Find in Library
Search millions of books, articles, and more
Indexed Open Access Databases
Impact of LHC vector boson production in heavy ion collisions on strange PDFs
oleh: A. Kusina, T. Ježo, D. B. Clark, P. Duwentäster, E. Godat, T. J. Hobbs, J. Kent, M. Klasen, K. Kovařík, F. Lyonnet, K. F. Muzakka, F. I. Olness, I. Schienbein, J. Y. Yu
| Format: | Article |
|---|---|
| Diterbitkan: | SpringerOpen 2020-10-01 |
Deskripsi
Abstract 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 $$W^\pm /Z$$ 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 $$W^\pm /Z$$ W ± / Z production data on both the flavor differentiation and nuclear corrections. This complementary data set provides new insights on both the LHC $$W^\pm /Z$$ 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 $$W^{\pm }/Z$$ W ± / Z data is accommodated in the fit. Extending the nCTEQ15 analysis to include LHC $$W^\pm /Z$$ W ± / Z data represents an important step as we advance toward the next generation of nPDFs.