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Related papers: Strangeness in the Nucleon

200 papers

The strange quark contributions to the electromagnetic form factors of the proton are ideal quantities to study the role of hidden flavor in the properties of the proton. This has motivated intense experimental measurements of these form…

Nuclear Theory · Physics 2020-08-05 Ali Alkathiri , Ross D. Young , James M. Zanotti

By imposing the constraints of charge symmetry we show that the strangeness magnetic moment of the nucleon can be expressed in terms of empirical magnetic moments and ratios of valence quark magnetic moments. The latter are determined using…

High Energy Physics - Lattice · Physics 2009-11-10 D. B. Leinweber , S. Boinepalli , A. W. Thomas , A. G. Williams , R. D. Young , J. M. Zanotti , J. B. Zhang

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…

We investigate the transverse quark spin densities of the nucleon with the lowest moment within the framework of the SU(3) chiral quark-soliton model, emphasizing the strange quark spin density. Based on previous results of the vector and…

High Energy Physics - Phenomenology · Physics 2015-05-28 Tim Ledwig , Hyun-Chul Kim

We have revisited the calculation of the neutron electric dipole moment in the presence of the CP-violating operators up to dimension five based on the chiral perturbation theory. Especially, we focus on the contribution of strangeness…

High Energy Physics - Phenomenology · Physics 2013-04-02 Kaori Fuyuto , Junji Hisano , Natsumi Nagata

We investigate the strange electric and magnetic form factors of the nucleon in the framework of heavy baryon chiral perturbation theory to third order in the chiral expansion. All counterterms can be fixed from data. In particular, the two…

Nuclear Theory · Physics 2009-10-31 Thomas R. Hemmert , Bastian Kubis , Ulf-G. Meißner

The role of the strange quarks on the low-energy interactions of the proton can be probed through the strange electromagnetic form factors. Knowledge of these form factors provides essential input for parity-violating processes and…

High Energy Physics - Lattice · Physics 2020-02-19 C. Alexandrou , S. Bacchio , M. Constantinou , J. Finkenrath , K. Hadjiyiannakou , K. Jansen , G. Koutsou

The strange quark contribution to the vector and axial form factors of the nucleon has been determined for momentum transfers in the range $0.45<Q^2<1.0$ GeV$^2$. The results are obtained via a combined analysis of forward-scattering,…

High Energy Physics - Experiment · Physics 2008-11-26 S. F. Pate , D. W. McKee , V. Papavassiliou

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

The status of theoretical calculations of the strange quark vector current form factors of the nucleon is reviewed.

High Energy Physics - Phenomenology · Physics 2009-10-30 M. J. Ramsey-Musolf

We report a lattice QCD calculation of the strange quark contribution to the nucleon's magnetic moment and charge radius. This analysis presents the first direct determination of strange electromagnetic form factors including at the…

High Energy Physics - Phenomenology · Physics 2017-01-30 Raza Sabbir Sufian , Yi-Bo Yang , Andrei Alexandru , Terrence Draper , Keh-Fei Liu , Jian Liang

The strange-quark vector current form factors of the nucleon are analyzed within the framework of dispersion relations. Particular attention is paid to contributions made by $K\bar{K}$ intermediate states to the form factor spectral…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. J. Musolf , H. -W. Hammer , D. Drechsel

Certain dark matter interactions with nuclei are mediated possibly by a scalar or pseudoscalar Higgs boson. The estimation of the corresponding cross sections requires a correct evaluation of the couplings between the scalar or pseudoscalar…

High Energy Physics - Phenomenology · Physics 2015-06-04 Hai-Yang Cheng , Cheng-Wei Chiang

We present an improved determination of the strange quark and anti-quark parton distribution functions of the proton by means of a global QCD analysis that takes into account a comprehensive set of strangeness-sensitive measurements:…

High Energy Physics - Phenomenology · Physics 2021-05-04 Ferran Faura , Shayan Iranipour , Emanuele R. Nocera , Juan Rojo , Maria Ubiali

The behavior of the $\phi$ meson at finite density is studied, making use of a QCD sum rule approach in combination with the maximum entropy method. It is demonstrated that a possible mass shift of the $\phi$ in nuclear matter is strongly…

High Energy Physics - Phenomenology · Physics 2015-02-10 Philipp Gubler , Keisuke Ohtani

The enhancement of strange particle production observed in nucleus-nucleus collisions at CERN is explained by the combined effect of the increase in the relative number of strings containing strange constitutents at the ends, and the final…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. Capella

The strangeness contribution to the vector and axial form factors of the nucleon is presented for momentum transfers in the range $0.45<Q^2<1.0$ GeV$^2$. The results are obtained via a combined analysis of forward-scattering…

High Energy Physics - Experiment · Physics 2009-11-11 S. F. Pate , G. A. MacLachlan , D. W. McKee , V. Papavassiliou

The outcome of the SAMPLE Experiment suggests that the strange-quark contribution to the nucleon magnetic moment, G_M^s(0), may be greater than zero. This result is very difficult to reconcile with expectations based on the successful…

High Energy Physics - Lattice · Physics 2010-02-17 Derek B. Leinweber , Anthony W. Thomas

We discuss two descriptions of the nucleon's strange vector form factors in the framework of vector meson dominance. The first, an updated and extended version of Jaffe's dispersion analysis, approximates the spectral functions of the form…

High Energy Physics - Phenomenology · Physics 2009-10-28 Hilmar Forkel

Relativistic corrections to the strange axial form factor are evaluated within a light-cone formalism, taking into account effects due to the breaking of Lorentz covariance associated with the use of one-body currents. Similar corrections…

High Energy Physics - Phenomenology · Physics 2009-10-31 W. Melnitchouk , M. Malheiro