Impact of LHC vector boson production in heavy ion collisions on strange PDFs

• Autor: Kusina, A. ; Ježo, T. ; Clark, D. B. ; Duwentäster, P. ; Godat, E. ; Hobbs, T. J. ; Kent, J. ; Klasen, M. ; Kovařík, K. ; Lyonnet, F. ; Muzakka, K. F. ; Olness, F. I. ; Schienbein, I. ; Yu, J. Y.
• Assuntos: Astronomy ; Astrophysics and Cosmology ; Collisions (Nuclear physics) ; Comparative analysis ; Distribution (Probability theory) ; Distribution functions ; Elementary Particles ; Flavor (particle physics) ; Hadrons ; Heavy Ions ; High Energy Physics - Phenomenology ; Inelastic scattering ; Ionic collisions ; Large Hadron Collider ; LHC heavy ion physics ; Measurement Science and Instrumentation ; Neutrinos ; Nuclear Energy ; nuclear parton distribution function ; Nuclear Physics ; NUCLEAR PHYSICS AND RADIATION PHYSICS ; Nuclei (nuclear physics) ; Partons ; Physics ; Physics and Astronomy ; PHYSICS OF ELEMENTARY PARTICLES AND FIELDS ; Protons ; quantum chromodynamics ; Quantum Field Theories ; Quantum Field Theory ; Quarks ; Regular Article - Theoretical Physics ; String Theory
• É parte de: The European physical journal. C, Particles and fields, 2020-10, Vol.80 (10), p.1-21, Article 968
• Notas: JLab EIC Center Fellowship; SC0010129; 396021762-TRR-257; 273811115-SFB-1225
  German Research Foundation (DFG)
  USDOE Office of Science (SC), High Energy Physics (HEP)
  
• Descrição: The extraction of the strange quark parton distribution function (PDF) poses a long-standing puzzle. Measurements from neutrino-nucleus deep inelastic scattering (DIS) experiments suggest the strange quark is suppressed compared to the light sea quarks, while recent studies of W ± / Z boson production at the LHC imply a larger strange component at small  x values. As the parton flavor determination in the proton depends on nuclear corrections, e.g. from heavy-target DIS, LHC heavy ion measurements can provide a distinct perspective to help clarify this situation. In this investigation we extend the nCTEQ15 nPDFs to study the impact of the LHC proton-lead W ± / Z production data on both the flavor differentiation and nuclear corrections. This complementary data set provides new insights on both the LHC W ± / Z proton analyses and the neutrino-nucleus DIS data. We identify these new nPDFs as nCTEQ15WZ . Our calculations are performed using a new implementation of the nCTEQ code ( nCTEQ++ ) based on C++ which enables us to easily interface to external programs such as HOPPET, APPLgrid and MCFM. Our results indicate that, as suggested by the proton data, the small  x nuclear strange sea appears larger than previously expected, even when the normalization of the W ± / Z data is accommodated in the fit. Extending the nCTEQ15 analysis to include LHC W ± / Z data represents an important step as we advance toward the next generation of nPDFs.
  
• Editor: Berlin/Heidelberg: Springer Berlin Heidelberg
  
• Idioma: Inglês