-\eta $, $e^+e^-\to e^+e^-\eta'$, $e^+e^-\to e^+e^- \chi_{c_i} $ and $e^+e^-\to…
The recently completed calculation of the full electroweak O(alpha) corrections to the charged-current four-fermion production processes e+e- --> nu_tau tau+ mu- anti-nu_mu, u anti-d mu- anti-nu_mu, and u anti-d s anti-c is briefly…
We describe recent additions to the WHIZARD 2 Monte-Carlo event generator which improve the physics description of lepton-collider event samples and speed up the calculation time required for cross sections and event generation.
The calculation of the full electroweak O(alpha) corrections to the charged-current four-fermion production processes e+e- --> nu_tau tau+ mu- anti-nu_mu, u anti-d mu- anti-nu_mu, and u anti-d s anti-c is briefly reviewed. The calculation…
We give a status report on new developments in the WHIZARD event generator, including NLO electroweak automation for $e^+e^-$ colliders, loop-induced processes, POWHEG matching, new features in the UFO interface and the current development…
In this paper the current release of the Monte Carlo event generator Sherpa, version 1.1, is presented. Sherpa is a general-purpose tool for the simulation of particle collisions at high-energy colliders. It contains a very flexible…
Radiative one-loop corrections to fermion pair production in $e^+e^-$ annihilation are calculated in the Minimal Supersymmetric Standard Model (MSSM). The size of the non-standard corrections is discussed for the process e^+e^- to mu^+mu^-…
We describe the physics and computational power of GRANIITTI Monte Carlo event generator, a new fully multithreaded engine designed for high energy diffraction, written in modern C++. The emphasis is especially on the low-mass domain of…
Fermion compositeness, and other types of new physics that can be described by the exchange of very massive particles, can manifest themselves as the result of an effective four-fermion contact interaction. In the case of the processes…
The program TOPAZ0 was developed for computing a variety of physical observables which are related to the e+e- annihilation into fermion pairs and to the large angle Bhabha scattering around the Z resonance. Among them, the Z parameters or…
The unitarity limit describes interacting particles where the range of the interaction is zero and the scattering length is infinite. We present precision benchmark calculations for two-component fermions at unitarity using three different…
We present a generator for lepton nucleon collisions in the DIS regime, focusing in particular on processes with a massive lepton and/or a massive quark in the final state. We have built a full code matching NLO QCD corrections to parton…
Building on the idea of numerically integrating differential equations satisfied by Feynman integrals, we propose a novel strategy for handling branch cuts within a numerical framework. We develop an integrator capable of evaluating a basis…
We derive the low-energy electroweak effective lagrangian for the case of additional heavy, unmixed, sequential fermions. Present LEP1 data still allow for the presence of a new quark and/or lepton doublet with masses greater than $M_Z/2$,…
Recently, various cross sections of e+e- annihilation into hadrons were accurately measured in the energy range from 0.37 to 1.39 GeV with the CMD-2 detector at the VEPP-2M collider. In the pi+pi- channel a systematic uncertainty of 0.6%…
One-dimensional massive quantum particles (or 1+1-dimensional random walks) with short-ranged multi-particle interactions are studied by exact renormalization group methods. With repulsive pair forces, such particles are known to scale as…