0617336 - FZÚ 2025 RIV US eng J - Journal Article
Abazov, V. M. - Abbott, B. - Acharya, B.S. - Kupčo, Alexander - Lokajíček, Miloš … Total 367 authors
Up and down quark structure of the proton.
Physical Review D. Roč. 110, č. 9 (2024), č. článku L091101. ISSN 2470-0010. E-ISSN 2470-0029
Research Infrastructure: Fermilab-CZ III - 90261
Institutional support: RVO:68378271
Keywords : anti-p p: colliding beams * parton: distribution function * angular distribution: asymmetry
OECD category: Particles and field physics
Impact factor: 4.6, year: 2023 ; AIS: 1.057, rok: 2023
Method of publishing: Open access
DOI: https://doi.org/10.1103/PhysRevD.110.L091101

We measure proton structure parameters sensitive primarily to valence quarks using 8.6 fb−1−1 of data collected by the D0 detector in s=1.96s ​=1.96 TeV ppˉppˉ​ collisions at the Fermilab Tevatron. We exploit the property of the forward-backward asymmetry in dilepton events to be factorized in to distinct structure parameters and electroweak quark-level asymmetries. Contributions to the asymmetry from ss, cc and bb quarks, as well as from uu and dd quarks, are suppressed allowing valence uu and dd quarks to be separately determined. We find and uu to dd quark ratio near the peak values in the quark density distributions that is smaller than predictions from modern parton distribution functions.
Permanent Link: https://hdl.handle.net/11104/0364266