LHCb CollaborationAaij, R.Adeva, B.Adinolfi, M.Ajaltouni, Z.Akar, S.Albrecht, J.Alessio, F.Alexander, M.Alfonso Albero, A.Ali, S.Alkhazov, G.Cartelle, P. AlvarezAmato, S.Amerio, S.Amhis, Y.An, L.Anderlini, L.Andreassi, G.Andreotti, M.Andrews, J. E.Appleby, R. B.Archilli, F.D'Argent, P.Romeu, J. ArnauArtamonov, A.Artuso, M.Aslanides, E.Atzeni, M.Auriemma, G.Baalouch, M.Babuschkin, I.Bachmann, S.Back, J. J.Badalov, A.Baesso, C.Baker, S.Balagura, V.Baldini, W.Baranov, A.Barlow, R. J.Barschel, C.Barsuk, S.Barter, W.Baryshnikov, F.Batozskaya, V.Battista, V.Bay, A.Beaucourt, L.Beddow, J.Bedeschi, F.Bediaga, I.Beiter, A.Bel, L. J.Beliy, N.Bellee, V.Belloli, N.Belous, K.Belyaev, I.Ben-Haim, E.Bencivenni, G.Benson, S.Beranek, S.Berezhnoy, A.Bernet, R.Berninghoff, D.Bertholet, E.Bertolin, A.Betancourt, C.Betti, F.Bettler, M. -O.Van Beuzekom, M.Bezshyiko, Ia.Bifani, S.Billoir, P.Birnkraut, A.Bizzeti, A.Bjorn, M.Blake, T.Blanc, F.Blusk, S.Bocci, V.Boettcher, T.Bondar, A.Bondar, N.Bordyuzhin, I.Borghi, S.Borisyak, M.Borsato, M.Bossu, F.Boubdir, M.Bowcock, T. J. V.Bowen, E.Bozzi, C.Braun, S.Britton, T.Brodzicka, J.Brundu, D.Buchanan, E.Burr, C.Bursche, A.Buytaert, J.Byczynski, W.Cadeddu, S.Cai, H.Calabrese, R.Calladine, R.Calvi, M.Calvo Gomez, M.Camboni, A.Campana, P.Perez, D. H. CamporaCapriotti, L.Carbone, A.Carboni, G.Cardinale, R.Cardini, A.Carniti, P.Carson, L.Carvalho Akiba, K.Casse, G.Cassina, L.Cattaneo, M.Cavallero, G.Cenci, R.Chamont, D.Chapman, M. G.Charles, M.Charpentier, Ph.Chatzikonstantinidis, G.Chefdeville, M.Chen, S.Cheung, S. F.Chitic, S. -G.Chobanova, V.Chrzaszcz, M.Chubykin, A.Ciambrone, P.Cid Vidal, X.Ciezarek, G.Clarke, P. E. L.Clemencic, M.Cliff, H. V.Closier, J.Cogan, J.Cogneras, E.Cogoni, V.Cojocariu, L.Collins, P.Colombo, T.Comerma-Montells, A.Contu, A.Cook, A.Coombs, G.Coquereau, S.Corti, G.Corvo, M.Sobral, C. M. CostaCouturier, B.Cowan, G. A.Craik, D. C.Crocombe, A.Cruz Torres, M.Currie, R.D'Ambrosio, C.Da Cunha Marinho, F.Dall'Occo, E.Dalseno, J.Davis, A.Francisco, O. De AguiarDe Capua, S.De Cian, M.De Miranda, J. M.De Paula, L.De Serio, M.De Simone, P.Dean, C. T.Decamp, D.Del Buono, L.Dembinski, H. -P.Demmer, M.Dendek, A.Derkach, D.Deschamps, O.Dettori, F.Dey, B.Di Canto, A.Di Nezza, P.Dijkstra, H.Dordei, F.Dorigo, M.Dosil Suarez, A.Douglas, L.Dovbnya, A.Dreimanis, K.Dufour, L.Dujany, G.Durante, P.Dzhelyadin, R.Dziewiecki, M.Dziurda, A.Dzyuba, A.Easo, S.Ebert, M.Egede, U.Egorychev, V.Eidelman, S.Eisenhardt, S.Eitschberger, U.Ekelhof, R.Eklund, L.Ely, S.Esen, S.Evans, H. M.Evans, T.Falabella, A.Farley, N.Farry, S.Fazzini, D.Federici, L.Ferguson, D.Fernandez, G.Declara, P. FernandezFernandez Prieto, A.Ferrari, F.Ferreira Rodrigues, F.Ferro-Luzzi, M.Filippov, S.Fini, R. A.Fiorini, M.Firlej, M.Fitzpatrick, C.Fiutowski, T.Fleuret, F.Fohl, K.Fontana, M.Fontanelli, F.Forshaw, D. C.Forty, R.Lima, V. FrancoFrank, M.Frei, C.Fu, J.Funk, W.Furfaro, E.Faerber, C.Gabriel, E.Gallas Torreira, A.Galli, D.Gallorini, S.Gambetta, S.Gandelman, M.Gandini, P.Gao, Y.Garcia Martin, L. M.Garcia Pardinas, J.Tico, J. GarraGarrido, L.Garsed, P. J.Gascon, D.Gaspar, C.Gavardi, L.Gazzoni, G.Gerick, D.Gersabeck, E.Gersabeck, M.Gershon, T.Ghez, Ph.Giani, S.Gibson, V.Girard, O. G.Giubega, L.Gizdov, K.Gligorov, V. V.Golubkov, D.Golutvin, A.Gomes, A.Gorelov, I. V.Gotti, C.Govorkova, E.Grabowski, J. P.Graciani Diaz, R.Cardoso, L. A. GranadoGrauges, E.Graverini, E.Graziani, G.Grecu, A.Greim, R.Griffith, P.Grillo, L.Gruber, L.Cazon, B. R. GrubergGruenberg, O.Gushchin, E.Guz, Yu.Gys, T.Gobel, C.Hadavizadeh, T.Hadjivasiliou, C.Haefeli, G.Haen, C.Haines, S. C.Hamilton, B.Han, X.Hancock, T. H.Hansmann-Menzemer, S.Harnew, N.Harnew, S. T.Hasse, C.Hatch, M.He, J.Hecker, M.Heinicke, K.Heister, A.Hennessy, K.Henrard, P.Henry, L.Van Herwijnen, E.Hess, M.Hicheur, A.Hill, D.Hombach, C.Hopchev, P. H.Hu, W.Huard, Z. C.Hulsbergen, W.Humair, T.Hushchyn, M.Hutchcroft, D.Ibis, P.Idzik, M.Ilten, P.Jacobsson, R.Jalocha, J.Jans, E.Jawahery, A.Jiang, F.John, M.Johnson, D.Jones, C. R.Joram, C.Jost, B.Jurik, N.Kandybei, S.Karacson, M.Kariuki, J. M.Karodia, S.Kazeev, N.Kecke, M.Keizer, F.Kelsey, M.Kenzie, M.Ketel, T.Khairullin, E.Khanji, B.Khurewathanakul, C.Kirn, T.Klaver, S.Klimaszewski, K.Klimkovich, T.Koliiev, S.Kolpin, M.Kopecna, R.Koppenburg, P.Kosmyntseva, A.Kotriakhova, S.Kozeiha, M.Kravchuk, L.Kreps, M.Kress, F.Krokovny, P.Kruse, F.Krzemien, W.Kucewicz, W.Kucharczyk, M.Kudryavtsev, V.Kuonen, A. K.Kvaratskheliya, T.Lacarrere, D.Lafferty, G.Lai, A.Lanfranchi, G.Langenbruch, C.Latham, T.Lazzeroni, C.Le Gac, R.Leflat, A.Lefrancois, J.Lefevre, R.Lemaitre, F.Lemos Cid, E.Leroy, O.Lesiak, T.Leverington, B.Li, P. -R.Li, T.Li, Y.Li, Z.Likhomanenko, T.Lindner, R.Lionetto, F.Lisovskyi, V.Liu, X.Loh, D.Loi, A.Longstaff, I.Lopes, J. H.Lucchesi, D.Luchinsky, A.Lucio Martinez, M.Luo, H.Lupato, A.Luppi, E.Lupton, O.Lusiani, A.Lyu, X.Machefert, F.Maciuc, F.Macko, V.Mackowiak, P.Maddrell-Mander, S.Maev, O.Maguire, K.Maisuzenko, D.Majewski, M. W.Malde, S.Malecki, B.Malinin, A.Maltsev, T.Manca, G.Mancinelli, G.Marangotto, D.Maratas, J.Marchand, J. F.Marconi, U.Marin Benito, C.Marinangeli, M.Marino, P.Marks, J.Martellotti, G.Martin, M.Martinelli, M.Martinez Santos, D.Martinez Vidal, F.Massacrier, L. M.Massafferri, A.Matev, R.Mathad, A.Mathe, Z.Matteuzzi, C.Mauri, A.Maurice, E.Maurin, B.Mazurov, A.Mccann, M.Mcnab, A.Mcnulty, R.Mead, J. V.Meadows, B.Meaux, C.Meier, F.Meinert, N.Melnychuk, D.Merk, M.Merli, A.Michielin, E.Milanes, D. A.Millard, E.Minard, M. -N.Minzoni, L.Mitzel, D. S.Mogini, A.Molina Rodriguez, J.Mombaecher, T.Monroy, I. A.Monteil, S.Morandin, M.Morello, M. J.Morgunova, O.Moron, J.Morris, A. B.Mountain, R.Muheim, F.Mulder, M.Mueller, D.Mueller, J.Mueller, K.Mueller, V.Naik, P.Nakada, T.Nandakumar, R.Nandi, A.Nasteva, I.Needham, M.Neri, N.Neubert, S.Neufeld, N.Neuner, M.Nguyen, T. D.Nguyen-Mau, C.Nieswand, S.Niet, R.Nikitin, N.Nikodem, T.Nogay, A.O'Hanlon, D. P.Oblakowska-Mucha, A.Obraztsov, V.Ogilvy, S.Oldeman, R.Onderwater, C. J. G.Ossowska, A.Otalora Goicochea, J. M.Owen, P.Oyanguren, A.Pais, P. R.Palano, A.Palutan, M.Papanestis, A.Pappagallo, M.Pappalardo, L. L.Parker, W.Parkes, C.Passaleva, G.Pastore, A.Patel, M.Patrignani, C.Pearce, A.Pellegrino, A.Penso, G.Altarelli, M. 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J.Sadykhov, E.Sagidova, N.Saitta, B.Salustino Guimaraes, V.Sanchez Mayordomo, C.Sanmartin Sedes, B.Santacesaria, R.Santamarina Rios, C.Santimaria, M.Santovetti, E.Sarpis, G.Sarti, A.Satriano, C.Satta, A.Saunders, D. M.Savrina, D.Schael, S.Schellenberg, M.Schiller, M.Schindler, H.Schmelling, M.Schmelzer, T.Schmidt, B.Schneider, O.Schopper, A.Schreiner, H. F.Schubiger, M.Schune, M. -H.Schwemmer, R.Sciascia, B.Sciubba, A.Semennikov, A.Sepulveda, E. S.Sergi, A.Serra, N.Serrano, J.Sestini, L.Seyfert, P.Shapkin, M.Shapoval, I.Shcheglov, Y.Shears, T.Shekhtman, L.Shevchenko, V.Siddi, B. G.Coutinho, R. SilvaSilva De Oliveira, L.Simi, G.Simone, S.Sirendi, M.Skidmore, N.Skwarnicki, T.Smith, E.Smith, I. T.Smith, J.Smith, M.Soares Lavra, L.Sokoloff, M. D.Soler, F. J. P.De Paula, B. SouzaSpaan, B.Spradlin, P.Sridharan, S.Stagni, F.Stahl, M.Stahl, S.Stefko, P.Stefkova, S.Steinkamp, O.Stemmle, S.Stenyakin, O.Stepanova, M.Stevens, H.Stone, S.Storaci, B.Stracka, S.Stramaglia, M. E.Straticiuc, M.Straumann, U.Sun, J.Sun, L.Sutcliffe, W.Swientek, K.Syropoulos, V.Szumlak, T.Szymanski, M.T'Jampens, S.Tayduganov, A.Tekampe, T.Tellarini, G.Teubert, F.Thomas, E.Van Tilburg, J.Tilley, M. J.Tisserand, V.Tobin, M.Tolk, S.Tomassetti, L.Tonelli, D.Toriello, F.Tourinho Jadallah Aoude, R.Tournefier, E.Traill, M.Tran, M. T.Tresch, M.Trisovic, A.Tsaregorodtsev, A.Tsopelas, P.Tully, A.Tuning, N.Ukleja, A.Usachov, A.Ustyuzhanin, A.Uwer, U.Vacca, C.Vagner, A.Vagnoni, V.Valassi, A.Valat, S.Valenti, G.Gomez, R. VazquezVazquez Regueiro, P.Vecchi, S.Van Veghel, M.Velthuis, J. J.Veltri, M.Veneziano, G.Venkateswaran, A.Verlage, T. A.Vernet, M.Vesterinen, M.Barbosa, J. V. VianaViaud, B.Vieira, D.Vieites Diaz, M.Viemann, H.Vilasis-Cardona, X.Vitti, M.Volkov, V.Vollhardt, A.Voneki, B.Vorobyev, A.Vorobyev, V.Voss, C.De Vries, J. A.Vazquez Sierra, C.Waldi, R.Wallace, C.Wallace, R.Walsh, J.Wang, J.Ward, D. R.Wark, H. M.Watson, N. K.Websdale, D.Weiden, A.Weisser, C.Whitehead, M.Wicht, J.Wilkinson, G.Wilkinson, M.Williams, M.Williams, M. P.Williams, M.Williams, T.Wilson, F. F.Wimberley, J.Winn, M.Wishahi, J.Wislicki, W.Witek, M.Wormser, G.Wotton, S. A.Wraight, K.Wyllie, K.Xie, Y.Xu, M.Xu, Z.Yang, Z.Yang, Z.Yao, Y.Yin, H.Yu, J.Yuan, X.Yushchenko, O.Zarebski, K. A.Zavertyaev, M.Zhang, L.Zhang, Y.Zhelezov, A.Zheng, Y.Zhu, X.Zhukov, V.Zonneveld, J. B.Zucchelli, S.2018-01-152018-01-152018-01-15201710.1103/PhysRevLett.119.221801https://infoscience.epfl.ch/handle/20.500.14299/144114WOS:000416317900008The decays chi(c1) -> J/psi mu(+)mu(-) and chi(c1) -> J/psi mu(+)mu(-) are observed and used to study the resonance parameters of the chi(c1) and chi(c2) mesons. The masses of these states are measured to be m(chi(c1)) = 3510.71 +/- 0.04(stat) +/- 0.09(syst) MeV and m(chi(c2)) = 3556.10 +/- 0.06(stat) +/- 0.11(syst) MeV, where the knowledge of the momentum scale for charged particles dominates the systematic uncertainty. The momentum-scale uncertainties largely cancel in the mass difference m(chi(c2)) - m(chi(c1)) = 45.39 +/- 0.07(stat) +/- 0.03(syst) MeV. The natural width of the chi(c2) meson is measured to be Gamma(chi(c2)) = 2.10 +/- 0.20(stat) +/- 0.02(syst) MeV. These results are in good agreement with and have comparable precision to the current world averages.text::journal::journal article::research article