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Yuri Kulchitsky

Publications and source records attributed to Yuri Kulchitsky.

3 recordsLinked to original sources

Study of KNO scaling in pp collisions at $\sqrt{s}$ from 0.9 to 13 TeV using results of the ATLAS at the LHC

The comparisons of the charged-particle multiplicity and the average transverse momentum distributions on the scaled multiplicity, KNO scale, using the results of the ATLAS collaboration at the LHC are presented. These distributions were measured in proton-proton collisions at centre-of-mass energies from 0.9 to 13 TeV for the absolute pseudorapidity region less than 2.5 and two samples of events with each charged-particle transverse momentum greater than 100 and 500 MeV, respectively. The shape evolution of the multiplicity distributions with a collision energy is studied in terms of KNO scaling variables. The charged-particle multiplicity distributions on the KNO scale have the similar shape and decrease with increasing collision energy. The KNO distributions tend to be independent of energy for the highest energies. The average transverse momentum distributions on the KNO scale have a similar shape and increase with increasing collision energy.

hep-ex

Study of energy response and resolution of the ATLAS Tile Calorimeter to hadrons of energies from 16 to 30 GeV

Three spare modules of the ATLAS Tile Calorimeter were exposed to test beams from the Super Proton Synchrotron accelerator at CERN in 2017. The measurements of the energy response and resolution of the detector to positive pions and kaons and protons with energy in the range 16 to 30 GeV are reported. The results have uncertainties of few percent. They were compared to the predictions of the Geant4-based simulation program used in ATLAS to estimate the response of the detector to proton-proton events at Large Hadron Collider. The determinations obtained using experimental and simulated data agree within the uncertainties.

physics.ins-det

Measurement of the underlying-event properties with the ATLAS detector

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 of Drell-Yan events in 1.1 1/fb of data collected at a center-of-mass energy of 7 TeV. In this new study the distributions of several topological event-shape variables based on charged particles are measured, both integrated and differential in the transverse momentum of the Drell-Yan lepton pair. These measurements are sensitive to the underlying-event as well as the onset of hard emissions. The results have been compared with the predictions of several state-of-the-art MC generators. The collaboration has also performed a first study of the number and transverse momentum sum of charged particles as a function of transverse momentum and azimuthal angle in a special data set taken with low beam currents at a center-of-mass energy of 13 TeV. The results are compared to predictions of several MC generators.

hep-ex