Measurement of the B→Xsℓ+ℓ− Branching Fraction and Search for Direct CP Violation from a Sum of Exclusive Final States

We measure the total branching fraction of the flavor-changing neutral-current process B → X s ℓ + ℓ − , along with partial branching fractions in bins of dilepton and hadronic system ( X s ) mass, using a sample of 471 × 1 0 6 Υ ( 4 S ) → B ¯ B events recorded with the BABAR detector. The admixture...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Physical review letters 2014-05, Vol.112
Hauptverfasser: Lees, J. P., Poireau, V., Tisserand, V., Arnaud, N., Davier, M., Derkach, D., Grosdidier, G., Le Diberder, F., Lutz, A.M., Malaescu, B., Roudeau, P., Schune, M.H., Stocchi, A., Wormser, G., Bernard, D., Verderi, M., Emery, S., Hamel de Monchenault, G., Vasseur, G., Yèche, Ch, Akar, S., Ben-Haim, E., Bomben, M., Bonneaud, G.R., Briand, H., Calderini, G., Chauvau, J., Hamon, O., Leruste, Ph, Marchiori, G., Ocariz, J., Sitt, S.
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:We measure the total branching fraction of the flavor-changing neutral-current process B → X s ℓ + ℓ − , along with partial branching fractions in bins of dilepton and hadronic system ( X s ) mass, using a sample of 471 × 1 0 6 Υ ( 4 S ) → B ¯ B events recorded with the BABAR detector. The admixture of charged and neutral B mesons produced at PEP-II2 are reconstructed by combining a dilepton pair with 10 different X s final states. Extrapolating from a sum over these exclusive modes, we measure a lepton-flavor-averaged inclusive branching fraction B ( B → X s ℓ + ℓ − ) = [ 6.7 3 + 0.70 − 0.64 ( stat ) + 0.34 − 0.25 ( exp syst ) ± 0.50 ( model syst ) ] × 1 0 − 6 for m 2 ℓ + ℓ − > 0.1     GeV 2 / c 4 . Restricting our analysis exclusively to final states from which a decaying B meson's flavor can be inferred, we additionally report measurements of the direct C P asymmetry A C P in bins of dilepton mass; over the full dilepton mass range, we find A C P = 0.04 ± 0.11 ± 0.01 for a lepton-flavor-averaged sample.
ISSN:0031-9007
1079-7114
DOI:10.1103/PhysRevLett.112.211802