Measurement of the Cabibbo-Kobayashi-Maskawa Angle γ in B∓→D(*)K∓ Decays with a Dalitz Analysis of D→K0Sπ−π+

Abstract

We report on a measurement of the Cabibbo-Kobayashi-Maskawa C P -violating phase γ through a Dalitz analysis of neutral D decays to K 0 S π − π + in the processes B ∓ → D ( * ) K ∓ , D ∗ → D π 0 , D γ . Using a sample of 227 × 10 6 B ¯¯¯ B pairs collected by the BABAR detector, we measure the amplitude ratios r B = 0.12 ± 0.08 ± 0.03 ± 0.04 and r ∗ B = 0.17 ± 0.10 ± 0.03 ± 0.03 , the relative strong phases δ B = ( 104 ± 45 + 17 + 16 − 21 − 24 ) ° and δ ∗ B = ( − 64 ± 41 + 14 − 12 ± 15 ) ° between the amplitudes A ( B − → ¯¯¯ D ( * ) 0 K − ) and A ( B − → D ( * ) 0 K − ) , and γ = ( 70 ± 31 + 12 + 14 − 10 − 11 ) ° . The first error is statistical, the second is the experimental systematic uncertainty, and the third reflects the Dalitz model uncertainty. The results for the strong and weak phases have a twofold ambiguity.