English
Related papers

Related papers: Quark Model Calculations Of Symmetry Breaking in P…

200 papers

We derive simple relations between the polarized and unpolarized valence quark distributions in a light-cone SU(6) quark-spectator model for nucleons. The explicit x-dependent Wigner rotation effect for the light-flavor quarks is…

High Energy Physics - Phenomenology · Physics 2009-10-28 Bo-Qiang Ma

We use local quark-hadron duality to calculate the nucleon structure function as seen by neutrino and muon beams. Our result indicates a possible signal of charge symmetry violation at the parton level in the very large x region.

High Energy Physics - Phenomenology · Physics 2014-11-17 F. M. Steffens , K. Tsushima

We investigate an asymmetry in the angular distribution of hard elastic proton-neutron scattering with respect to 90deg center of mass scattering angle. We demonstrate that the magnitude of the angular asymmetry is related to the…

High Energy Physics - Phenomenology · Physics 2009-12-08 Carlos G. Granados , Misak M. Sargsian

The chiral quark model with a nonet of Goldstone bosons can yield an adequate description of the observed proton flavor and spin structure. In a previous publication we have compared the results of a SU(3) symmetric calculation with the…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. P. Cheng , Ling-Fong Li

The implications of Chiral Quark Model with SU(3) and axial U(1) symmetry breakings as well as configuration mixing generated by one gluon exchange forces ($\chi$QM$_{gcm}$) are discussed in context of proton flavor and spin structure as…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harleen Dahiya , Manmohan Gupta

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…

High Energy Physics - Phenomenology · Physics 2014-11-17 W. Melnitchouk

I review progress in calculating strange quark and antiquark distributions of the nucleon using the meson cloud model. This progress parallels that of the meson cloud model, which is now a useful theoretical basis for understanding symmetry…

Nuclear Theory · Physics 2015-05-18 A. I. Signal

Deep inelastic polarized and unpolarized structure functions for a free nucleon are obtained in a modified Center-of-Mass bag model, which includes the symmetry breaking effects from spin-dependent interactions. The quark distribution…

High Energy Physics - Phenomenology · Physics 2014-11-17 X. Song , J. S. McCarthy

We calculate the quark distribution function for 3He/3H in a relativistic quark model of nuclear structure which adequately reproduces the nucleon approximation, nuclear binding energies, and nuclear sizes for small nuclei. The results show…

Nuclear Theory · Physics 2012-08-27 C. J. Benesh , T. Goldman , G. J. Stephenson,

In this study, we performed calculations and analyses of the structure functions of polarized nucleons and light nuclei, specifically $^3$He and $^3$H, using second-order Feynman diagrams. Our investigation focused on two main aspects:…

High Energy Physics - Phenomenology · Physics 2023-09-08 Fatemeh Arbabifar , Shahin Atashbar Tehrani , Hamzeh Khanpour

The pion structure function is investigated in a simple model, where the pion and its constituent quark fields are coupled through the simplest pseudoscalar coupling. The imaginary part of the forward gamma* pi -> gamma* pi scattering…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. P. Lansberg , F. Bissey , J. R. Cudell , J. Cugnon , M. Jaminon , P. Stassart

The SU(3) symmetric chiral quark model, which describes interactions between quarks, gluons and the Goldstone bosons, explains reasonably well many aspects of the flavor and spin structure of the proton, except for the values of $f_3/f_8$…

High Energy Physics - Phenomenology · Physics 2008-11-26 X. Song , J. S. McCarthy , H. J. Weber

Using an SU(3)-flavour symmetry breaking expansion between the strange and light quark masses, we determine how this constrains the extrapolation of baryon octet matrix elements and form factors. In particular we can construct certain…

High Energy Physics - Lattice · Physics 2021-12-09 J. M. Bickerton , A. N. Cooke , R. Horsley , Y. Nakamura , H. Perlt , D. Pleiter , P. E. L. Rakow , G. Schierholz , H. Stüben , R. D. Young , J. M. Zanotti

This review paper presents the gluon, sea, and valence quark distributions of the pseudoscalar (PS) mesons. The calculations of the parton structure of PS mesons are performed using the Bethe-Salpeter equation-Nambu--Jona-Lasinio (BSE-NJL)…

High Energy Physics - Phenomenology · Physics 2023-03-06 Parada T. P. Hutauruk , Seung-il Nam

Pion valence, glue and sea distributions are calculated using a continuum approach to the two valence-body bound-state problem. Since the framework is symmetry preserving, physical features of the distributions are properly expressed. The…

Nuclear Theory · Physics 2020-03-18 Minghui Ding , Khepani Raya , Daniele Binosi , Lei Chang , C. D. Roberts , S. M. Schmidt

Understanding the differences between the distribution of quarks bound in protons and neutrons is key for constraining the mechanisms of SU(6) spin-flavor symmetry breaking in Quantum Chromodynamics (QCD). While vast amounts of proton…

High Energy Physics - Phenomenology · Physics 2021-04-16 E. P. Segarra , J. R. Pybus , F. Hauenstein , T. Kutz , D. Higinbotham , G. A. Miller , E. Piasetzky , A. Schmidt , M. Strikman , L. B. Weinstein , O. Hen

A physical model for parton densities in hadrons, based on Gaussian momentum fluctuations of partons and hadronic baryon-meson fluctuations, is presented. The model has previously been shown to describe proton structure function data, and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Johan Alwall

We extract the individual contributions from u and d quarks to the Dirac and Pauli form factors of the proton, after a critical examination of the available measurements of electromagnetic nucleon form factors. From this data we determine…

High Energy Physics - Phenomenology · Physics 2025-01-08 Markus Diehl , Peter Kroll

We systematically study quantum effect on chiral and $U_A(1)$ symmetry breaking under external electromagnetic fields in the frame of equal-time Wigner function formalism. We derive the transport and constraint equations for the quark…

High Energy Physics - Theory · Physics 2018-07-25 Xingyu Guo , Pengfei Zhuang

A formalism for the study of charge symmetry breaking (CSB) effects is discussed and used to analyze the effects of charge symmetry breaking on neutron beta decay. The effect of including CSB reduces the beta decay matrix element by an…

Nuclear Theory · Physics 2022-12-21 Jacob W. Crawford , Gerald A. Miller