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Related papers: Note on the CMS multiplicity distributions

200 papers

The ALICE collaboration recently reported the mean transverse momentum as a function of charged-particle multiplicity for different pp-collisions classes defined based on the "jettiness" of the event. The event "jettiness" is quantified…

High Energy Physics - Phenomenology · Physics 2024-01-15 Antonio Ortiz , Lizardo Valencia Palomo , Victor Manuel Minjares Neriz

The "Underlying Event" at CMS (under nominal and start-up conditions) is studied by examining charged particle and momentum densities in the "transverse" region in charged particle jet production. The predictions of various QCD models with…

High Energy Physics - Experiment · Physics 2008-10-28 Yuan Chao

The PYTHIA program can be used to generate high-energy-physics 'events' with sets of outgoing particles produced in the interactions between two incoming particles. The objective is to provide a representation, as accurate as possible, of…

High Energy Physics - Phenomenology · Physics 2010-05-24 Sparsh Navin

PYTHIA version 6 represents a merger of the PYTHIA 5, JETSET 7 and SPYTHIA programs, with many improvements. It can be used to generate high-energy-physics `events', i.e. sets of outgoing particles produced in the interactions between two…

High Energy Physics - Phenomenology · Physics 2008-11-26 Torbjörn Sjöstrand , Patrik Edén , Christer Friberg , Leif Lönnblad , Gabriela Miu , Stephen Mrenna , Emanuel Norrbin

We present a combined analysis of the Pythia 8 event generator using accelerator data and evaluate its impact on air shower observables. Reliable simulations with event generators are essential for particle physics analyses, achievable…

High Energy Astrophysical Phenomena · Physics 2025-09-19 Michael Windau , Chloé Gaudu , Karl-Heinz Kampert , Kevin Kröninger

It is shown that at collider energies experimental multiplicity distributions are well parameterized by a sum of Gupta-Sarma distributions. This extends earlier description of the lower energy data by the two parameter sum of Poissonians.…

High Energy Physics - Phenomenology · Physics 2016-08-25 O. G. Tchikilev

In this article we describe Professor, a new program for tuning model parameters of Monte Carlo event generators to experimental data by parameterising the per-bin generator response to parameter variations and numerically optimising the…

High Energy Physics - Phenomenology · Physics 2010-01-06 Andy Buckley , Hendrik Hoeth , Heiko Lacker , Holger Schulz , Jan Eike von Seggern

A mixture of multivariate contaminated normal distributions is developed for model-based clustering. In addition to the parameters of the classical normal mixture, our contaminated mixture has, for each cluster, a parameter controlling the…

Methodology · Statistics 2016-05-20 Antonio Punzo , Paul D. McNicholas

By deriving a general expression for multiplicity distribution (a conditional probability distribution) in statistical model, we demonstrate the mismatches between experimental measurements and previous theoretical calculations on…

Nuclear Theory · Physics 2016-05-31 Hao-jie Xu

Monte Carlo Event Generators are tools for simulating outcomes of high-energy collisions and particle production in High Energy Physics (HEP), such as those conducted at the Large Hadron Collider (LHC). Two of the most widely used…

High Energy Physics - Experiment · Physics 2025-11-05 Saliha Bashir , Agnieszka Obłąkowska-Mucha , Gloria Corti

We generalize and extend the recently proposed method to account for contributions of system size (or volume/participant) fluctuations to the experimentally measured moments of particle multiplicity distributions. We find that in the…

Nuclear Theory · Physics 2024-03-07 Romain Holzmann , Volker Koch , Anar Rustamov , Joachim Stroth

The PYTHIA Monte Carlo (PMC), first introduced more than thirty years ago, remains a popular simulation tool both for analysis of $p$-$p$ collision dynamics and for detector design and calibration. The PMC assumes that almost all produced…

High Energy Physics - Phenomenology · Physics 2019-07-24 Thomas A. Trainor

The PYTHIA program can be used to generate high-energy-physics `events', i.e. sets of outgoing particles produced in the interactions between two incoming particles. The objective is to provide as accurate as possible a representation of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Torbjörn Sjöstrand , Leif Lönnblad , Stephen Mrenna

A three-parameter discrete distribution is developed to describe the multiplicity distributions observed in total- and limited phase space volumes in different collision processes. The probability law is obtained by the Poisson transform of…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. Hegyi

This paper presents a new set of parameters ("tunes") for the underlying-event model of the HERWIG 7 event generator. These parameters control the description of multiple-parton interactions (MPI) and colour reconnection in HERWIG 7, and…

High Energy Physics - Experiment · Physics 2021-04-15 CMS Collaboration

Data analyses in hadron collider physics depend on background simulations performed by Monte Carlo (MC) event generators. However, calculational limitations and non-perturbative effects require approximate models with adjustable parameters.…

High Energy Physics - Phenomenology · Physics 2011-04-20 Andy Buckley , Hendrik Hoeth , Heiko Lacker , Holger Schulz , Jan Eike von Seggern

Current and future neutrino oscillation experiments utilize information of hadronic final states to improve sensitivities on oscillation parameters measurements. Among the physics of hadronic systems in neutrino interactions, the…

High Energy Physics - Phenomenology · Physics 2016-12-21 Teppei Katori , Pierre Lasorak , Shivesh Mandalia , Ryan Terri

State-of-the-art theoretical predictions accurate to next-to-leading order QCD interfaced with {\sc pythia} and {\sc herwig} are tested by comparing the unfolded $t\bar{t}$ differential data collected with the CMS detector at 8 TeV and 13…

High Energy Physics - Experiment · Physics 2019-08-13 B. Bilin

We consider the problem of model multiplicity in downstream decision-making, a setting where two predictive models of equivalent accuracy cannot agree on the best-response action for a downstream loss function. We show that even when the…

Machine Learning · Computer Science 2024-05-31 Ally Yalei Du , Dung Daniel Ngo , Zhiwei Steven Wu

HEP event generators aim to describe high-energy collisions in full exclusive detail. They combine perturbative matrix elements and parton showers with dynamical models of less well-understood phenomena such as hadronization, diffraction,…

High Energy Physics - Phenomenology · Physics 2014-12-12 Peter Skands