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ID 14499
本文ファイル
e114505.pdf 327 KB
著者
Aoki, S
Fukugita, M
Hashimoto, S
Ishizuka, N
Iwasaki, Y
Kanaya, K
Kaneko, T
Kuramashi, Y
Onogi, T
Tominaga, S
Tsutsui, N
Ukawa, A
Yamada, A
Yoshié, T
NDC
物理学
抄録(英)
We present a lattice QCD calculation of B→πlν semileptonic decay form factors in the small pion recoil momentum region. The calculation is performed on a quenched 163×48 lattice at β=5.9 with the nonrelativistic QCD action including the full 1/M terms. The form factors f1(v⋅kπ) and f2(v⋅kπ) defined in the heavy quark effective theory for which the heavy quark scaling is manifest are adopted, and we find that the 1/M correction to the scaling is small for the B meson. The dependence of the form factors on the light quark mass and on the recoil energy is found to be mild, and we use a global fit of the form factors at various quark masses and recoil energies to obtain model independent results for the physical differential decay rate. We find that the B* pole contribution dominates the form factor f+(q2) for small pion recoil energy, and obtain the differential decay rate integrated over the kinematic region q2>18 GeV2 to be |Vub|2×(1.18±0.37±0.08±0.31) psec-1, where the first error is statistical, the second is that from perturbative calculation, and the third is the systematic error from the finite lattice spacing and the chiral extrapolation. We also discuss the systematic errors in the soft pion limit for f0(qmax2) in the present simulation.
掲載誌名
Physical Review D
64巻
開始ページ
114505
出版年月日
2001
出版者
The American Physical Society
ISSN
1550-7998
出版者DOI
言語
英語
NII資源タイプ
学術雑誌論文
広大資料タイプ
学術雑誌論文
DCMIタイプ
text
フォーマット
application/pdf
著者版フラグ
publisher
権利情報
Copyright (c) 2001 The American Physical Society
関連情報URL
部局名
理学研究科