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Related papers: Hunting for the strangeness content of the nucleon

200 papers

We present results on the scalar strangeness and charm contents of the nucleon and of the disconnected contributions to the nucleon spin. These are obtained on two flavour non-perturbatively improved Sheikholeslami-Wilson configurations at…

High Energy Physics - Lattice · Physics 2010-11-05 Gunnar Bali , Sara Collins , Andreas Schaefer

Many Lattice QCD observables of phenomenological interest include so-called all-to-all propagators. The computation of these requires prohibitively large computational resources, unless they are estimated stochastically. This is usually…

High Energy Physics - Lattice · Physics 2011-03-28 Gunnar S. Bali , Sara Collins , Andreas Schaefer

We compute the strangeness and light-quark contributions Delta s, Delta u and Delta d to the proton spin in nf=2 lattice QCD at a pion mass of about 285 MeV and at a lattice spacing a approx 0.073 fm, using the non-perturbatively improved…

There are several different experimental indications, such as the strangeness contribution to the magnetic moment of the proton, sigma_{\pi N} term, strange spin polarization, ratio of strange and non strange quark flavor distributions…

High Energy Physics - Phenomenology · Physics 2008-11-26 Harleen Dahiya , Manmohan Gupta

The extraction of the nucleon's strangeness axial charge, Delta_s, from inclusive, quasielastic neutral current neutrino cross sections is studied within the framework of the plane-wave impulse approximation. We find that the value of…

Nuclear Theory · Physics 2008-11-26 M. B. Barbaro , A. De Pace , T. W. Donnelly , A. Molinari , M. J. Musolf

The implications of the empirical signatures for the positivity of the strangeness magnetic moment $\mu_s$, and the negativity of the strangeness contribution to the proton spin $\Delta_s$, on the possible $uuds\bar s$ configurations of…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. S. An , B. S. Zou , D. O. Riska

We determine the quark contributions to the nucleon spin Delta s, Delta u and Delta d as well as their contributions to the nucleon mass, the sigma-terms. This is done by computing both, the quark line connected and disconnected…

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…

High Energy Physics - Phenomenology · Physics 2007-10-19 Harleen Dahiya , Manmohan Gupta

The strange quark content of the nucleon, as well as other matrix elements, can be calculated on the lattice by examining correlations between the nucleon propagator and the quark condensate. The largest contribution to statistical error…

High Energy Physics - Lattice · Physics 2011-07-22 Walter Freeman , Doug Toussaint

Contributions of strange quarks to the mass and spin of the nucleon, characterized by the observables f_Ts and Delta s, respectively, are investigated within lattice QCD. The calculation employs a 2+1-flavor mixed-action lattice scheme,…

High Energy Physics - Lattice · Physics 2013-05-30 M. Engelhardt

The strangeness contribution to the electric and magnetic properties of the nucleon has been under investigation experimentally for many years. Lattice Quantum Chromodynamics (LQCD) gives theoretical predictions of these measurements by…

High Energy Physics - Lattice · Physics 2008-01-24 Dean Darnell

We present preliminary results for strangeness form factors of the nucleon computed on the CLS ensembles with $N_f=2+1$ flavors of O($a$)-improved Wilson fermions. Our calculations are performed at two values of the lattice spacing ($a \in…

High Energy Physics - Lattice · Physics 2018-10-26 Dalibor Djukanovic , Harvey Meyer , Konstantin Ottnad , Georg von Hippel , Jonas Wilhelm , Hartmut Wittig

Determining the nonperturbative $s\bar{s}$ content of the nucleon has attracted considerable interest and been the subject of numerous experimental searches. These measurements used a variety of reactions and place important limits on the…

Nuclear Theory · Physics 2015-06-02 T. J. Hobbs , Mary Alberg , Gerald A. Miller

Strange matrix elements of the nucleon are calculated within the light-cone formulation of the meson cloud model. The $Q^2$ dependence of the strange vector and axial vector form factors is computed, and the strangeness radius and magnetic…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. Melnitchouk , M. Malheiro

We present a non-perturbative calculation of the strangeness of the nucleon $y_N$ within the framework of lattice QCD. This observable is known to be an important cornerstone to interpret results from direct dark matter detection…

We have calculated the strangeness contribution to the magnetic moments of the nucleon and $\Delta$ decuplet baryons in the chiral constituent quark model with configuration mixing ($\chi$CQM$_{{\rm config}}$) which is known to provide a…

High Energy Physics - Phenomenology · Physics 2012-01-23 Harleen Dahiya , Neetika Sharma

We review the state of our knowledge concerning the contribution of strange quarks to various nucleon properties. In the case of the electric and magnetic form factors, the level of agreement between theory and experiment is very…

Nuclear Theory · Physics 2022-03-02 A. W. Thomas , P. E. Shanahan , R. D. Young

The strangeness contribution to the nucleon magnetic moment is calculated at the one-loop level in a relativistic SU(3) chiral potential model and is found to be {\em positive}, that is, with an {\em opposite} sign to the nucleon…

High Energy Physics - Phenomenology · Physics 2007-05-23 X. B. Chen , X. S. Chen , Amand Faessler , Th. Gutsche , F. Wang

Quark line disconnected matrix elements of an operator, such as the axial current, are difficult to compute on the lattice. The standard method uses a stochastic estimator of the operator, which is generally very noisy. We discuss and…

High Energy Physics - Lattice · Physics 2019-01-16 R. Horsley , Y. Nakamura , H. Perlt , D. Pleiter , P. E. L. Rakow , G. Schierholz , A. Schiller , H. Stüben , R. D. Young , J. M. Zanotti

We review a recent theoretical determination of the strange quark content of the electromagnetic form factors of the nucleon. These are compared with a global analysis of current experimental measurements in parity-violating electron…

Nuclear Theory · Physics 2008-11-26 Ross D. Young
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