相关论文: The s-s(bar) asymmetry in nucleon and "NuTeV anoma…
We compute the $s-\bar s$ asymmetry in the proton in chiral effective theory, using phenomenological constraints based upon existing data. Unlike previous meson cloud model calculations, which accounted for kaon loop contributions with…
Asymmetries in the quark momentum distributions in the proton reveal fundamental aspects of strong interaction physics. Differences between u-bar and d-bar quarks in the proton sea provide insight into the dynamics of the pion cloud around…
Recent deep inelastic scattering and Drell-Yan experiments have revealed a surprisingly large asymmetry between the up and down sea quark distributions in the nucleon. The current status of the flavor asymmetry of the nucleon sea is…
The nucleon strange and anti-strange distribution asymmetry is an important issue in the study of the nucleon structure. In this work, we show that the heavy quark recombination processes from a perturbative QCD picture can give a sizable…
Recent deep inelastic scattering and Drell-Yan experiments have revealed a surprisingly large asymmetry between the up and down sea quark distributions in the nucleon. In this article, we review the status of the flavor asymmetry of the…
Based on quantum fluctuations in momentum and of the proton into meson-baryon pairs, we develop a physical model for the non-perturbative x-shape of parton density functions in the proton. The model describes the proton structure function…
The difference between the $\Lambda$ and $\bar \Lambda$ longitudinal spin transfers in the semi-inclusive deep inelastic scattering process is intensively studied. The study is performed in the current fragmentation region, by considering…
We discuss the phenomenology of strange-quark dynamics in the nucleon, based on experimental and theoretical results for electroweak form factors and for parton densities. In particular, we construct a model for the generalized parton…
Contributions from physics beyond the Standard Model, strange quarks in the nucleon, and nuclear structure effects to the left-right asymmetry measured in parity-violating (PV) electron scattering from $\nuc{12}{C}$ and the proton are…
The difference between the strange and antistrange quark distributions, $\delta s(x)=s(x)-\sbar(x)$, and the combination of light quark sea and strange quark sea, $\Delta (x)=\dbar(x)+\ubar(x)-s(x)-\sbar(x)$, are originated from…
A new global QCD analysis of DIS data is presented. The \nu Fe and \bar{\nu}Fe differential cross-section data are included to constrain the strange component of the nucleon sea. As a result we found a hard strangeness at high-x and some…
We discuss whether the NuTeV anomaly can be explained, compatibly with all other data, by QCD effects (maybe, if the strange sea is asymmetric, or there is a tiny violation of isospin), new physics in propagators or couplings of the vector…
The discovery of neutrino masses has provided strong hints in favor of the possibility that B-L symmetry is an intimate feature of physics beyond the standard model. I discuss how important information about this symmetry as well as other…
The NuTeV Collaboration reported a value of $\sin^{2}\theta_{w}$ measured in neutrino-nucleon deep inelastic scattering, and found that the value is three standard deviations from the standard model prediction. This result is obtained under…
The strange sea quarks distributions of nucleons obtained by two global analyses based on available structure function data of muon and neutrino deep inelastic scatterings are different from the strange sea quark distribution measured by…
Modern nucleon-nucleon (NN) potentials, which accurately fit the nucleon-nucleon scattering phase shifts, contain terms which break isospin symmetry. The effects of these symmetry violating terms on the bulk properties of nuclear matter are…
It is now widely recognized that a key to unravel the nonperturbative chiral-dynamics of QCD hidden in the deep-inelastic-scattering observables is the flavor structure of sea-quark distributions in the nucleon. We analyze the flavor…
We present a general analysis of the spin transfer for $\Lambda$ and $\bar{\Lambda}$ production in deep-inelastic scattering of polarized charged leptons on the nucleon, and find that the pattern of different behaviors of $\Lambda$ and…
We review recent experimental and theoretical developments in the study of the sea quark structure of the proton. In the light quark sector, we analyse the recent pp and pD Drell-Yan data from the E866/NuSea experiment at Fermilab, and…
By comparing structure functions measured in neutrino and charged lepton deep inelastic scattering, one can test the validity of parton charge symmetry. New experiments allow us to make such tests, which set rather tight upper limits on…