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Related papers: Strange quark content of the nucleon

200 papers

We present a QCD calculation of the $u$, $d$ and $s$ scalar quark contents of nucleons based on $47$ lattice ensembles with $N_f = 2+1$ dynamical sea quarks, $5$ lattice spacings down to $0.054\,\text{fm}$, lattice sizes up to…

High Energy Physics - Lattice · Physics 2016-05-12 S. Durr , Z. Fodor , C. Hoelbling , S. D. Katz , S. Krieg , L. Lellouch , T. Lippert , T. Metivet , A. Portelli , K. K. Szabo , C. Torrero , B. C. Toth , L. Varnhorst

We determine the nucleon axial, scalar and tensor charges at the continuum limit by analyzing three $N_f=2+1+1$ twisted mass fermion ensembles with all quark masses tuned to approximately their physical values. We include all contributions…

High Energy Physics - Lattice · Physics 2025-02-11 Constantia Alexandrou , Simone Bacchio , Jacob Finkenrath , Christos Iona , Giannis Koutsou , Yan Li , Gregoris Spanoudes

The low-energy neutron-Sigma^- interactions determine, in part, the role of the strange quark in dense matter, such as that found in astrophysical environments. The scattering phase shifts for this system are obtained from a numerical…

High Energy Physics - Lattice · Physics 2013-05-30 S. R. Beane , E. Chang , S. D. Cohen , W. Detmold , H. -W. Lin , T. C. Luu , K. Orginos , A. Parreno , M. J. Savage , A. Walker-Loud

The simplest models might describe the nucleon as 3 light quarks, but this description would be incomplete without inclusion of the sea of glue and q-qbar pairs which binds it. Early indications of a particularly large contribution from…

Nuclear Experiment · Physics 2011-10-18 Kent Paschke , Anthony Thomas , Robert Michaels , David Armstrong

We present the final analysis of the light and strange hadron spectra from a full QCD lattice simulation with two degenerate dynamical sea quark flavours at $\beta = 5.6$ on a $16^3 \times 32$ lattice. Four sets of sea quark masses…

High Energy Physics - Lattice · Physics 2016-08-25 N. Eicker , U. Glässner , S. Güsken , H. Hoeber , P. Lacock , Th. Lippert , K. Schilling , A. Spitz , Th. Struckmann , P. Ueberholz , J. Viehoff

The strange properties of the nucleon are investigated within the framework of the SU(3) chiral quark-soliton model assuming isospin symmetry and applying the symmetry conserving SU(3) quantization. We present the form factors…

High Energy Physics - Phenomenology · Physics 2014-11-17 António Silva , Hyun-Chul Kim , Klaus Goeke

The nucleon form factors provide fundamental knowledge about the strong interaction. We review the flavor composition of the nucleon form factors and focus on an analysis of the possible impact of the s-quark contribution. A future…

Nuclear Experiment · Physics 2020-01-08 Bogdan Wojtsekhowski

The QCDSF/UKQCD collaboration has an ongoing program to calculate nucleon matrix elements with two flavours of dynamical O(a) improved Wilson fermions. Here we present recent results on the electromagnetic form factors, the quark momentum…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , Ph. Hägler , R. Horsley , Y. Nakamura , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz , W. Schroers , H. Stüben , J. M. Zanotti

We report our numerical lattice QCD calculations of the isovector nucleon form factors for the vector and axialvector currents: the vector, induced tensor, axialvector, and induced pseudoscalar form factors. The calculation is carried out…

High Energy Physics - Lattice · Physics 2010-04-28 Takeshi Yamazaki , Yasumichi Aoki , Tom Blum , Huey-Wen Lin , Shigemi Ohta , Shoichi Sasaki , Robert Tweedie , James Zanotti

We report a new determination of the strange quark contribution to the proton's magnetic form factor at a four-momentum transfer Q2 = 0.1 (GeV/c)^2 from parity-violating e-p elastic scattering. The result uses a revised analysis of data…

Nuclear Experiment · Physics 2009-07-09 SAMPLE collaboration , D. T. Spayde

In this work, I report the latest lattice QCD calculations of nucleon and hyperon structure from chiral fermions in 2+1-flavor dynamical simulations. All calculations are done with a chirally symmetric fermion action, domain-wall fermions,…

High Energy Physics - Lattice · Physics 2007-07-27 Huey-Wen Lin

We present a numerical lattice quantum chromodynamics calculation of isovector form factors and the first few moments of the isovector structure functions of the nucleon. The calculation employs two degenerate dynamical flavors of…

High Energy Physics - Lattice · Physics 2008-12-18 Huey-Wen Lin , Tom Blum , Shigemi Ohta , Shoichi Sasaki , Takeshi Yamazaki

Nucleon isovector form factors calculated on a 2+1-flavor domain-wall-fermions ensemble with strange and degenerate up and down quarks at physical mass and lattice cut off, $a^{-1}$, of about 1.730(4) GeV, are reported. The ensemble was…

High Energy Physics - Lattice · Physics 2022-11-30 Shigemi Ohta

The possible existence of strange stars in the universe will help in the understanding of various properties of quantum chromodynamics, like asymptotic freedom and chiral symmetry restoration, which is otherwise very difficult to prove in…

Astrophysics · Physics 2007-05-23 Manjari Bagchi , Subharthi Ray , Mira Dey , Jishnu Dey

We present results on the nucleon electromagnetic form factors from Lattice QCD at momentum transfer up to about $12$~GeV$^2$. We analyze two gauge ensembles with the Wilson-clover fermion action, a lattice spacing of $a\approx 0.09$~fm and…

High Energy Physics - Lattice · Physics 2018-10-11 Christos Kallidonis , Sergey Syritsyn , Michael Engelhardt , Jeremy Green , Stefan Meinel , John Negele , Andrew Pochinsky

The flavor content of nucleon form factors is analyzed using two different theoretical approaches. The first is based on a phenomenological two-component model in which the external photon couples to both an intrinsic three-quark structure…

Nuclear Theory · Physics 2008-09-25 R. Bijker , E. Santopinto

Recent developments in lattice QCD calculation of flavor singlet nucleon matrix elements are reviewed. Substantial sea quark contributions are found in the $\pi$-$N\ \sigma$ term and the quark spin content of the nucleon such that the total…

High Energy Physics - Lattice · Physics 2009-10-28 Masanori Okawa

The nature of QCD phase transition is studied with massless up and down quarks and a light strange quark, using the Wilson formalism for quarks on a lattice with the temporal direction extension $N_t=4$. We find that the phase transition is…

High Energy Physics - Lattice · Physics 2009-10-28 Y. Iwasaki , K. Kanaya , S. Kaya , S. Sakai , T. Yoshié

Sea quark contributions to the scalar density and the axial current matrix elements of the nucleon are studied in lattice qcd with two flavours of dynamical wilson fermions. the results are compared to trends in heavy quark mass expansions,…

High Energy Physics - Lattice · Physics 2010-11-01 Apoorva Patel

We present a quenched lattice calculation of the weak nucleon form factors: vector (F_V(q^2)), induced tensor (F_T(q^2)), axial-vector (F_A(q^2)) and induced pseudo-scalar (F_P(q^2)) form factors. Our simulations are performed on three…

High Energy Physics - Lattice · Physics 2009-04-10 Shoichi Sasaki , Takeshi Yamazaki