@article{oai:niigata-u.repo.nii.ac.jp:00002365,
 author = {Khan, A.Ali and Aoki, S. and Burkhalter, R. and Ejiri, S. and Fukugita, M. and Hashimoto, S. and Ishizuka, N. and Iwasaki, Y. and Kanaya, K. and Kaneko, T. and Kuramashi, Y. and Manke, T. and Nagai, K.I. and Okawa, M. and Shanahan, H.P. and Ukawa, A. and Yoshie, T. and CP-PACS, Collaboration},
 issue = {3},
 journal = {Physical Review D, Physical Review D},
 month = {Jul},
 note = {We present a calculation of the B and D meson decay constants in lattice QCD with two (N f =2) flavors of light dynamical quarks, using an O(a)-improved Wilson action for both light and heavy quarks and a renormalization-group improved gauge action. Simulations are made at three values of lattice spacing a=0.22,0.16,0.11 fm and four values of sea quark mass in the range m PS /m V ≈0.8-0.6. Our provisional estimate for the continuum values of the decay constants are f Bd =208(10)(29) MeV, f Bs =250(10)(35)( +8 -0 ) MeV, f Dd =225(14)(40) MeV, f Ds =267(13)(48)( +10 -0 ) MeV for N f =2 where the statistical and systematic errors are separately listed, and the third error for f Bs and f Ds shows the uncertainty of the determination of the strange quark mass. We also carry out a set of quenched simulations using the same action to make a direct examination of sea quark effects. Taking the ratio of results for N f =2 and N f =0, we obtain f N f =2 Bd /f N f =0 Bd =1.11(6),f N f =2 Bs /f N f =0 Bs =1.14(5),f N f =2 Dd /f N f =0 Dd =1.03(6),f N f =2 Ds /f N f =0 Ds =1.07(5). They show a 10–15 % increase in the N f =2 results over those of N f =0 for the B meson decay constants, while evidence for such a trend is statistically less clear for the D meson decay constants.},
 title = {Decay constants of B and D mesons from improved relativistic lattice QCD with two flavours of sea quarks},
 volume = {64},
 year = {2001}
}