Measurement of the charge asymmetry in semileptonic Bs0 decays

• Published in: Physical review letters 2007-04, Vol.98 (15), p.151801-151801
• Main Authors: Abazov, V M, Abbott, B, Abolins, M, Acharya, B S, Adams, M, Adams, T, Aguilo, E, Ahn, S H, Ahsan, M, Alexeev, G D, Alkhazov, G, Alton, A, Alverson, G, Alves, G A, Anastasoaie, M, Ancu, L S, Andeen, T, Anderson, S, Andrieu, B, Anzelc, M S, Arnoud, Y, Arov, M, Askew, A, Asman, B, Assis Jesus, A C S, Atramentov, O, Autermann, C, Avila, C, Ay, C, Badaud, F, Baden, A, Bagby, L, Baldin, B, Bandurin, D V, Banerjee, P, Banerjee, S, Barberis, E, Bargassa, P, Baringer, P, Barnes, C, Barreto, J, Bartlett, J F, Bassler, U, Bauer, D, Beale, S, Bean, A, Begalli, M, Begel, M, Belanger-Champagne, C, Bellantoni, L, Bellavance, A, Benitez, J A, Beri, S B, Bernardi, G, Bernhard, R, Berntzon, L, Bertram, I, Besançon, M, Beuselinck, R, Bezzubov, V A, Bhat, P C, Bhatnagar, V, Binder, M, Biscarat, C, Blackler, I, Blazey, G, Blekman, F, Blessing, S, Bloch, D, Bloom, K, Boehnlein, A, Boline, D, Bolton, T A, Borissov, G, Bos, K, Bose, T, Brandt, A, Brock, R, Brooijmans, G, Bross, A, Brown, D, Buchanan, N J, Buchholz, D, Buehler, M, Buescher, V, Burdin, S, Burke, S, Burnett, T H, Busato, E, Buszello, C P, Butler, J M, Calfayan, P, Calvet, S, Cammin, J, Caron, S, Carvalho, W, Casey, B C K, Cason, N M, Castilla-Valdez, H, Chakrabarti, S
• Format: Article
• Language: English
• ISSN: 0031-9007
• DOI: 10.1103/PhysRevLett.98.151801

We have performed the first direct measurement of the time-integrated flavor untagged charge asymmetry in semileptonic Bs0 decays ASLs,unt by comparing the decay rate of Bs0-->micro+Ds-nuX, where Ds- -->phipi- and phi-->K+K-, with the charge-conjugate Bs0 decay rate. This sample was selected from 1.3 fb-1 of data collected by the D0 experiment in run II of the Fermilab Tevatron collider. We obtain ASLs,unt=[1.23+/-0.97(stat)+/-0.17(syst)]x10(-2). Assuming that Deltam(s)/Gamma(s)>>1, this result can be translated into a measurement of the CP-violating phase in Bs0 mixing: DeltaGamma(s)/Deltam(s)tanphi(s)=[2.45+/-1.93(stat)+/-0.35(syst)]x10(-2).