English
Related papers

Related papers: Radiatively Generated Isospin Violations in the Nu…

200 papers

Next-to-leading order QCD corrections, order 1 GeV mass corrections and the role of a strangeness asymmetry and isospin violation in the x dependence of the parton distribution functions are evaluated in the context of the neutrino-nucleon…

High Energy Physics - Phenomenology · Physics 2009-11-10 M. H. Reno

At a low resolution scale with $Q^2={\mu}^2$ corresponding to the nucleon bound state; deep inelastic unpolarized structure functions $F_1(x,{\mu}^2)$ and $F_2(x,{\mu}^2)$ are derived with correct support using the symmetric part of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 N. Barik , R. N. Mishra

We point out that charge symmetry violation in both the valence and sea quark distributions of the nucleon has a non-perturbative source. We calculate this non-perturbative charge symmetry violation using the meson cloud model, which has…

High Energy Physics - Phenomenology · Physics 2009-10-31 Fu-Guang Cao , A. I. Signal

Nuclear parton distributions are studied in a parton model with rescaling and recombination mechanisms. Parton x distributions are first calculated at Q^2=1 GeV^2 by the model, and they are evolved to larger Q^2 in order to be compared with…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Kumano , K. Umekawa

For the first time, charge symmetry breaking terms in parton distribution functions have been included in a global fit to high energy data. We review the results obtained for both valence and sea quark charge symmetry violation, and we…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. T. Londergan , A. W. Thomas

We present the polarized parton distribution functions from a QCD analysis of the worldwide polarized deep inelastic scattering data, based on the dynamical parton distribution model. All the sea quarks and gluons are dynamically generated…

High Energy Physics - Phenomenology · Physics 2022-11-23 Chengdong Han , Gang Xie , Rong Wang , Xurong Chen

Radiative corrections to the parity-violating asymmetry measured in elastic electron-proton scattering are analyzed in the framework of the Standard Model. We include the complete set of one-loop contributions to one quark current…

Nuclear Theory · Physics 2007-05-23 S. Barkanova , A. Aleksejevs , P. G. Blunden

By studying the Paschos-Wolfenstein (PW) ratio of deep inelastic $\nu{\rm Fe}$ and $\bar \nu{\rm Fe}$ scattering cross sections, we show that it should be possible to explain the NuTeV $\sin ^2 \theta_{\rm W}$ anomaly with quite…

High Energy Physics - Phenomenology · Physics 2009-11-11 K. J. Eskola , H. Paukkunen

We have made next to leading order QCD fit to the deep inelastic spin asymmetries on nucleons and we determined polarised quark and gluon densities. The functional form for such distributions was inspired by the Martin, Roberts and Stirling…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stanislaw Tatur , Jan Bartelski , Miroslaw Kurzela

An updated next-to-leading order (NLO) QCD analysis of the spin asymmetries A_1^N(x,Q^2) and parton distributions delta f(x,Q^2) in longitudinally polarized deep-inelastic lepton-nucleon scattering is presented within the framework of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Stratmann

We point out that perturbative evolution in QCD at three loops generates a strange-antistrange asymmetry s(x)-sbar(x) in the nucleon's sea just from the fact that the nucleon has non-vanishing up and down quark valence densities. The…

High Energy Physics - Phenomenology · Physics 2009-11-10 Stefano Catani , Daniel de Florian , German Rodrigo , Werner Vogelsang

Although the distributions of sea quarks and antiquarks generated by leading-twist QCD evolution through gluon splitting $g \rightarrow \bar q q$ are necessarily CP symmetric, the distributions of nonvalence quarks and antiquarks which are…

High Energy Physics - Phenomenology · Physics 2009-09-11 S. J. Brodsky , B. -Q. Ma

A quantitative understanding of isospin violation is an increasingly important ingredient for the extraction of the nucleon's strange vector form factors from experimental data. We calculate the isospin violating electric and magnetic form…

Nuclear Theory · Physics 2008-11-26 Bastian Kubis , Randy Lewis

The strangeness degrees of freedom in the parton structure of the nucleon are explored in the global analysis framework, using the new CTEQ6.5 implementation of the general mass perturbative QCD formalism of Collins. We systematically…

High Energy Physics - Phenomenology · Physics 2014-11-18 H. L. Lai , P. Nadolsky , J. Pumplin , D. Stump , W. K. Tung , C. -P. Yuan

The origin of the radiatively induced Lorentz and CPT violations, in perturbative evaluations, of an extended version of QED, is investigated. Using a very general calculational method, concerning the manipulations and calculations…

High Energy Physics - Theory · Physics 2011-07-19 O. A. Battistel , G. Dallabona

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…

High Energy Physics - Phenomenology · Physics 2007-05-23 Johan Alwall , Gunnar Ingelman

A neutron or proton excess in nuclei leads to an isovector-vector mean-field which, through its coupling to the quarks in a bound nucleon, implies a shift in the quark distributions with respect to the Bjorken scaling variable. We show that…

Nuclear Theory · Physics 2009-07-22 I. C. Cloët , W. Bentz , A. W. Thomas

The asymptotic collinear factorisation theorem, which holds for diffractive deep-inelastic scattering, has important modifications in the sub-asymptotic HERA regime. We use perturbative QCD to quantify these modifications. The diffractive…

High Energy Physics - Phenomenology · Physics 2010-03-25 A. D. Martin , M. G. Ryskin , G. Watt

Traditionally isospin violation (charge symmetry breaking and charge dependence) has been modeled by the exchange of mesons between two nucleons. Sources of isospin violation in these models include meson mass differences, meson mixing (of…

Nuclear Theory · Physics 2007-05-23 S. A. Coon

Isospin symmetry is well fulfilled in the QCD vacuum, as evidenced by small mass differences of isospin partners and suppressed isospin-violating decays. Recently, the NA61/SHINE collaboration reported an unexpectedly large…

Nuclear Theory · Physics 2025-10-01 Francesco Giacosa , Martin Rohrmoser