Korinna Christine Zapp
(CERN)
02/12/2013, 09:40
MPI & Monte Carlo
Talk
SHRiMPS, the new minimum bias model in SHERPA, is based on the successful Khoze-Martin-Ryskin model. The latter is a multi-channel eikonal model that by summing all multi-pomeron diagrams is capable of describing elastic and inelastic scattering, low mass and high mass diffractive dissociation and central exclusive production. The Monte Carlo realisation relies on the partonic interpretation...
Leif Lönnblad
(Lund University (SE))
02/12/2013, 10:05
MPI & Monte Carlo
Talk
We describe the status of the DIPSY program with emphasis on its application to heavy-ion collisions. The main advantage of the DIPSY model for heavy ions, is the inclusion of initial state correlations and fluctuations. We present preliminary results for pA collisions where small effects of fluctuations can be found in inclusive cross sections.
Andrzej Konrad Siodmok
(University of Manchester (GB))
02/12/2013, 10:30
MPI & Monte Carlo
Talk
We review the modelling of multiple interactions in the event generator Herwig++ and study implications of recent tuning efforts to Tevatron and LHC data. It is often said that measurements of the effective cross section for double-parton scattering, sigma_effective, are in contradiction with models of the final state of multi-parton interactions, but we show that the Herwig++ model is...
Richard Dryden Field
(University of Florida (US))
02/12/2013, 11:20
MPI & Monte Carlo
Talk
At CDF we study min-bias collisions (MB) and the “underlying event” (UE) using charged particles produced in proton-antiproton collisions at 300 GeV, 900 GeV, and 1.96 TeV. The 300 GeV and 900 GeV data are a result of the “Tevatron Energy Scan” which was performed just before the Tevatron was shut down. We use the direction of the leading charged particle in each event, PTmax, to define three...
Mr
Mohammed Zakaria
(University of Florida (US))
02/12/2013, 11:45
MPI & Monte Carlo
Talk
A measurement of the underlying event activity is performed on proton-proton collisions, for different centre-of-mass energies, using the CMS detector. The charged particles in the azimuthal region transverse to the leading track with transverse momentum larger than 0.5 GeV/c and at central pseudorapidities are studied. The measurements are compared with various theoretical predictions. A...
Maxim Azarkin
(Russian Academy of Sciences (RU))
02/12/2013, 12:10
MPI & Monte Carlo
Talk
Characteristics of multiparticle production in proton-proton collisions at a centre-of-mass energy of 7 TeV are presented as a function of the charged-particle multiplicity. The produced particles are separated into those belonging to jets and those belonging to the underlying event (UE). Results are compared to the predictions of the PYTHIA and HERWIG Monte Carlo event generators. For...
Deepak Kar
(University of Glasgow (GB))
02/12/2013, 12:35
MPI & Monte Carlo
Talk
Angular Structure Function (ASF) has been proposed as a way to study MPI contribution in large radius jets (arXiv:1201.2688v2 [hep-ph]). We extend the study to include more topologies and Monte Carlo models, and look at the traditional transverse regions used for probing the underlying event. The ASF gives a reasonable discrimination between MPI and hard scattered jets.
Mr
Christian Bierlich
(Lund University (SE))
04/12/2013, 09:00
MPI & Monte Carlo
Talk
The Lund string model for hadronisation provides an intuitive and strong physical picture of the hadronisation process by realising a linear confinement potential as a flux tube stretched between colour-singlet pairs. This picture was developed in the context of the very clean LEP environment, but faces some difficulties describing the hadro-chemistry in the busy environment of LHC, where flux...
Guy Paic
(Universidad Nacional Autonoma (MX))
04/12/2013, 09:25
MPI & Monte Carlo
Talk
Recently we have been studying the predictions of Pythia 8 with respect to several observables: the ratios of identified particles in the 2-6 GeV/c range the production of jets in Pythia in function of multiplicity and transverse sphericity and momentum correlations in the φ-η plane in function of multiplicity and transverse sphericity. In some cases the results of varying the number of MPI...
Anatoli Fedynitch
(KIT - Karlsruhe Institute of Technology (DE))
04/12/2013, 09:50
MPI & Monte Carlo
Talk
PHOJET is a well established multi-purpose Monte-Carlo generator, focused towards the simulation of minimum bias, diffractive and forward phenomena. It is relying on the ideas of Regge-Theory and the topological expansion of QCD. Multi parton interactions evolve naturally from the Eikonal structure of scattering amplitudes. Although the program is still widely applied in high-energy physics...
Prof.
Fritz, W. Bopp
(University of Siegen)
04/12/2013, 10:15
MPI & Monte Carlo
Talk
It is well known that jets or mini-jets in heavy ion and to a degree in dense proton reactions are suppressed as a consequence of re-scattering. Here we consider indirect consequences of such re-scattering. It is done in a toy model with a fixed survival length and a uniform emission density, adjusted to fit observed suppression of jets. In transverse direction the simple picture provides a...
Krzysztof Bozek
(K)
04/12/2013, 10:35
MPI & Monte Carlo
Talk
I would like to present a Monte Carlo based method that solves the non-linear Balitsky–Kovchegov (BK) equation in the integral form. The approach is based on reformulation of the BK equation as a system of linear integral equations through the Newton–Kantorovich transformation. The system is then solved through a Markov Chain Monte Carlo (MCMC) algorithm. Our results agree at the level of...
amanda sarkar
04/12/2013, 11:25
MPI & Monte Carlo
Talk
This note presents the HERAPDF1.5 PDF set evolved to leading order (LO) s using DGLAP evolution equations. This LO PDF is particularly useful for Monte Carlo event generators, based on LO matrix elements plus parton showers. The PDF fit is based on DIS data alone, using the H1 and ZEUS experiments at HERA.
Anastasia Grebenyuk
(Deutsches Elektronen-Synchrotron (DE))
04/12/2013, 11:50
MPI & Monte Carlo
Talk
Charged particle production in deep-inelastic ep scattering is measured with the H1 detector at HERA. The kinematic range of the analysis covers low photon virtualities, 5 < Q^2 < 100 GeV^2, and small values of Bjorken-x, 10^{-4} < x < 10^{-2}. The analysis is performed in the hadronic centre-of-mass system. The charged particle densities are measured as a function of pseudorapidity (eta^*)...
Vardan Khachatryan
(ANSL (Yerevan Physics Institute) (AM))
04/12/2013, 12:15
MPI & Monte Carlo
Talk
The pseudorapidity distributions of charged particles produced in proton-proton collisions at a centre-of-mass energy of 8 TeV are measured in the ranges |eta| < 2.2 and 5.3 < |eta| < 6.4, by the CMS and TOTEM detectors, respectively. The measurement is performed with a one-side TOTEM trigger, which is sensitive to 99% of non-diffractive interactions and all diffractive interactions with...
Paolo Gunnellini
(Deutsches Elektronen-Synchrotron (DE))
04/12/2013, 12:40
