A correct modelling of the underlying event in proton-proton collisions is important for the proper simulation of kinematic distributions of high-energy collisions. The ATLAS collaboration extended previous studies at 7 TeV with a leading track or jet or Z boson by a new study at 13 TeV, measuring the number and transverse-momentum sum of charged particles as a function of pseudorapidity and...
Measurement of Underlying Event activity performed using proton-proton collision data collected by the CMS detector will be presented. To check the energy dependence of Underlying Event activity, the results are compared with previous measurements from different experiments at different center-of-mass energies.
Speakers
We present a new model for soft interactions in the event-generator Herwig. The model consists of two components. One to model diffractive final states on the basis of the cluster hadronization model and a second component that addresses soft multiple interactions as multiple particle production in multiperipheral kinematics. We present much improved results for minimum-bias measurements at...
LHC forward (LHCf) is an experiment dedicated to afford the data for verifying and
improving the hadronic interaction models. The LHCf detectors were installed at +/-
140m from the ATLAS interaction point, covered the pesudorapidity range |η|>8.4
including zero degree. LHCf had several operations with different collision energies in p-p and p-Pb collisions.In this talk, we would like to...
A first measurement is presented of exclusive photoproduction of ρ0 mesons associated with leading neutrons at HERA. The data were taken with the H1 detector at a centre-of-mass energy of sqrt(s)=319 GeV and correspond to an integrated luminosity of 1.16 pb−1. The ρ mesons are reconstructed from their decays to charged pions, the neutrons are detected in the Forward...
We prove under some "reasonable" assumptions that the pion pion inelastic cross-section is larger than C exp(-C'sqrt{s} ln s)
We discuss central exclusive diffractive dihadron production in the reactions $pp \to pp \,\pi^{+} \pi^{-}$, $pp \to pp \,K^{+} K^{-}$ and $pp \to pp \,p \bar{p}$. The calculation is based on a tensor pomeron model and the amplitudes for the processes are formulated in an effective field-theoretic approach [1]. We include a purely diffractive dipion continuum, and the scalar and tensor...
The possibilities of the GenEx Monte Carlo generator will be shown. This tool is being developed by our group and is complementary to the existing MC generators. The generator is self-adapting to the provided matrix element and acceptance cuts. The modular structure of the code, designed for easy process implementation, will be shown. As an example, the exclusive production of pions (continuum...
Recent results for the total, elastic and inelastic hadronic cross-section from LHC experiments will be compared with predictions from one-channel eikonal mini-jet models, with QCD calculations from Durham and Telaviv groups, and with empirical models based on Regge-type parametrizations, adequately implemented with the very small $|t|$ behavior. The role of soft gluon resummation in the...
Rapidity gap survival factors are calculated in the Reggeon Field Theory
framework. In particular, the relative roles of eikonal and non-eikonal
absorptive corrections are investigated. Further, the impact parameter
dependence of rapidity gap suppression is studied, paying a special attention
to the effects of colour fluctuations in protons.