Observation of $$ {\Lambda}_b^0 $$ → D+pπ−π− and $$ {\Lambda}_b^0 $$ → D+pπ−π− decays

• Published in: The journal of high energy physics 2022-03, Vol.2022 (3), Article 153
• Main Authors: Aaij, R., Abdelmotteleb, A. S. W., Abellán Beteta, C., Abudinén, F., Ackernley, T., Adeva, B., Adinolfi, M., Afsharnia, H., Agapopoulou, C., Aidala, C. A., Aiola, S., Ajaltouni, Z., Akar, S., Albrecht, J., Alessio, F., Alexander, M., Alfonso Albero, A., Aliouche, Z., Alkhazov, G., Alvarez Cartelle, P., Amato, S., Amey, J. L., Amhis, Y., An, L., Anderlini, L., Andersson, M., Andreianov, A., Andreotti, M., Archilli, F., Artamonov, A., Artuso, M., Arzymatov, K., Aslanides, E., Atzeni, M., Audurier, B., Bachmann, S., Bachmayer, M., Back, J. J., Baladron Rodriguez, P., Balagura, V., Baldini, W., Baptista de Souza Leite, J., Barbetti, M., Barlow, R. J., Barsuk, S., Barter, W., Bartolini, M., Baryshnikov, F., Basels, J. M., Bashir, S., Bassi, G., Batsukh, B., Battig, A., Bay, A., Beck, A., Becker, M., Bedeschi, F., Bediaga, I., Beiter, A., Belavin, V., Belin, S., Bellee, V., Belous, K., Belov, I., Belyaev, I., Bencivenni, G., Ben-Haim, E., Berezhnoy, A., Bernet, R., Berninghoff, D., Bernstein, H. C., Bertella, C., Bertolin, A., Betancourt, C., Betti, F., Bezshyiko, Ia, Bhasin, S., Bhom, J., Bian, L., Bieker, M. S., Biesuz, N. V., Bifani, S., Billoir, P., Biolchini, A., Birch, M., Bishop, F. C. R., Bitadze, A., Bizzeti, A., Bjørn, M., Blago, M. P., Blake, T., Blanc, F., Blusk, S., Bobulska, D., Boelhauve, J. A., Boente Garcia, O., Boettcher, T., Boldyrev, A., Bondar, A., Bondar, N.
• Format: Article
• Language: English
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP03(2022)153

The multihadron decays $$ {\Lambda}_b^0 $$ Λ b 0 → D + pπ−π− and $$ {\Lambda}_b^0 $$ Λ b 0 → D * + pπ−π− are observed in data corresponding to an integrated luminosity of 3 fb − 1 , collected in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV by the LHCb detector. Using the decay $$ {\Lambda}_b^0 $$ Λ b 0 → $$ {\Lambda}_c^{+} $$ Λ c + π + π − π − as a normalisation channel, the ratio of branching fractions is measured to be $$ \frac{\mathcal{B}\left({\Lambda}_b^0\to {D}^{+}p{\pi}^{-}{\pi}^{-}\right)}{\mathcal{B}\left({\Lambda}_b^0\to {\Lambda}_c^0{\pi}^{+}{\pi}^{-}{\pi}^{-}\right)}\times \frac{\mathcal{B}\left({D}^{+}\to {K}^{-}{\pi}^{+}{\pi}^{+}\right)}{\mathcal{B}\left({\Lambda}_c^0\to {pK}^{-}{\pi}^{-}\right)}=\left(5.35\pm 0.21\pm 0.16\right)\%, $$ B Λ b 0 → D + p π − π − B Λ b 0 → Λ c 0 π + π − π − × B D + → K − π + π + B Λ c 0 → pK − π − = 5.35 ± 0.21 ± 0.16 % , where the first uncertainty is statistical and the second systematic. The ratio of branching fractions for the $$ {\Lambda}_b^0 $$ Λ b 0 → D *+ pπ − π − and $$ {\Lambda}_b^0 $$ Λ b 0 → D + pπ − π − decays is found to be $$ \frac{\mathcal{B}\left({\Lambda}_b^0\to {D}^{\ast +}p{\pi}^{-}{\pi}^{-}\right)}{\mathcal{B}\left({\Lambda}_b^0\to {D}^{+}p{\pi}^{-}{\pi}^{-}\right)}\times \left(\mathcal{B}\left({D}^{\ast +}\to {D}^{+}{\pi}^0\right)+\mathcal{B}\left({D}^{\ast +}\to {D}^{+}\gamma \right)\right)=\left(61.3\pm 4.3\pm 4.0\right)\%. $$ B Λ b 0 → D ∗ + p π − π − B Λ b 0 → D + p π − π − × B D ∗ + → D + π 0 + B D ∗ + → D + γ = 61.3 ± 4.3 ± 4.0 % .