Quenched spectroscopy with fixed-point and chirally improved fermions

BGR Collaboration; Christof Gattringer; Meinulf Gockeler; Peter Hasenfratz; Simon Hauswirth; Kieran Holland; Thomas Jorg; Keisuke J. Juge; C. B. Lang; Ferenc Niedermayer; P. E. L. Rakow; Stefan Schaefer; Andreas Schafer

doi:10.1016/j.nuclphysb.2003.10.044

arXiv · hep-lat/0307013

Quenched spectroscopy with fixed-point and chirally improved fermions

BGR Collaboration·Christof Gattringer·Meinulf Gockeler·Peter Hasenfratz·Simon Hauswirth·Kieran Holland·Thomas Jorg·Keisuke J. Juge·C. B. Lang·Ferenc Niedermayer·P. E. L. Rakow·Stefan Schaefer·Andreas Schafer

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Abstract

We present results from quenched spectroscopy calculations with the parametrized fixed-point and the chirally improved Dirac operators. Both these operators are approximate solutions of the Ginsparg-Wilson equation and have good chiral properties. This allows us to work at small quark masses and we explore pseudoscalar-mass to vector-mass ratios down to 0.28. We discuss meson and baryon masses, their scaling properties, finite volume effects and compare our results with recent large scale simulations. We find that the size of quenching artifacts of the masses is strongly correlated with their experimentally observed widths and that the gauge and hadronic scales are consistent.

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BGR Collaboration, Christof Gattringer, Meinulf Gockeler, Peter Hasenfratz, Simon Hauswirth, Kieran Holland, Thomas Jorg, Keisuke J. Juge, C. B. Lang, Ferenc Niedermayer, P. E. L. Rakow, Stefan Schaefer, Andreas Schafer. 2003-11-21. Quenched spectroscopy with fixed-point and chirally improved fermions. https://doi.org/10.1016/j.nuclphysb.2003.10.044

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