Showing papers by "Junichi Tanaka published in 2001"
TL;DR: In this paper, the branching fraction of the inclusive radiative B meson decay B→Xsγ was measured to be 3.36±0.53(stat)± 0.42(sys)+0.50−0.54(th))×10−4.
199 citations
TL;DR: In this paper, the authors report measurements of the branching fractions for $B^0\to\pi+\pi-$, $K^+K^-$, K^+k^-$ and K^ 0\pi^0.
Abstract: We report measurements of the branching fractions for $B^0\to\pi^+\pi^-$, $K^+\pi^-$, $K^+K^-$ and $K^0\pi^0$, and $B^+\to\pi^+\pi^0$, $K^+\pi^0$, $K^0\pi^+$ and $K^+\overline{K}{}^0$. The results are based on 10.4 fb$^{-1}$ of data collected on the $\Upsilon$(4S) resonance at the KEKB $e^+e^-$ storage ring with the Belle detector, equipped with a high momentum particle identification system for clear separation of charged $\pi$ and $K$ mesons. We find ${\cal B}(B^0\to\pi^+\pi^-) =(0.56^{+0.23}_{-0.20}\pm 0.04)\times 10^{-5}$, ${\cal B}(B^0\to K^+\pi^-) =(1.93^{+0.34 +0.15}_{-0.32 -0.06})\times 10^{-5}$, ${\cal B}(B^+\to K^+\pi^0) =(1.63^{+0.35 +0.16}_{-0.33 -0.18})\times 10^{-5}$, ${\cal B}(B^+\to K^0\pi^+) =(1.37^{+0.57 +0.19}_{-0.48 -0.18})\times 10^{-5}$, and ${\cal B}(B^0\to K^0\pi^0) =(1.60^{+0.72 +0.25}_{-0.59 -0.27})\times 10^{-5}$, where the first and second errors are statistical and systematic. We also set upper limits of ${\cal B}(B^+\to\pi^+\pi^0)<1.34\times 10^{-5}$, ${\cal B}(B^0\to K^+K^-)<0.27\times 10^{-5}$, and ${\cal B}(B^+\to K^+\overline{K}{}^0)<0.50\times 10^{-5}$ at the 90% confidence level.
58 citations
TL;DR: In this article, measurements for two-body charmless hadronic B decays with an η′ meson in the final state using 111×106 B pairs collected with the Belle detector.
54 citations
TL;DR: The first observations of the B-->D+K-, D(*0)K-, and D(*+)K- decay processes are reported, using a data sample accumulated at the Upsilon(4S) resonance with the Belle detector at the KEKB e(+)e(-) storage ring.
Abstract: We report observations of the Cabibbo suppressed decays B{yields}D{sup (*)}K{sup -} using a 10.4 fb{sup -1} data sample accumulated at the {Upsilon}(4S) resonance with the Belle detector at the KEKB e{sup +}e{sup -} storage ring. We find that the ratios of Cabibbo suppressed to Cabibbo favored branching fractions are B(B{sup -}{yields}D{sup 0}K{sup -})/B(B{sup -} {yields}D{sup 0}{pi}{sup -})= 0.079{+-} 0.009{+-} 0.006 , B({bar B}{sup 0} {yields}D{sup +}K{sup -})/B({bar B}{sup 0 }{yields} D{sup +}{pi}{sup -}) =0.068 {+-}0.015 {+-}0.007 , B(B{sup -}{yields} D{sup *0}K{sup -}) /B(B{sup -} {yields}D{sup *0}{pi}{sup -})= 0.078{+-} 0.019{+-} 0.009 , and B({bar B}{sup 0}{yields} D{sup *+}K{sup -})/ B({bar B}{sup 0}{yields} D{sup *+}{pi}{sup -})=0.074{+-}0.015{+-} 0.006 . These are the first observations of the B{yields}D{sup +}K{sup -} , D{sup *0}K{sup -} , and D{sup *+}K{sup -} decay processes.
18 citations