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Related papers: Flavor and Spin Structure of $\Lambda$-Baryon at L…

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The flavor and spin structure for the quark distributions of the $\Lambda$-baryon is studied in a perturbative QCD (pQCD) analysis and in the SU(6) quark-diquark model, and then applied to calculate the $\Lambda$-polarization of…

High Energy Physics - Phenomenology · Physics 2009-10-31 Bo-Qiang Ma , Ivan Schmidt , Jian-Jun Yang

The quark flavor and spin distributions in octet baryons are calculated both in the SU(6) quark spectator diquark model and in a perturbative QCD (pQCD) based model. It is shown that the $\Lambda$ has the most significant difference in…

High Energy Physics - Phenomenology · Physics 2009-10-31 Bo-Qiang Ma , Ivan Schmidt , Jian-Jun Yang

SU(3) symmetry relations between the octet baryons are introduced in order to connect both the unpolarized and polarized quark distributions of the octet baryons with those of the nucleon. Two different parametrizations of the nucleon quark…

High Energy Physics - Phenomenology · Physics 2009-11-07 Bo-Qiang Ma , Ivan Schmidt , Jacques Soffer , Jian-Jun Yang

We check the $u$ and $d$ quark contributions to the spin content of the $\Lambda$ by means of the $q\to\Lambda$ fragmentation and find that the $u$ and $d$ quarks of the $\Lambda$ are likely positively polarized. The parton distributions in…

High Energy Physics - Phenomenology · Physics 2011-02-01 Jian-Jun Yang

It is shown that neutrino and antineutrino deep inelastic scattering of unpolarized and polarized $\Lambda$ and $\bar{\Lambda}$ productions, can provide a clean separation of unpolarized and polarized fragmentation functions of a quark into…

High Energy Physics - Phenomenology · Physics 2009-10-31 Bo-Qiang Ma , Jacques Soffer

We discuss the quark parton structure of the $\Lambda$ baryon and the fragmentation of quarks into $\Lambda$ baryons. We show that the hyperfine interaction, responsible for the $\Delta$-$N$ and $\Sigma^0$-$\Lambda$ mass splittings, leads…

High Energy Physics - Phenomenology · Physics 2010-02-17 C. Boros , J. T. Londergan , A. W. Thomas

Spin dependent fragmentation functions for heavy flavor quarks to fragment into heavy baryons are calculated in a quark-diquark model. The production of intermediate spin 1/2 and 3/2 excited states is explicity included. $\Lambda_b$ ,…

High Energy Physics - Phenomenology · Physics 2009-10-31 Gary R. Goldstein

Spin asymmetries of semi-inclusive cross sections for the production of positively and negatively charged hadrons have been measured in deep-inelastic scattering of polarized positrons on polarized hydrogen and 3He targets, in the kinematic…

High Energy Physics - Experiment · Physics 2008-11-26 K. Ackerstaff , The HERMES Collaboration

The flavor and helicity distributions of the $\Lambda$ and $\bar{\Lambda}$ hyperons for both valence and sea quarks are calculated in a perturbative QCD (pQCD) based model. We relate these quark distributions to the fragmentation functions…

High Energy Physics - Phenomenology · Physics 2011-09-13 Bo-Qiang Ma , Ivan Schmidt , Jacques Soffer , Jian-Jun Yang

The perturbative QCD calculation of heavy quark fragmentation into a heavy meson is extended to predict fragmentation into heavy flavor baryons. This is accomplished by implementing the quark-diquark model of the baryons. Several diquark…

High Energy Physics - Phenomenology · Physics 2007-05-23 Anatoly D. Adamov , Gary R. Goldstein

A perturbative QCD calculation of heavy flavor quark fragmentation into heavy flavor baryons is developed along the lines of corresponding heavy meson models. The non-perturbative formation of the baryon is accomplished by implementing the…

High Energy Physics - Phenomenology · Physics 2009-10-30 Anatoly D. Adamov , Gary R. Goldstein

The recent progress in the investigations on the quark structure of the $\Lambda$ and $\Sigma$ baryons are reviewed. It is shown that the quark structure of $\Lambda$ and $\Sigma$ hyperons can provide a new domain to test various theories…

High Energy Physics - Phenomenology · Physics 2009-10-31 Bo-Qiang Ma

We study $\Lambda$ baryons of spin-parity $\frac{1}{2}^{\pm}$ with either a strange or charm valence quark in full 2+1 flavor lattice QCD. Multiple $SU(3)$ singlet and octet operators are employed to generate the desired single baryon…

High Energy Physics - Lattice · Physics 2017-01-09 Philipp Gubler , Toru T. Takahashi , Makoto Oka

The spin-flavor structure of large N baryons is described in the 1/N expansion of QCD using quark operators. The complete set of quark operator identities is obtained, and used to derive an operator reduction rule which simplifies the 1/N…

High Energy Physics - Phenomenology · Physics 2008-11-26 Roger Dashen , Elizabeth Jenkins , Aneesh V. Manohar

Treating baryons as quark + interacting-diquark bound states, a symmetry-preserving formulation of a vector$\,\times\,$vector contact interaction (SCI) is used to deliver an extensive, coherent set of predictions for $\Lambda, \Sigma^0$…

High Energy Physics - Phenomenology · Physics 2025-09-09 Yang Yu , Peng Cheng , Hui-Yu Xing , Daniele Binosi , Craig D. Roberts

By assuming that there is no significant intrinsic polarization of the gluon, we have computed the polarized quark contributions to the proton's spin under SU(3) flavor symmetry breaking for the polarized sea and have performed a global…

High Energy Physics - Phenomenology · Physics 2009-10-28 Chung-Yi Wu

Using a simple quark-diquark model, we extract a set of unpolarized and polarized fragmentation functions for the $\Lambda$ based on the available unpolarized $\Lambda$ production data in $e^+ e ^- $ annihilation. It is found that there is…

High Energy Physics - Phenomenology · Physics 2016-09-06 Jian-Jun Yang

The $1/N_c$-expansion of QCD suggests large flavor asymmetries of the polarized antiquark distributions in the nucleon. This is confirmed by model calculations in the large-$N_c$ limit (chiral quark-soliton model), which give sizable…

High Energy Physics - Phenomenology · Physics 2011-09-13 B. Dressler , K. Goeke , M. V. Polyakov , C. Weiss

Spin dependent fragmentation functions for heavy flavor quarks to fragment into heavy baryons are calculated in a quark-diquark model. The production of intermediate spin 1/2 and 3/2 excited states is explicity included. The resulting…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. Adamov , Gary R. Goldstein

The internal spin structure of the Lambda is of special importance for the understanding of the spin structure of hadrons in general. The comparison between the nucleon and Lambda allows for a test of the relevant flavour-symmetry breaking…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , R. Horsley , D. Pleiter , P. E. L. Rakow , S. Schaefer , A. Schäfer , G. Schierholz
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