Role of multiparton interactions on J/ψ production in p+p collisions at LHC energies

Abstract

The production mechanism of quarkonia states in hadronic collisions is still to be understood by the scientific community. In high-multiplicity p þ p collisions, underlying event observables are of major interest. The multiparton interactions (MPIs) are underlying event observables, in which several interactions occur at the partonic level in a single p þ p event. This leads to dependence of particle production on event multiplicity. If the MPI occurs in a harder scale, there will be a correlation between the yield of quarkonia and total charged-particle multiplicity. The ALICE experiment at the LHC in p þ p collisions at ffiffi ffi s p ¼ 7 and 13 TeV has observed an approximate linear increase of relative J=ψ yield, ( dN J=ψ =dy hdN J=ψ =dyi ), with relative charged-particle multiplicity density, ( dN ch =dy hdN ch =dyi ). In our present work, we have performed a comprehensive study of the production of charmonia as a function of charged-particle multiplicity in p þ p collisions at LHC energies using the perturbative QCD-inspired multiparton interaction model, PYTHIA8 tune 4C, with and without the color reconnection scheme. A detailed multiplicity and energy-dependent study is performed to understand the effects of MPI on J=ψ production. The ratio of ψð2SÞ to J=ψ is also studied as a function of charged-particle multiplicity at LHC energies.

Criticality and factorization in the Heisenberg chain with Dzyaloshinskii-Moriya interaction

“…To proceed, we examine the relation between the quantum-information quantifier with QPTs in the presence of anisotropy term ∆. For axial regime ∆ 1 (∆ −1), the system effectively stays in the Néel (fer- romagnetic) phase [26]. In the following, we concentrate on the planar regime (|∆| < 1).…”

“…The effects induced by external electric and magnetic fields have been of particular interest since the magnetic state can be qualitatively different depending on the magnitude and direction of the external fields. This has led to interest in the study of QPTs at finite fields [25][26][27].…”

Dissociation of Quarkonium in Hot and Dense Media in an Anisotropic Plasma in the Nonrelativistic Quark Model

“…The production or suppression of quarkonia has been investigated either theoretically or experimentally in Refs. [2][3][4][5][6][7][8][9][10][11][12], and the disassociation temperature has been studied in Refs. [13][14][15][16][17].…”

Spin-1/2 XY chain magnetoelectric: Effect of zigzag geometry

“…[12,13] were further confirmed in Refs. [16,17]. The link between DM-terms and the quantum phase transitions of a generalized compass chain with staggered Dzyaloshinskii-Moriya interaction was also considered recently 18 .…”