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arXiv · hep-lat/0510071

Heavy-light mesons with domain wall fermions

Abstract

We present RBC heavy-light meson spectroscopy with quenched DBW2 gauge configurations at lattice cutoff of about 3 GeV. Both heavy and light quarks are described by domain-wall fermions (DWF). The heavy quark mass ranges between 0.1 and 0.4 lattice units, covering charm. The light quark mass ranges between 0.008 and 0.04, covering strange. In particular, we discuss charmed (D and D*) and charm-strange (Ds and DsJ) mesons with spin-parity JP= 0+/- and 1+/-. The preliminary results indicate that DWF describe charm on the quenched DBW2 ensemble at this cutoff. The masses of the JP=0+/- and 1+/- D, D*, Ds and DsJ meson states are well reproduced to within a few %; their parity splitting, DeltaJ, are better reproduced than previous works, with only 10-20 % over estimations; the experimental observation that the splitting for non-strange states is bigger than that for strange states is reproduced as well; but the hyperfine splittings are only 60-65 % reproduced. Regarding the depenence on heavy quark mass, J=0 and J=1 parity splittings are degenerate for heavy quark mass heavier than 0.2-0.3 lattice units a; the J=0 parity splitting increases as the heavy quark mass decreases further while the J=1 splitting does not.

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BibTeXRIS

HueyWen Lin, Shigemi Ohta, Norikazu Yamada. 2005-10-12. Heavy-light mesons with domain wall fermions. https://arxiv.org/abs/hep-lat/0510071

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