We study the proton and the Roper resonance together with the meson cloud model, by constructing a Hamiltonian matrix and solving the eigenvalue equation. The proton sea quark flavour asymmetry and some properties of ...We study the proton and the Roper resonance together with the meson cloud model, by constructing a Hamiltonian matrix and solving the eigenvalue equation. The proton sea quark flavour asymmetry and some properties of the Roper resonance are thus reproduced in one scheme.展开更多
By means of two typical kinds of quark energy loss parametrization and the nuclear parton distribu-tions determined only with lepton-nuclear deep inelastic scattering experimental data, a leading order analysis is per...By means of two typical kinds of quark energy loss parametrization and the nuclear parton distribu-tions determined only with lepton-nuclear deep inelastic scattering experimental data, a leading order analysis is performed on the proton-induced Drell-Yan differential cross section ratios of tungsten versus deuterium as a function of the quark momentum fraction in the beam proton and target nuclei. It is found that the theoretical results with quark energy loss are in good agreement with the experimental data. The quark energy loss effect produces approximately 3% to 11% suppression on the Drell-Yan differential cross section ratios RW/D in the range 0.05 ≤ x2 ≤ 0.3. The application of nuclear Drell-Yan data with heavy targets is remarkably subject to difficulty in the constraint of the nuclear sea quark distribution.展开更多
Both the PHENIX and STAR experiments at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory are running polarized proton-proton collisions at √s = 200 and 500 GeV. The main goal of the RHIC...Both the PHENIX and STAR experiments at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory are running polarized proton-proton collisions at √s = 200 and 500 GeV. The main goal of the RHIC spin physics program is to gain deeper insight into the spin structure of the nucleon. We will give an overview of recent spin results from RHIC, particularly the study of gluon polarization via jet/hadron production and sea quark polarization via W boson production in longitudinally polarized proton-proton collisions.展开更多
基金Supported by Liaoning Education Office Scientific Research Project(2008288)SRF for ROCS, SEM and National NaturalScience Foundation of China (10705017)
文摘We study the proton and the Roper resonance together with the meson cloud model, by constructing a Hamiltonian matrix and solving the eigenvalue equation. The proton sea quark flavour asymmetry and some properties of the Roper resonance are thus reproduced in one scheme.
基金Supported by National Natural Science Foundation of China(10575028)Natural Science Foundation of Hebei Province(A2008000137)
文摘By means of two typical kinds of quark energy loss parametrization and the nuclear parton distribu-tions determined only with lepton-nuclear deep inelastic scattering experimental data, a leading order analysis is performed on the proton-induced Drell-Yan differential cross section ratios of tungsten versus deuterium as a function of the quark momentum fraction in the beam proton and target nuclei. It is found that the theoretical results with quark energy loss are in good agreement with the experimental data. The quark energy loss effect produces approximately 3% to 11% suppression on the Drell-Yan differential cross section ratios RW/D in the range 0.05 ≤ x2 ≤ 0.3. The application of nuclear Drell-Yan data with heavy targets is remarkably subject to difficulty in the constraint of the nuclear sea quark distribution.
基金Acknowledgements The work was supported by the National Natural Science Foundation of China, China, under Grant Nos. 11175106 and 11222551, and the Natural Science Foundation of Shandong Province, China, under Grant No. ZR2013JQ001.
文摘Both the PHENIX and STAR experiments at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory are running polarized proton-proton collisions at √s = 200 and 500 GeV. The main goal of the RHIC spin physics program is to gain deeper insight into the spin structure of the nucleon. We will give an overview of recent spin results from RHIC, particularly the study of gluon polarization via jet/hadron production and sea quark polarization via W boson production in longitudinally polarized proton-proton collisions.