name

Arifa Ali Khan

refid

4879

email

arifa@rccp.tsukuba.ac.jp

title

B Meson Decay Constants in Nf = 2 full QCD from CP-PACS - A parallel study with NRQCD and clover heavy quark actions -

collaboration

CP-PACS collaboration:
A.~Ali Khan, S.~Aoki, R.~Burkhalter, S.~Ejiri,
M.~Fukugita, S.~Hashimoto, N.~Ishizuka, Y.~Iwasaki,
K.~Kanaya, T.~Kaneko, Y.~Kuramashi, T.~Manke, K.~Nagai,
M.~Okamoto, M.~Okawa, H.P.~Shanahan, A.~Ukawa, T.~Yoshi\'e

abstract

We present final results from a systematic study of $f_B$, $f_{B_s}$ and
$f_{B_s}/f_B$ in two-flavor full QCD. Analyses are carried out on a set of
gauge configurations generated with a renormalization group-improved gauge
action and a tree-level tadpole-improved clover quark action at a range of
lattice spacings 1GeV$\leq 1/a \leq 2$GeV. For sea quarks we use four
values of quark masses in a range $0.5 m_s \leq m \leq 3 m_s$. For light
valence quarks we also employ a tree-level tadpole-improved clover action.
Heavy quarks are studied with a heavy quark clover action using the
Fermilab reinterpretation, and an NRQCD action corrected through $O(1/M)$,
at a range of masses around the actual $b$ quark mass. We report the
physical values of the decay constants and discuss scaling and systematic
errors. We examine sea quark effects in the decay constants using results
from a parallel set of quenched runs made with the same lattice actions at
similar lattice spacings as those of the dynamical runs.

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