Related papers: Hadron structure on the back of an envelope
Most of model considerations of the hidden nucleon strangeness, as well as some preliminary experimental evidence, led to the expectations of relatively sizeable strange vector form factors of the proton. For example, it seemed that the…
The spectra of strange hadrons are measured in proton-proton collisions, recorded by the CMS experiment at the CERN LHC, at centre-of-mass energies of 0.9 and 7 TeV. The K^0_s, Lambda, and Xi^- particles and their antiparticles are…
The strange magnetic moment of the proton is small in the chiral quark model, because of a near cancellation between the quantum fluctuations that involve kaons and $s$-quarks and loops that involve radiative transitions between strange…
Recent progress in lattice QCD calculations of nucleon structure will be presented. Calculations of nucleon matrix elements and form factors have long been difficult to reconcile with experiment, but with advances in both methodology and…
Several parameters characterizing the strangeness content of the nucleon have been calculated in the chiral constituent quark model with configuration mixing (\chiCQM_{config}) which is known to provide a satisfactory explanation of the…
The current $3.5\sigma$ discrepancy between experimental and Standard Model determinations of the anomalous magnetic moment of the muon $a_\mu=(g-2)/2$ can only be extended to the discovery $5\sigma$ regime through a reduction of both…
The modification of the Paschos-Wolfenstein relation is investigated when the charge symmetry violations of valence and sea quark distributions in the nucleon are taken into account. We also study qualitatively the impact of charge symmetry…
Nucleons (protons and neutrons) are the building blocks of atomic nuclei, and are responsible for more than 99\% of the visible matter in the universe. Despite decades of efforts in studying its internal structure, there are still a number…
We consider a simple model for the strangeness radius of the nucleon. The model is based on vector meson dominance (VMD) and $\omega - \phi$ mixing in addition to a kaon cloud contribution. We find that the VMD contribution is similar in…
Measurements of inclusive charged-hadron transverse-momentum and pseudorapidity distributions are presented for proton-proton collisions at sqrt(s) = 0.9 and 2.36 TeV. The data were collected with the CMS detector during the LHC…
The magnetic moment of the proton is calculated using a geometric unified theory. The geometry determines a generalized Pauli equation showing anomalous terms due to the triplet proton structure. The theoretical result gives a bare…
To date, the strongest indication of charge symmetry violation in parton distributions has been obtained by comparing the $F_2$ structure functions from CCFR neutrino data and NMC muon data. We show that in order to make precise tests of…
Background: Unravelling the role played by nonvalence flavors in baryons is crucial in deepening our comprehension of QCD. Strange quark, a component of the higher Fock states in baryons, is an appropriate tool to investigate…
Parity violation in elastic electron-nucleon scattering is studied with the basic goal of improving the understanding of electroweak hadronic structure with special emphasis on the strangeness content in the nucleon. Models for the…
Spin effects in exclusive and inclusive reactions provide an essential new dimension for testing QCD and unraveling hadron structure. Remarkable new experiments from SLAC, HERMES (DESY), and the Jefferson Laboratory present many challenges…
We report new measurements of the parity-violating asymmetry A_PV in elastic scattering of 3 GeV electrons off hydrogen and 4He targets with <theta_lab>~6.0 degrees. The 4He result is A_PV = (+6.40 +/- 0.23 (stat) +/- 0.12 (syst)) x10^-6.…
By determining the quark momentum fractions of the octet baryons from N_f=2+1 lattice simulations, we are able to predict the degree of charge symmetry violation in the parton distribution functions of the nucleon. This is of importance,…
We examine the possibility that one could measure partonic charge symmetry violation (CSV) by comparing neutrino or antineutrino production through charged-current reactions induced by electrons or positrons at a possible electron collider…
The consequences of the charge symmetry breaking effects of the mass difference between the up and down quarks and electromagnetic effects for searches for strangeness form factors in parity violating electron scattering from the proton are…
Study of the hadronic matrix elements can provide not only tests of the QCD sector of the Standard Model (in comparing with existing experiments) but also reliable low-energy hadronic quantities applicable to a wide range of…