학술논문

A new algorithm for identifying the flavour of $B_s^0$ mesons at LHCb
Document Type
Working Paper
Author
LHCb collaborationAaij, R.Beteta, C. AbellánAdeva, B.Adinolfi, M.Affolder, A.Ajaltouni, Z.Akar, S.Albrecht, J.Alessio, F.Alexander, M.Ali, S.Alkhazov, G.Cartelle, P. AlvarezAlves Jr, A. A.Amato, S.Amerio, S.Amhis, Y.An, L.Anderlini, L.Andreassi, G.Andreotti, M.Andrews, J. E.Appleby, R. B.Gutierrez, O. AquinesArchilli, F.d'Argent, P.Artamonov, A.Artuso, M.Aslanides, E.Auriemma, G.Baalouch, M.Bachmann, S.Back, J. J.Badalov, A.Baesso, C.Baldini, W.Barlow, R. J.Barschel, C.Barsuk, S.Barter, W.Batozskaya, V.Battista, V.Bay, A.Beaucourt, L.Beddow, J.Bedeschi, F.Bediaga, I.Bel, L. J.Bellee, V.Belloli, N.Belyaev, I.Ben-Haim, E.Bencivenni, G.Benson, S.Benton, J.Berezhnoy, A.Bernet, R.Bertolin, A.Betti, F.Bettler, M. -O.van Beuzekom, M.Bifani, S.Billoir, P.Bird, T.Birnkraut, A.Bizzeti, A.Blake, T.Blanc, F.Blouw, J.Blusk, S.Bocci, V.Bondar, A.Bondar, N.Bonivento, W.Borgheresi, A.Borghi, S.Borisyak, M.Borsato, M.Bowcock, T. J. V.Bowen, E.Bozzi, C.Braun, S.Britsch, M.Britton, T.Brodzicka, J.Brook, N. H.Buchanan, E.Burr, C.Bursche, A.Buytaert, J.Cadeddu, S.Calabrese, R.Calvi, M.Gomez, M. CalvoCampana, P.Perez, D. CamporaCapriotti, L.Carbone, A.Carboni, G.Cardinale, R.Cardini, A.Carniti, P.Carson, L.Akiba, K. CarvalhoCasse, G.Cassina, L.Garcia, L. CastilloCattaneo, M.Cauet, Ch.Cavallero, G.Cenci, R.Charles, M.Charpentier, Ph.Chatzikonstantinidis, G.Chefdeville, M.Chen, S.Cheung, S. -F.Chiapolini, N.Chrzaszcz, M.Vidal, X. CidCiezarek, G.Clarke, P. E. L.Clemencic, M.Cliff, H. V.Closier, J.Coco, V.Cogan, J.Cogneras, E.Cogoni, V.Cojocariu, L.Collazuol, G.Collins, P.Comerma-Montells, A.Contu, A.Cook, A.Coombes, M.Coquereau, S.Corti, G.Corvo, M.Couturier, B.Cowan, G. A.Craik, D. C.Crocombe, A.Torres, M. CruzCunliffe, S.Currie, R.D'Ambrosio, C.Dall'Occo, E.Dalseno, J.David, P. N. Y.Davis, A.Francisco, O. De AguiarDe Bruyn, K.De Capua, S.De Cian, M.De Miranda, J. M.De Paula, L.De Simone, P.Dean, C. -T.Decamp, D.Deckenhoff, M.Del Buono, L.Déléage, N.Demmer, M.Derkach, D.Deschamps, O.Dettori, F.Dey, B.Di Canto, A.Di Ruscio, F.Dijkstra, H.Donleavy, S.Dordei, F.Dorigo, M.Suárez, A. DosilDovbnya, A.Dreimanis, K.Dufour, L.Dujany, G.Dungs, K.Durante, P.Dzhelyadin, R.Dziurda, A.Dzyuba, A.Easo, S.Egede, U.Egorychev, V.Eidelman, S.Eisenhardt, S.Eitschberger, U.Ekelhof, R.Eklund, L.Rifai, I. ElElsasser, Ch.Ely, S.Esen, S.Evans, H. M.Evans, T.Falabella, A.Färber, C.Farley, N.Farry, S.Fay, R.Fazzini, D.Ferguson, D.Albor, V. FernandezFerrari, F.Rodrigues, F. FerreiraFerro-Luzzi, M.Filippov, S.Fiore, M.Fiorini, M.Firlej, M.Fitzpatrick, C.Fiutowski, T.Fleuret, F.Fohl, K.Fol, P.Fontana, M.Fontanelli, F.Forshaw, D. C.Forty, R.Frank, M.Frei, C.Frosini, M.Fu, J.Furfaro, E.Torreira, A. GallasGalli, D.Gallorini, S.Gambetta, S.Gandelman, M.Gandini, P.Gao, Y.Pardiñas, J. GarcíaTico, J. GarraGarrido, L.Gascon, D.Gaspar, C.Gavardi, L.Gazzoni, G.Gerick, D.Gersabeck, E.Gersabeck, M.Gershon, T.Ghez, Ph.Gianì, S.Gibson, V.Girard, O. G.Giubega, L.Gligorov, V. V.Göbel, C.Golubkov, D.Golutvin, A.Gomes, A.Gotti, C.Gándara, M. GrabalosaDiaz, R. GracianiCardoso, L. A. GranadoGraugés, E.Graverini, E.Graziani, G.Grecu, A.Griffith, P.Grillo, L.Grünberg, O.Gui, B.Gushchin, E.Guz, Yu.Gys, T.Hadavizadeh, T.Hadjivasiliou, C.Haefeli, G.Haen, C.Haines, S. C.Hall, S.Hamilton, B.Han, X.Hansmann-Menzemer, S.Harnew, N.Harnew, S. T.Harrison, J.He, J.Head, T.Heijne, V.Heister, A.Hennessy, K.Henrard, P.Henry, L.Morata, J. A. Hernandovan Herwijnen, E.Heß, M.Hicheur, A.Hill, D.Hoballah, M.Hombach, C.Hulsbergen, W.Humair, T.Hushchyn, M.Hussain, N.Hutchcroft, D.Hynds, D.Idzik, M.Ilten, P.Jacobsson, R.Jaeger, A.Jalocha, J.Jans, E.Jawahery, A.John, M.Johnson, D.Jones, C. R.Joram, C.Jost, B.Jurik, N.Kandybei, S.Kanso, W.Karacson, M.Karbach, T. M.Karodia, S.Kecke, M.Kelsey, M.Kenyon, I. R.Kenzie, M.Ketel, T.Khairullin, E.Khanji, B.Khurewathanakul, C.Kirn, T.Klaver, S.Klimaszewski, K.Kochebina, O.Kolpin, M.Komarov, I.Koopman, R. F.Koppenburg, P.Kozeiha, M.Kravchuk, L.Kreplin, K.Kreps, M.Krocker, G.Krokovny, P.Kruse, F.Krzemien, W.Kucewicz, W.Kucharczyk, M.Kudryavtsev, V.Kuonen, A. K.Kurek, K.Kvaratskheliya, T.Lacarrere, D.Lafferty, G.Lai, A.Lambert, D.Lanfranchi, G.Langenbruch, C.Langhans, B.Latham, T.Lazzeroni, C.Gac, R. Levan Leerdam, J.Lees, J. -P.Lefèvre, R.Leflat, A.Lefrançois, J.Cid, E. LemosLeroy, O.Lesiak, T.Leverington, B.Li, Y.Likhomanenko, T.Liles, M.Lindner, R.Linn, C.Lionetto, F.Liu, B.Liu, X.Loh, D.Longstaff, I.Lopes, J. H.Lucchesi, D.Martinez, M. LucioLuo, H.Lupato, A.Luppi, E.Lupton, O.Lusardi, N.Lusiani, A.Machefert, F.Maciuc, F.Maev, O.Maguire, K.Malde, S.Malinin, A.Manca, G.Mancinelli, G.Manning, P.Mapelli, A.Maratas, J.Marchand, J. F.Marconi, U.Benito, C. MarinMarino, P.Marks, J.Martellotti, G.Martin, M.Martinelli, M.Santos, D. MartinezVidal, F. MartinezTostes, D. MartinsMassacrier, L. M.Massafferri, A.Matev, R.Mathad, A.Mathe, Z.Matteuzzi, C.Mauri, A.Maurin, B.Mazurov, A.McCann, M.McCarthy, J.McNab, A.McNulty, R.Meadows, B.Meier, F.Meissner, M.Melnychuk, D.Merk, M.Merli, AMichielin, EMilanes, D. A.Minard, M. -N.Mitzel, D. S.Rodriguez, J. MolinaMonroy, I. A.Monteil, S.Morandin, M.Morawski, P.Mordà, A.Morello, M. J.Moron, J.Morris, A. B.Mountain, R.Muheim, F.Müller, D.Müller, J.Müller, K.Müller, V.Mussini, M.Muster, B.Naik, P.Nakada, T.Nandakumar, R.Nandi, A.Nasteva, I.Needham, M.Neri, N.Neubert, S.Neufeld, N.Neuner, M.Nguyen, A. D.Nguyen-Mau, C.Niess, V.Nieswand, S.Niet, R.Nikitin, N.Nikodem, T.Novoselov, A.O'Hanlon, D. P.Oblakowska-Mucha, A.Obraztsov, V.Ogilvy, S.Okhrimenko, O.Oldeman, R.Onderwater, C. J. G.Rodrigues, B. OsorioGoicochea, J. M. OtaloraOtto, A.Owen, P.Oyanguren, A.Palano, A.Palombo, F.Palutan, M.Panman, J.Papanestis, A.Pappagallo, M.Pappalardo, L. L.Pappenheimer, C.Parker, W.Parkes, C.Passaleva, G.Patel, G. D.Patel, M.Patrignani, C.Pearce, A.Pellegrino, A.Penso, G.Altarelli, M. PepePerazzini, S.Perret, P.Pescatore, L.Petridis, K.Petrolini, A.Petruzzo, M.Olloqui, E. PicatostePietrzyk, B.Pikies, M.Pinci, D.Pistone, A.Piucci, A.Playfer, S.Casasus, M. PloPoikela, T.Polci, F.Poluektov, A.Polyakov, I.Polycarpo, E.Popov, A.Popov, D.Popovici, B.Potterat, C.Price, E.Price, J. D.Prisciandaro, J.Pritchard, A.Prouve, C.Pugatch, V.Navarro, A. PuigPunzi, G.Qian, W.Quagliani, R.Rachwal, B.Rademacker, J. H.Rama, M.Pernas, M. RamosRangel, M. S.Raniuk, I.Raven, G.Redi, F.Reichert, S.Reis, A. C. dosRenaudin, V.Ricciardi, S.Richards, S.Rihl, M.Rinnert, K.Molina, V. RivesRobbe, P.Rodrigues, A. B.Rodrigues, E.Lopez, J. A. RodriguezPerez, P. RodriguezRogozhnikov, A.Roiser, S.Romanovsky, V.Vidal, A. RomeroRonayne, J. W.Rotondo, M.Ruf, T.Valls, P. RuizSilva, J. J. SaboridoSagidova, N.Saitta, B.Guimaraes, V. SalustinoMayordomo, C. SanchezSedes, B. SanmartinSantacesaria, R.Rios, C. SantamarinaSantimaria, M.Santovetti, E.Sarti, A.Satriano, C.Satta, A.Saunders, D. M.Savrina, D.Schael, S.Schiller, M.Schindler, H.Schlupp, M.Schmelling, M.Schmelzer, T.Schmidt, B.Schneider, O.Schopper, A.Schubiger, M.Schune, M. -H.Schwemmer, R.Sciascia, B.Sciubba, A.Semennikov, A.Serra, N.Serrano, J.Sestini, L.Seyfert, P.Shapkin, M.Shapoval, I.Shcheglov, Y.Shears, T.Shekhtman, L.Shevchenko, V.Shires, A.Siddi, B. G.Coutinho, R. Silvade Oliveira, L. SilvaSimi, G.Sirendi, M.Skidmore, N.Skwarnicki, T.Smith, E.Smith, I. T.Smith, J.Smith, M.Snoek, H.Sokoloff, M. D.Soler, F. J. P.Soomro, F.Souza, D.De Paula, B. SouzaSpaan, B.Spradlin, P.Sridharan, S.Stagni, F.Stahl, M.Stahl, S.Stefkova, S.Steinkamp, O.Stenyakin, O.Stevenson, S.Stoica, S.Stone, S.Storaci, B.Stracka, S.Straticiuc, M.Straumann, U.Sun, L.Sutcliffe, W.Swientek, K.Swientek, S.Syropoulos, V.Szczekowski, M.Szumlak, T.T'Jampens, S.Tayduganov, A.Tekampe, T.Tellarini, G.Teubert, F.Thomas, C.Thomas, E.van Tilburg, J.Tisserand, V.Tobin, M.Todd, J.Tolk, S.Tomassetti, L.Tonelli, D.Topp-Joergensen, S.Tournefier, E.Tourneur, S.Trabelsi, K.Traill, M.Tran, M. T.Tresch, M.Trisovic, A.Tsaregorodtsev, A.Tsopelas, P.Tuning, N.Ukleja, A.Ustyuzhanin, A.Uwer, U.Vacca, C.Vagnoni, V.Valenti, G.Vallier, A.Gomez, R. VazquezRegueiro, P. VazquezSierra, C. VázquezVecchi, S.van Veghel, M.Velthuis, J. J.Veltri, M.Veneziano, G.Vesterinen, M.Viaud, B.Vieira, D.Diaz, M. VieitesVilasis-Cardona, X.Volkov, V.Vollhardt, A.Voong, D.Vorobyev, A.Vorobyev, V.Voß, C.de Vries, J. A.Waldi, R.Wallace, C.Wallace, R.Walsh, J.Wang, J.Ward, D. R.Watson, N. K.Websdale, D.Weiden, A.Whitehead, M.Wicht, J.Wilkinson, G.Wilkinson, M.Williams, M.Williams, M. P.Williams, T.Wilson, F. F.Wimberley, J.Wishahi, J.Wislicki, W.Witek, M.Wormser, G.Wotton, S. A.Wraight, K.Wright, S.Wyllie, K.Xie, Y.Xu, Z.Yang, Z.Yu, J.Yuan, X.Yushchenko, O.Zangoli, M.Zavertyaev, M.Zhang, L.Zhang, Y.Zhelezov, A.Zhokhov, A.Zhong, L.Zhukov, V.Zucchelli, S.
Source
Journal of Instrumentation 11 (2016) P05010
Subject
High Energy Physics - Experiment
Language
Abstract
A new algorithm for the determination of the initial flavour of $B_s^0$ mesons is presented. The algorithm is based on two neural networks and exploits the $b$ hadron production mechanism at a hadron collider. The first network is trained to select charged kaons produced in association with the $B_s^0$ meson. The second network combines the kaon charges to assign the $B_s^0$ flavour and estimates the probability of a wrong assignment. The algorithm is calibrated using data corresponding to an integrated luminosity of 3 fb$^{-1}$ collected by the LHCb experiment in proton-proton collisions at 7 and 8 TeV centre-of-mass energies. The calibration is performed in two ways: by resolving the $B_s^0$-$\bar{B}_s^0$ flavour oscillations in $B_s^0 \to D_s^- \pi^+$ decays, and by analysing flavour-specific $B_{s 2}^{*}(5840)^0 \to B^+ K^-$ decays. The tagging power measured in $B_s^0 \to D_s^- \pi^+$ decays is found to be $(1.80 \pm 0.19({\rm stat}) \pm 0.18({\rm syst}))$\%, which is an improvement of about 50\% compared to a similar algorithm previously used in the LHCb experiment.
Comment: All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-056.html