Study of ¯ B 0 → D + h − ( h = K / π ) decays at Belle

Abstract

We present a measurement of the branching fractions of the Cabibbo favored ¯ B 0 → D + π − and the Cabibbo suppressed ¯ B 0 → D + K − decays. We find B ( ¯ B 0 → D + π − ) = ( 2.48 ± 0.01 ± 0.09 ± 0.04 ) × 10 − 3 and B ( ¯ B 0 → D + K − ) = ( 2.03 ± 0.05 ± 0.07 ± 0.03 ) × 10 − 4 decays, where the first uncertainty is statistical, the second is systematic, and the third uncertainty is due to the D + → K − π + π + branching fraction. The ratio of branching fractions of ¯ B 0 → D + K − and ¯ B 0 → D + π − is measured to be R D = [ 8.19 ± 0.20 ( stat ) ± 0.23 ( syst ) ] × 10 − 2 . These measurements are performed using the full Belle dataset, which corresponds to 772 × 10 6 B ¯ B pairs and use the Belle II software framework for data analysis