Measurement of the photon polarization in Λb0→Λγ decays

Aaij, R. et al. (2022) Measurement of the photon polarization in Λb0→Λγ decays. Physical Review D, 105(5), L051104. (doi: 10.1103/PhysRevD.105.L051104)

Abstract

The photon polarization in b → s γ transitions is measured for the first time in radiative b -baryon decays exploiting the unique spin structure of Λ 0 b → Λ γ decays. A data sample corresponding to an integrated luminosity of 6     fb − 1 collected by the LHCb experiment in p p collisions at a center-of-mass energy of 13 TeV is used. The photon polarization is measured to be α γ = 0.8 2 + 0.17 + 0.04 − 0.26 − 0.13 , where the first uncertainty is statistical and the second systematic. This result is in agreement with the Standard Model prediction and previous measurements in b -meson decays. Charge-parity breaking effects are studied for the first time in this observable and found to be consistent with C P symmetry.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Seman Bobulska, Dana and Alexander, Dr Michael and Soler, Professor Paul and Schiller, Dr Manuel and McHugh, Niall and Friday, David and Douglas, Lauren and Coombs, George and Spradlin, Dr Patrick and Cooke, Miss Naomi and Petric, Dr Marko and Eklund, Prof Lars and Longstaff, Iain Richard
• 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., 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 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, I., Bhasin, S., Bhom, J., Bian, L., Bieker, M. S., Bifani, S., Billoir, P., 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., Borghi, S., Borisyak, M., Borsato, M., Borsuk, J. T., Bouchiba, S. A., Bowcock, T. J. V., Boyer, A., Bozzi, C., Bradley, M. J., Braun, S., Brea Rodriguez, A., Brodzicka, J., Brossa Gonzalo, A., Brundu, D., Buonaura, A., Buonincontri, L., Burke, A. T., Burr, C., Bursche, A., Butkevich, A., Butter, J. S., Buytaert, J., Byczynski, W., Cadeddu, S., Cai, H., Calabrese, R., Calefice, L., Calero Diaz, L., Cali, S., Calladine, R., Calvi, M., Calvo Gomez, M., Camargo Magalhaes, P., Campana, P., Campoverde Quezada, A. F., Capelli, S., Capriotti, L., Carbone, A., Carboni, G., Cardinale, R., Cardini, A., Carli, I., Carniti, P., Carus, L., Carvalho Akiba, K., Casais Vidal, A., Casse, G., Cattaneo, M., Cavallero, G., Celani, S., Cerasoli, J., Cervenkov, D., Chadwick, A. J., Chapman, M. G., Charles, M., Charpentier, P., Chatzikonstantinidis, G., Chavez Barajas, C. A., Chefdeville, M., Chen, C., Chen, S., Chernov, A., Chobanova, V., Cholak, S., Chrzaszcz, M., Chubykin, A., Chulikov, V., Ciambrone, P., Cicala, M. F., Cid Vidal, X., Ciezarek, G., Clarke, P. E. L., Clemencic, M., Cliff, H. V., Closier, J., Cobbledick, J. L., Coco, V., Coelho, J. A. B., Cogan, J., Cogneras, E., Cojocariu, L., Collins, P., Colombo, T., Congedo, L., Contu, A., Cooke, N., Coombs, G., Corredoira, I., Corti, G., Costa Sobral, C. M., Couturier, B., Craik, D. C., Crkovská, J., Cruz Torres, M., Currie, R., Da Silva, C. L., Dadabaev, S., Dai, L., Dall’Occo, E., Dalseno, J., D’Ambrosio, C., Danilina, A., d’Argent, P., Davies, J. E., Davis, A., De Aguiar Francisco, O., De Bruyn, K., De Capua, S., De Cian, M., De Miranda, J. M., De Paula, L., De Serio, M., De Simone, D., De Simone, P., De Vellis, F., de Vries, J. A., Dean, C. T., Debernardis, F., Decamp, D., Dedu, V., Del Buono, L., Delaney, B., Dembinski, H.-P., Dendek, A., Denysenko, V., Derkach, D., Deschamps, O., Desse, F., Dettori, F., Dey, B., Di Cicco, A., Di Nezza, P., Didenko, S., Dieste Maronas, L., Dijkstra, H., Dobishuk, V., Dong, C., Donohoe, A. M., Dordei, F., dos Reis, A. C., Douglas, L., Dovbnya, A., Downes, A. G., Dudek, M. W., Dufour, L., Duk, V., Durante, P., Durham, J. M., Dutta, D., Dziurda, A., Dzyuba, A., Easo, S., Egede, U., Egorychev, V., Eidelman, S., Eisenhardt, S., Ek-In, S., Eklund, L., Ely, S., Ene, A., Epple, E., Escher, S., Eschle, J., Esen, S., Evans, T., Falabella, A., Fan, J., Fan, Y., Fang, B., Farry, S., Fazzini, D., Féo, M., Fernandez Prieto, A., Fernez, A. D., Friday, D., Longstaff, I. R., McHugh, N., Petric, M., Schiller, M., Soler, P., and Spradlin, P.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Physical Review D
• Publisher: American Physical Society
• ISSN: 2470-0010
• ISSN (Online): 2470-0029
• Published Online: 23 March 2022
• Copyright Holders: Copyright © 2022 CERN, for the LHCb Collaboration
• First Published: First published in Physical Review D 105(5): L051104
• Publisher Policy: Reproduced under a Creative Commons License