This title appears in the Scientific Report :
2012
Please use the identifier:
http://dx.doi.org/10.1016/j.ppnp.2012.01.012 in citations.
A lattice study of the strangeness content of the nucleon
A lattice study of the strangeness content of the nucleon
We determine the quark contributions to the nucleon spin Delta s, Delta u and Ad as well as their contributions to the nucleon mass, the a-terms. This is done by computing both, the quark line connected and disconnected contributions to the respective matrix elements, using the non-perturbatively im...
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Personal Name(s): | Bali, G.S. |
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Collins, S. / Göckeler, M. / Horsley, R. / Nakamura, Y. / Nobile, A. / Pleiter, D. / Rakow, P.E.L. / Sternbeck, A. / Schäfer, A. / Schierholz, G. / Zanotti, J.M. | |
Contributing Institute: |
Jülich Supercomputing Center; JSC |
Published in: | Progress in particle and nuclear physics, 67 (2012) S. 467 - 472 |
Imprint: |
Oxford [u.a.]
Pergamon Press
2012
|
Physical Description: |
467 - 472 |
DOI: |
10.1016/j.ppnp.2012.01.012 |
Document Type: |
Journal Article |
Research Program: |
Precision lattice QCD calculations Strong Interaction Supercomputing Training Network Computational Science and Mathematical Methods Scientific Computing |
Series Title: |
Progress in Particle and Nuclear Physics
67 |
Subject (ZB): | |
Publikationsportal JuSER |
We determine the quark contributions to the nucleon spin Delta s, Delta u and Ad as well as their contributions to the nucleon mass, the a-terms. This is done by computing both, the quark line connected and disconnected contributions to the respective matrix elements, using the non-perturbatively improved Sheikholeslami-Wohlert Wilson Fermionic action. We simulate n(F) = 2 mass degenerate sea quarks with a pion mass of about 285 MeV and a lattice spacing a approximate to 0.073 fm. The renormalization of the matrix elements involves mixing between contributions from different quark flavours. The pion-nucleon a-term is extrapolated to physical quark masses exploiting the sea quark mass dependence of the nucleon mass. We obtain the renormalized value sigma(pi N) = (38 +/- 12) MeV at the physical point and the strangeness fraction f(Ts) = sigma s/m(N) = 0.012(14)(-3)(+10) at our larger than physical sea quark mass. For the strangeness contribution to the nucleon spin we obtain Delta s ((MS)) over bar(root 7.4 GeV) = -0.020(10)(1). (C) 2012 Published by Elsevier B.V. |