dc.contributor |
Universitat de Barcelona |
dc.contributor.author |
Garra Ticó, Jordi |
dc.contributor.author |
Graugés Pous, Eugeni |
dc.contributor.author |
BABAR Collaboration |
dc.date |
2019-04-08T09:55:03Z |
dc.date |
2019-04-08T09:55:03Z |
dc.date |
2010-10-11 |
dc.date |
2019-04-08T09:55:03Z |
dc.identifier.citation |
1550-7998 |
dc.identifier.citation |
601952 |
dc.identifier.uri |
http://hdl.handle.net/2445/131736 |
dc.format |
18 p. |
dc.format |
application/pdf |
dc.language.iso |
eng |
dc.publisher |
American Physical Society |
dc.relation |
Reproducció del document publicat a: https://doi.org/10.1103/PhysRevD.82.072006 |
dc.relation |
Physical Review D, 2010, vol. 82, num. 7, p. 072006 |
dc.relation |
https://doi.org/10.1103/PhysRevD.82.072006 |
dc.rights |
(c) American Physical Society, 2010 |
dc.rights |
info:eu-repo/semantics/openAccess |
dc.subject |
Física de partícules |
dc.subject |
Experiments |
dc.subject |
Particle physics |
dc.subject |
Experiments |
dc.title |
Search for b→u transitions in B−→DK− and D∗K− decays |
dc.type |
info:eu-repo/semantics/article |
dc.type |
info:eu-repo/semantics/publishedVersion |
dc.description.abstract |
We report results from an updated study of the suppressed decays B − → D K − and B − → D ∗ K − followed by D → K + π − , where D ( * ) indicates a D ( * ) 0 or a ¯¯¯ D ( * ) 0 meson, and D ∗ → D π 0 or D ∗ → D γ . These decays are sensitive to the Cabibbo-Kobayashi-Maskawa unitarity triangle angle γ due to interference between the b → c transition B − → D ( * ) 0 K − followed by the doubly Cabibbo-suppressed decay D 0 → K + π − , and the b → u transition B − → ¯¯¯ D ( * ) 0 K − followed by the Cabibbo-favored decay ¯¯¯ D 0 → K + π − . We also report an analysis of the decay B − → D ( * ) π − with the D decaying into the doubly Cabibbo-suppressed mode D → K + π − . Our results are based on 467 × 10 6 Υ ( 4 S ) → B ¯¯¯ B decays collected with the BABAR detector at SLAC. We measure the ratios R ( * ) of the suppressed ( [ K + π − ] D K − / π − ) to favored ( [ K − π + ] D K − / π − ) branching fractions as well as the C P asymmetries A ( * ) of those modes. We see indications of signals for the B − → D K − and B − → D ∗ D π 0 K − suppressed modes, with statistical significances of 2.1 and 2.2 σ , respectively, and we measure: R D K = ( 1.1 ± 0.6 ± 0.2 ) × 10 − 2 , A D K = − 0.86 ± 0.47 + 0.12 − 0.16 , R ∗ ( D π 0 ) K = ( 1.8 ± 0.9 ± 0.4 ) × 10 − 2 , A ∗ ( D π 0 ) K = + 0.77 ± 0.35 ± 0.12 , R ∗ ( D γ ) K = ( 1.3 ± 1.4 ± 0.8 ) × 10 − 2 , A ∗ ( D γ ) K = + 0.36 ± 0.94 + 0.25 − 0.41 , where the first uncertainty is statistical and the second is systematic. We use a frequentist approach to obtain the magnitude of the ratio r B ≡ | A ( B − → ¯¯¯ D 0 K − ) / A ( B − → D 0 K − ) | = ( 9.5 + 5.1 − 4.1 ) % , with r B < 16.7 % at 90% confidence level. In the case of B − → D ∗ K − we find r ∗ B ≡ | A ( B − → ¯¯¯ D * 0 K − ) / A ( B − → D * 0 K − ) | = ( 9.6 + 3.5 − 5.1 ) % , with r ∗ B < 15.0 % at 90% confidence level. |