Related papers: Recent Pythia 8 developments: Hard diffraction, Co…
We outline major ideas involved in discussion of color coherence phenomena (CCP) at intermediate energies. We point out that the recent advances in calculating cross sections of hard exclusive processes off light nuclei allow to use the…
We propose changes to the colour reconnection model in the Monte Carlo event generator Herwig in order to remove the quasi diffractive events from the soft multiple parton interactions. We then implement explicitly soft diffraction and show…
We discuss Hybrid Hadronization, a hadronization model which interpolates between string fragmentation in dilute parton systems and quark recombination in dense parton systems. We lay out the basic principles, discuss some details of the…
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…
We find a consistency between two different approaches of hard diffraction, namely the QCD dipole model and the Soft Colour Interaction approach. A theoretical interpretation in terms of S-Matrix and perturbative QCD properties in the small…
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…
The Pythia event generator is used in several contexts to study hadron and lepton interactions, notably $pp$ and $p\bar{p}$ collisions. In this article we extend the hadronic modelling to encompass the collision of a wide range of hadrons…
In this letter we propose the search of dark photons in the decay of pions produced by $\gamma \gamma$ interactions in ultraperipheral $PbPb$ collisions. The cross section is estimated considering an accurate treatment for the absorptive…
These lectures include an introduction to the partonic description of the proton, the photon and the `colour singlet', as seen in inclusive and semi-inclusive DIS, in $e^+e^-$ collisions, and in diffractive processes, respectively. Their…
The idea of diffractive processes with a hard scale involved, to resolve the underlying parton dynamics, was published 1985 and experimentally verified 1988. Today hard diffraction is an active research field with high-quality data and new…
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…
We study the dynamics of identified, strange, and multi-strange particle production in Pb--Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV using the recently developed Angantyr model, incorporated within PYTHIA8. We show the interplay…
Colour coherence in hard photoproduction is considered using the Monte Carlo event generators PYTHIA and HERWIG. Significant effects in the parton shower are found using multijet observables for direct and resolved photon induced reactions.…
Diffraction is an old subject which has received much interest in recent years due to the advent of diffractive hard scattering. We discuss some theoretical models and experimental results that have shown new striking effects, e.g. rapidity…
In this talk we introduce the main features of a QCD-based model in which the coupling $\alpha_{s}$ is constrained by an infrared mass scale. We show recent applications of this model to hadron-hadron collisions, gap survival probability…
PYTHIA is a general-purpose event generator for multiparticle production in high-energy physics. After a general introduction and program news survey, some areas of recent physics progress are considered: the matching to matrix elements,…
The effects of colour reconnection (CR) at $\mathrm{e}^+\mathrm{e}^-$ colliders are revisited, with focus on recently developed CR models. The new models are compared with the LEP2 measurements for $\mathrm{e}^+\mathrm{e}^- \to…
We investigate production of $J/\psi$ mesons in hadron-hadron collisions, defined as low invariant mass $c\bar{c}$ singlets produced in a mixture of perturbative and nonperturbative mechanisms provided by the PYTHIA Monte Carlo. We find…
Soft colour exchange models give a unified description of both diffractive and non-diffractive events, such that e-p and p-pbar collider data with and without rapidity gaps are well reproduced. We show that these models also describe the…
Color reconnection (CR) mechanism in PYTHIA model has been reported to be essential to describe the flow-like collective effect observed in high multiplicity $p$+$p$ and $p$+Pb collisions. In this work, we test this mechanism towards…