$Measurement of the differential branching fraction and forward-backward asymmetry for B --> K()l+l$

Measurement of the differential branching fraction and forward-backward asymmetry for B --> K()l+l

We study B --> K(*)l+l- decays (l = e, mu) based on a data sample of 657 x 10(6) BB pairs collected with the Belle detector at the KEKB e+e- collider. We report the differential branching fraction, isospin asymmetry, K* polarization, and the forward-backward asymmetry (A(FB)) as functions of q2 =...

Ausführliche Beschreibung

Gespeichert in:

Bibliographische Detailangaben
Veröffentlicht in:	Physical review letters 2009-10, Vol.103 (17), p.171801-171801, Article 171801
Hauptverfasser:	Wei, J-T, Chang, P, Adachi, I, Aihara, H, Aulchenko, V, Aushev, T, Bakich, A M, Balagura, V, Barberio, E, Bondar, A, Bozek, A, Bracko, M, Browder, T E, Chang, Y-W, Chao, Y, Chen, A, Chen, K-F, Cheon, B G, Chiang, C-C, Cho, I-S, Choi, Y, Dalseno, J, Drutskoy, A, Dungel, W, Eidelman, S, Gabyshev, N, Goldenzweig, P, Golob, B, Ha, H, Han, B-Y, Hayasaka, K, Hayashii, H, Hazumi, M, Horii, Y, Hoshi, Y, Hou, W-S, Hyun, H J, Iijima, T, Inami, K, Itoh, R, Iwasaki, M, Iwasaki, Y, Kah, D H, Kaji, H, Kang, J H, Kapusta, P, Katayama, N, Kawasaki, T, Kichimi, H, Kim, H J, Kim, H O, Kim, S K, Kim, Y I, Kim, Y J, Kinoshita, K, Ko, B R, Korpar, S, Krizan, P, Krokovny, P, Kuzmin, A, Kwon, Y-J, Kyeong, S-H, Lange, J S, Lee, M J, Lee, S E, Lesiak, T, Li, J, Limosani, A, Liu, C, Liventsev, D, Louvot, R, Mandl, F, Matyja, A, McOnie, S, Medvedeva, T, Miyabayashi, K, Miyata, H, Miyazaki, Y, Mizuk, R, Nakano, E, Nakao, M, Nakazawa, H, Natkaniec, Z, Nishida, S, Nishimura, K, Nitoh, O, Nozaki, T, Ogawa, S, Ohshima, T, Okuno, S, Ozaki, H, Pakhlova, G, Park, C W, Park, H, Park, H K, Park, K S, Piilonen, L E, Rozanska, M, Sahoo, H, Sakai, K
Format:	Artikel
Sprache:	eng
Schlagworte:	ANTILEPTONS ANTIMATTER ANTIPARTICLES ASYMMETRY B MESONS BEAUTY MESONS BEAUTY PARTICLES BOSONS BRANCHING RATIO DECAY DIMENSIONLESS NUMBERS ELECTRONS ELEMENTARY PARTICLES FERMIONS FIELD THEORIES GRAND UNIFIED THEORY HADRONS INTERACTIONS ISOSPIN KAONS LEPTONS MATHEMATICAL MODELS MATTER MESONS MUONS PAIR PRODUCTION PARTICLE DECAY PARTICLE MODELS PARTICLE PRODUCTION PARTICLE PROPERTIES PHYSICS OF ELEMENTARY PARTICLES AND FIELDS POLARIZATION POSITRONS PSEUDOSCALAR MESONS QUANTUM FIELD THEORY STANDARD MODEL STRANGE MESONS STRANGE PARTICLES UNIFIED GAUGE MODELS
Online-Zugang:	Volltext
Tags:	Tag hinzufügen Keine Tags, Fügen Sie den ersten Tag hinzu!

Beschreibung
Zusammenfassung:	We study B --> K()l+l- decays (l = e, mu) based on a data sample of 657 x 10(6) BB pairs collected with the Belle detector at the KEKB e+e- collider. We report the differential branching fraction, isospin asymmetry, K polarization, and the forward-backward asymmetry (A(FB)) as functions of q2 = M(ll)(2)c2. The fitted A(FB) spectrum exceeds the standard model expectation by 2.7 standard deviations. The measured branching fractions are B(B --> Kl+l-) = (10.7(-1.0)(+1.1) +/- 0.9) x 10(-7) and B(B --> Kl+l-) = (4.8(-0.4)(+0.5) +/- 0.3) x 10(-7), where the first errors are statistical and the second are systematic, with the muon to electron ratios R(K) = 0.83 +/- 0.17 +/- 0.08 and R(K) = 1.03 +/- 0.19 +/- 0.06.
ISSN:	0031-9007 1079-7114
DOI:	10.1103/PhysRevLett.103.171801