Measurement of the D<sup>∗−</sup> polarization in the decay B<sup>0</sup> → D<sup>∗−</sup>τ<sup>+</sup>ν<inf>τ</inf>

Date Issued
01-01-2018
Author(s)
Abdesselam, A.
Adachi, I.
Adamczyk, K.
Ahn, J. K.
Aihara, H.
Al Said, S.
Arinstein, K.
Arita, Y.
Asner, D. M.
Atmacan, H.
Aulchenko, V.
Aushev, T.
Ayad, R.
Aziz, T.
Babu, V.
Badhrees, I.
Bahinipati, S.
Bakich, A. M.
Ban, Y.
Bansal, V.
Barberio, E.
Barrett, M.
Bartel, W.
Behera, P.
Beleño, C.
Belous, K.
Berger, M.
Bernlochner, F.
Besson, D.
Bhardwaj, V.
Bhuyan, B.
Bilka, T.
Biswal, J.
Bloomfield, T.
Bobrov, A.
Bondar, A.
Bonvicini, G.
Bozek, A.
BraÄ ko, M.
Braun, N.
Breibeck, F.
Browder, T. E.
Campajola, M.
Cao, L.
Caria, G.
ÄŒervenkov, D.
Chang, M. C.
Chang, P.
Chao, Y.
Cheaib, R.
Chekelian, V.
Chen, A.
Chen, K. F.
Cheon, B. G.
Chilikin, K.
Chistov, R.
Cho, H. E.
Cho, K.
Chobanova, V.
Choi, S. K.
Choi, Y.
Choudhury, S.
Cinabro, D.
Crnkovic, J.
Cunliffe, S.
Czank, T.
Danilov, M.
Dash, N.
Di Carlo, S.
Dingfelder, J.
Doležal, Z.
Dong, T. V.
Dossett, D.
Drásal, Z.
Drutskoy, A.
Dubey, S.
Dutta, D.
Eidelman, S.
Epifanov, D.
Fast, J. E.
Feindt, M.
Ferber, T.
Frey, A.
Frost, O.
Fulsom, B. G.
Garg, R.
Gaur, V.
Gabyshev, N.
Garmash, A.
Gelb, M.
Gemmler, J.
Getzkow, D.
Giordano, F.
Giri, A.
Goldenzweig, P.
Golob, B.
Greenwald, D.
Perdekamp, M. Grosse
Grygier, J.
Grzymkowska, O.
Abstract
We report the first measurement of the D∗− meson polarization in the decay B0 → D∗−τ+ντ using the full data sample of 772×106 BB¯ pairs recorded with the Belle detector at the KEKB electron-positron collider. Our result, FLD∗ = 0.60 ±0.08(stat) ±0.04(sys), where FLD∗ denotes the D∗− meson longitudinal polarization fraction, agrees within about 1.7 standard deviations of the standard model prediction.