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Related papers: Quark spin effects in $e^+e^-$ annihilation: a Mon…

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Final state radiation in the process $e^+e^-\to\pi^+\pi^-$ is considered for the cuts used in the analysis of KLOE data at large angles. By means of a Monte Carlo event generator FEVA, effects of non-pointlike behaviour of pions are…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Pancheri , O. Shekhovtsova , G. Venanzoni

We study the fragmentation of a transversely polarized quark into a non collinear (k_T not= 0) spinless hadron and the fragmentation of an unpolarized quark into a non collinear transversely polarized spin 1/2 baryon. These nonperturbative…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Anselmino , D. Boer , U. D'Alesio , F. Murgia

At the KATRIN experiment, the electron antineutrino mass is inferred from the shape of the $\beta$-decay spectrum of tritium. Important systematic effects in the Windowless Gaseous Tritium Source (WGTS) of the experiment include the energy…

Instrumentation and Methods for Astrophysics · Physics 2022-10-05 Jonas Kellerer , Felix Spanier

We present a new Fortran Monte Carlo generator to simulate black hole events at CERN's Large Hadron Collider. The generator interfaces to the PYTHIA Monte Carlo fragmentation code. The physics of the BH generator includes, but not limited…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Cavaglia , R. Godang , L. Cremaldi , D. Summers

The observation of heavy-ion-like behaviour in pp collisions at the LHC suggests that more physics mechanisms are at play than traditionally assumed. The introduction e.g. of quark-gluon plasma or colour rope formation can describe several…

High Energy Physics - Phenomenology · Physics 2017-03-08 Nadine Fischer , Torbjörn Sjöstrand

The multiple hadron production in the events induced by the heavy primary quarks in $e^+e^-$ annihilation is reconsidered with account of corrected experimental data. New value for the multiplicity in $b\bar{b}$ events is presented on the…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. V. Kisselev , V. A. Petrov

We study the kinematic distributions of top--antitop quark pairs produced at the Tevatron, including the effects of initial state and final state multiple soft gluon emission, using the Collins--Soper--Sterman resummation formalism. The…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. Mrenna , C. -P. Yuan

Software package for Monte-Carlo simulation of e+e- exclusive annihilation channels written in the C++ language for Linux/Solaris platforms has been developed. It incorporates matrix elements for several mechanisms of multipion production…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Anipko , S. Eidelman , A. Pak

This work reports on a method for uncertainty estimation in simulated collider-event predictions. The method is based on a Monte Carlo-veto algorithm, and extends previous work on uncertainty estimates in parton showers by including…

High Energy Physics - Phenomenology · Physics 2024-05-29 Christan Bierlich , Philip Ilten , Tony Menzo , Stephen Mrenna , Manuel Szewc , Michael K. Wilkinson , Ahmed Youssef , Jure Zupan

We study the transverse momentum dependent (TMD) evolution of the Collins azimuthal asymmetries in $e^+e^-$ annihilations and semi-inclusive hadron production in deep inelastic scattering (SIDIS) processes. All the relevant coefficients are…

High Energy Physics - Phenomenology · Physics 2016-01-20 Zhong-Bo Kang , Alexei Prokudin , Peng Sun , Feng Yuan

A detailed study of the di-boson Monte Carlo programs Pythia, MC@NLO and the program of Baur, Han and Ohnemus (BHO) is performed. None of these programs cover all aspects of di-boson production. The BHO code is used to produce event weights…

High Energy Physics - Phenomenology · Physics 2008-03-25 Gideon Bella

We study the $p/\pi$ ratio in jets produced in simulated proton-proton collisions at $\sqrt{s_{NN}}=7~\mathrm{TeV}$ using Pythia $6.4$ Monte-Carlo generator. We compare the $p/\pi$ ratio in the selected quark-like and gluon-like jets to a…

High Energy Physics - Phenomenology · Physics 2014-03-04 Sona Pochybova

An important tool for the analysis of results of numerical simulations of lattice QCD is chiral perturbation theory. In Wilson chiral perturbation theory the effects of the finite lattice spacing $a$ are taken into account. In recent years…

High Energy Physics - Lattice · Physics 2016-05-31 Sebastian Engelnkemper , Gernot Münster

The qualitative results for string rotation in the frame of Relativistic Flux Tube Model and the quantitative and qualitative results for decay of massive open string states of string theory are used as the basic principles in the Monte…

High Energy Physics - Phenomenology · Physics 2007-05-23 Vladimir Lugovoi

Quark model intrinsic wave functions of highly energetic pions in the reaction \bar pp->\pi^-\pi^+ are subjected to a relativistic treatment. The annihilation is described in a constituent quark model with A2 and R2 flavor-flux topology and…

Nuclear Theory · Physics 2009-11-10 B. El-Bennich , W. M. Kloet

The Quark Gluon String Model (QGSM) reproduces well the global characteristics of the $pp$ collisions at RHIC and LHC, e.g., the pseudorapidity and transverse momenta distributions at different centralities. The main goal of this work is to…

High Energy Physics - Phenomenology · Physics 2015-05-28 M. S. Nilsson , L. V. Malinina , J. Bleibel , L. V. Bravina , E. E. Zabrodin

Longitudinal polarization of Lambda produced in $e^+e^-$ annihilation at LEP energies is calculated in a picture for the spin content of Lambda which is consistent with the polarized deep inelastic lepton-nucleon scattering data and SU(3)…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. Boros , Liang Zuo-tang

We present an implementation of the Bose - Einstein effect in a Monte Carlo generator for $W^-W^+ $ production in the $e^-e^+$ annihilation by means of the weight method. We check that the shift of the W mass in four jet events due to this…

High Energy Physics - Phenomenology · Physics 2016-08-15 K. Fiałkowski , R. Wit

The pion structure function is investigated in a simple model, where pion and constituent quark fields are coupled through the simplest pseudoscalar coupling. The imaginary part of the forward gamma* pi-> gamma* pi scattering amplitude is…

High Energy Physics - Phenomenology · Physics 2009-11-07 F. Bissey , J. R. Cudell , J. Cugnon , M. Jaminon , J. P. Lansberg , P. Stassart

The Collins fragmentation function is extracted from HERMES data on azimuthal single spin asymmetries in semi-inclusive deeply inelastic scattering, and BELLE data on azimuthal asymmetries in electron positron annihilations. A Gaussian…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. V. Efremov , K. Goeke , P. Schweitzer