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Measurement of the Branching Fraction for B^0 --> a1(1260)+-pi-+ with 535 Million BBbar Pairs

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 نشر من قبل Atsuko Kibayashi
 تاريخ النشر 2007
  مجال البحث
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We present a measurement of the branching fraction for the decay B^0->a1+(1260)pi- with a1+->pi+pi+pi- using a data sample containing 535x10^6 BBbar pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider operating at the Upsilon(4S) resonance. We measure the branching fraction Br(B^0->a1+pi-)Br(a1+->pi+pi+pi-) = (14.9 +- 1.6 +- 2.3)x10^-6, where the first and second errors are statistical and systematic, respectively.



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