Neutron-skin effect in direct-photon and charged hadron-production in Pb+Pb collisions at the LHC

Abstract

A well-established observation in nuclear physics is that in neutron-rich spherical nuclei the distribution of neutrons extends farther than the distribution of protons. In this work, we scrutinize the influence of this so called neutron-skin effect on the centrality dependence of high-$p_{\mathrm{T}}$ direct-photon and charged-hadron production. We find that due to the estimated spatial dependence of the nuclear parton distribution functions, it will be demanding to unambiguously expose the neutron-skin effect with direct photons. However, when taking a ratio between the cross sections for negatively and positively charged high-$p_{\mathrm{T}}$ hadrons, even centrality-dependent nuclear-PDF effects cancel, making this observable a better handle on the neutron skin. Up to 20~\% effects can be expected for the most peripheral collisions.

7 pages, 3 figures, corresponds to the published version

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Cited by in corpus (12)

• The Angantyr model for Heavy-Ion Collisions in PYTHIA8
• Probing the neutron skin with ultrarelativistic isobaric collisions
• Progress in the Glauber model at collider energies
• The Present and Future of QCD
• Influence of the neutron-skin effect on nuclear isobar collisions at RHIC
• Constraints on the initial state of PbPb collisions via measurements of Z boson yields and azimuthal anisotropy at $\sqrt{s_{\mathrm{NN}}}=$ 5.02 TeV
• Spin-isospin correlated configurations in complex nuclei and neutron skin effect in W${}^{\pm }$ production in high-energy proton-lead collisions
• Shadowing in inelastic nucleon-nucleon cross section?
• Influence of nuclear structure in relativistic heavy-ion collisions
• The effect of neutron skin on inclusive prompt photon production in Pb~+~Pb collisions at the LHC
• Neutron-skin effect and centrality dependence of high-$p_{\mathrm{T}}$ observables in nuclear collisions
• Summary of Structure Functions and PDFs Working Group