656 research outputs found
Exploring light nuclei production at RHIC and LHC energies with A Multi-Phase Transport model and a coalescence afterburner
In heavy-ion collisions, understanding how light nuclei species are produced
can provide insight into the nature of hadronic interactions in extreme
conditions. It can also shed light on understanding the matter-antimatter
asymmetry and dark matter searches in astrophysical processes. To investigate
the production mechanism of light nuclei such as deuteron, triton, and
helium-3, we use a naive coalescence afterburner coupled to the well-known
A Multi-Phase Transport model" (AMPT). We focus on studying the production
of light nuclei in central Au+Au collisions at different center of mass
energies ( = 19.6, 39, and 200 GeV) and in Pb+Pb
collisions at = 2.76 TeV, at mid-rapidity. We generate
events with the string melting version of AMPT, and feed the information of the
nucleons with spatial and momentum conditions into the coalescence afterburner.
Our study reports differential and integrated yields in transverse momentum
() of the light nuclei in different center of mass energies. We
also estimate the coalescence parameters () as a function of
and collision energy for (anti-)deuterons, tritons and helium-3s for Au+Au and
Pb+Pb collisions, which are compared to other light nuclei production studies.
All results are compared with measurements from the STAR and ALICE experiments.Comment: 10 pages, 7 figure
Effect of various particlization scenarios on anisotropic flow and particle production using UrQMD hybrid model
We discuss the effect of various particlization scenarios available in the
hybrid ultrarelativistic quantum molecular dynamics (UrQMD) event generator on
different observables in non-central ( 5--9 ) Au + Au collisions in
the beam energy range 1A-158A GeV. Particlization models switch fluid dynamic
description to the transport description using various hypersurface criteria.
In addition to particlization models, various equations-of-state (EoS) provided
by the UrQMD hybrid model were employed. The observables examined in this paper
include the excitation function of anisotropic coefficients such as directed
() and elliptic flow (), particle ratios of the species, and the
shape of net-proton rapidity spectra at mid-rapidity. The results obtained here
can help predict and compare the measurements provided by future experiments at
the Facility for Antiproton and Ion Research (FAIR) and the Nuclotron-based Ion
Collider fAcility (NICA) once the data becomes available. We also study the
most suitable combination of the particlization model and EoS, which best
describes the experimental measurements.Comment: 11 pages, 8 figure
Dynamics of Hot QCD Matter -- Current Status and Developments
The discovery and characterization of hot and dense QCD matter, known as
Quark Gluon Plasma (QGP), remains the most international collaborative effort
and synergy between theorists and experimentalists in modern nuclear physics to
date. The experimentalists around the world not only collect an unprecedented
amount of data in heavy-ion collisions, at Relativistic Heavy Ion Collider
(RHIC), at Brookhaven National Laboratory (BNL) in New York, USA, and the Large
Hadron Collider (LHC), at CERN in Geneva, Switzerland but also analyze these
data to unravel the mystery of this new phase of matter that filled a few
microseconds old universe, just after the Big Bang. In the meantime,
advancements in theoretical works and computing capability extend our wisdom
about the hot-dense QCD matter and its dynamics through mathematical equations.
The exchange of ideas between experimentalists and theoreticians is crucial for
the progress of our knowledge. The motivation of this first conference named
"HOT QCD Matter 2022" is to bring the community together to have a discourse on
this topic. In this article, there are 36 sections discussing various topics in
the field of relativistic heavy-ion collisions and related phenomena that cover
a snapshot of the current experimental observations and theoretical progress.
This article begins with the theoretical overview of relativistic
spin-hydrodynamics in the presence of the external magnetic field, followed by
the Lattice QCD results on heavy quarks in QGP, and finally, it ends with an
overview of experiment results.Comment: Compilation of the contributions (148 pages) as presented in the `Hot
QCD Matter 2022 conference', held from May 12 to 14, 2022, jointly organized
by IIT Goa & Goa University, Goa, Indi
Measurements of heavy-flavor production as a function of multiplicity with ALICE at the LHC
In this contribution, the production of heavy-flavor hadrons as a function of multiplicity, via the study of the D-meson and heavy-flavor hadron decay leptons self-normalized yields in pp collisions at the center of mass energy TeV is discussed. Comparisons are made with similar measurements of J/ at TeV and various model calculations. The and yield ratios in different multiplicity intervals in pp collisions at TeV are also reported. In addition, the ALICE measurement of production in p-Pb collisions at = 5.02 TeV down to transverse momentum () = 0 GeV/ is presented. Finally, the nuclear modification factor is shown for open charm hadrons at TeV in p-Pb collisions. Finally, measurements of the elliptic flow of heavy-flavor hadron decay leptons in p-Pb systems are presented, which hint towards a possible collective behaviour in high multiplicity p-Pb collisions.In this contribution, the production of heavy-flavor hadrons as a function of multiplicity, via the study of the D-meson and heavy-flavor hadron decay leptons self-normalized yields in pp collisions at the center of mass energy TeV is discussed. Comparisons are made with similar measurements of J/ at TeV and various model calculations. The and yield ratios in different multiplicity intervals in pp collisions at TeV are also reported. In addition, the ALICE measurement of production in p-Pb collisions at = 5.02 TeV down to transverse momentum () = 0 GeV/ is presented. Finally, the nuclear modification factor is shown for open charm hadrons at TeV in p-Pb collisions. Finally, measurements of the elliptic flow of heavy-flavor hadron decay leptons in p-Pb systems are presented, which hint towards a possible collective behaviour in high multiplicity p-Pb collisions
Measurement of -meson production as a function of charged-particle multiplicity in proton--proton collisions at TeV with ALICE at the LHC
Heavy quarks (charm and beauty) are produced in hard-scattering processes and the study of their production in proton--proton (pp) collisions is an important test for calculations based on perturbative Quantum Chromodynamics (pQCD). Heavy-flavor production as a function of charged-particle multiplicity provides insight into the processes occurring at the partonic level and the interplay between the hard and soft particle production mechanisms in pp collisions.
In this contribution, measurements of open heavy-flavor production as a function of multiplicity, via the study of the -meson self-normalized yields in pp collisions at the center-of-mass energy of TeV is presented. The -meson self-normalized yield is found to increase stronger than linearly with increasing charged-particle multiplicity. The measurements are compared to theoretical model calculations, and with the results at TeV.Heavy quarks (charm and beauty) are produced in hard-scattering processes and the study of their production in proton--proton (pp) collisions is an important test for calculations based on perturbative Quantum Chromodynamics (pQCD). Heavy-flavor production as a function of charged-particle multiplicity provides insight into the processes occurring at the partonic level and the interplay between the hard and soft particle production mechanisms in pp collisions. In this contribution, measurements of open heavy-flavor production as a function of multiplicity, via the study of the -meson self-normalized yields in pp collisions at the center-of-mass energy of TeV is presented. The -meson self-normalized yield is found to increase stronger than linearly with increasing charged-particle multiplicity. The measurements are compared to theoretical model calculations, and with the results at TeV
Pseudorapidity densities of charged particles with transverse momentum thresholds in pp collisions at √ s = 5.02 and 13 TeV
The pseudorapidity density of charged particles with minimum transverse momentum (pT) thresholds of 0.15, 0.5, 1, and
2 GeV/c is measured in pp collisions at the center of mass energies of √s=5.02 and 13 TeV with the ALICE detector. The study is carried out for inelastic collisions with at least one primary charged particle having a pseudorapidity (η) within 0.8pT larger than the corresponding threshold. In addition, measurements without pT-thresholds are performed for inelastic and nonsingle-diffractive events as well as for inelastic events with at least one charged particle having
|η|2GeV/c), highlighting the importance of such measurements for tuning event generators. The new measurements agree within uncertainties with results from the ATLAS and CMS experiments obtained at √s=13TeV.
- …