Search for Exclusive B Decays to J and $\eta$ or $\pi^{0}$ with the L3 Detector

• Published in: Physics letters. B 1997-01, Vol.391, p.481-490
• Main Authors: Acciarri, M., Adriani, O., Aguilar-Benitez, M., Ahlen, S., Alpat, B., Alcaraz, J., Alemanni, G., Allaby, J., Aloisio, A., Alverson, G., Alviggi, M G., Ambrosi, G., Anderhub, H., Andreev, V P., Angelescu, T., Anselmo, F., Antreasyan, D., Arefiev, A., Azemoon, T., Aziz, T., Bagnaia, P., Baksay, L., Ball, R C., Banerjee, S., Banicz, K., Barillere, R., Barone, L., Bartalini, P., Baschirotto, A., Basile, M., Battiston, R., Bay, A., Becattini, F., Becker, U., Behner, F., Berdugo, J., Berges, P., Bertucci, B., Betev, B L., Bhattacharya, S., Biasini, M., Biland, A., Bilei, G M., Blaising, J J., Blyth, S C., Bobbink, G J., Bock, R., Bohm, A., Borgia, B., Boucham, A., Bourilkov, D., Bourquin, M., Boutigny, D., Branson, J G., Brigljevic, V., Brock, I C., Buffini, A., Buijs, A., Burger, J D., Burger, W J., Busenitz, J., Buytenhuijs, A., Cai, X D., Campanelli, M., Capell, M., Cara Romeo, G., Caria, M., Carlino, G., Cartacci, a M., Casaus, J., Castellini, G., Cavallari, F., Cavallo, N., Cecchi, C., Cerrada, M., Cesaroni, F., Chamizo, M., Chan, A., Chang, y H., Chaturvedi, U K., Chemarin, M., Chen, A., Chen, G., Chen, G M., Chen, H F., Chen, H S., Chen, M., Chiefari, G., Chien, C Y., Choi, M T., Cifarelli, L., Cindolo, F., Civinini, C., Clare, I., Clare, R., Cohn, H O., Coignet, G., Colijn, a P., Colino, N., Commichau, V.
• Format: Article
• Language: English
• Subjects: High Energy Physics - Experiment; Physics
• ISSN: 0370-2693
• DOI: 10.1016/S0370-2693(96)01584-5

A search for exclusive decays of $\ensuremath{\mathrm{B_d^0}}$ and $\ensuremath{\mathrm{B_s^0}}$ mesons has been performed in the channels $\ensuremath{\mathrm{B_d^0}\rightarrow\mathrm{J}\eta}$,\,\, $\ensuremath{\mathrm{B_s^0}\rightarrow\mathrm{J}\eta}$,\,\, $\ensuremath{\mathrm{B_d^0}\rightarrow\mathrm{J}\pi^0}$ and $\ensuremath{\mathrm{B_s^0}\rightarrow\mathrm{J}\pi^0}$. The data sample consisted of more than three and half million hadronic $\ensuremath{\mathrm {Z}}$ decays collected by the L3 experiment at LEP from 1991 through 1995. No candidate events have been observed for any of the modes thus determining upper limits at 90\% confidence level: $3.2\times 10^{-4}$ on $\mathrm{Br}(\ensuremath{\mathrm{B_d^0}\rightar row\mathrm{J}\pi^0)}$ and the first experimental limits: \begin{eqnarray*} \mathrm{Br}(\ensuremath{\mathrm{B_d^0}\rightarrow \mathrm{J}\eta}) & & 1.2\times 10^{-3},\\ \mathrm{Br}(\ensuremath{\m athrm{B_s^0}\rightarrow\mathrm{J}\eta}) & & 3.8\times 10^{-3},\\ \mathrm{Br}(\ensuremath{\mathrm{B_s^0}\rightarrow\mathrm {J}\pi^0}) & & 1.2\times 10^{-3}.\\ \end{eqnarray*}