Lees J P, Poireau V, Tisserand V, Grauges E, Palano A, Eigen G, Brown D N, Kolomensky Yu G, Fritsch M, Koch H, Schroeder T, Cheaib R, Hearty C, Mattison T S, McKenna J A, So R Y, Blinov V E, Buzykaev A R, Druzhinin V P, Golubev V B, Kozyrev E A, Kravchenko E A, Onuchin A P, Serednyakov S I, Skovpen Yu I, Solodov E P, Todyshev K Yu, Lankford A J, Dey B, Gary J W, Long O, Eisner A M, Lockman W S, Panduro Vazquez W, Chao D S, Cheng C H, Echenard B, Flood K T, Hitlin D G, Kim J, Li Y, Lin D X, Miyashita T S, Ongmongkolkul P, Oyang J, Porter F C, Röhrken M, Huard Z, Meadows B T, Pushpawela B G, Sokoloff M D, Sun L, Smith J G, Wagner S R, Bernard D, Verderi M, Bettoni D, Bozzi C, Calabrese R, Cibinetto G, Fioravanti E, Garzia I, Luppi E, Santoro V, Calcaterra A, de Sangro R, Finocchiaro G, Martellotti S, Patteri P, Peruzzi I M, Piccolo M, Rotondo M, Zallo A, Passaggio S, Patrignani C, Shuve B J, Lacker H M, Bhuyan B, Mallik U, Chen C, Cochran J, Prell S, Gritsan A V, Arnaud N, Davier M, Le Diberder F, Lutz A M, Wormser G, Lange D J, Wright D M, Coleman J P, Gabathuler E, Hutchcroft D E, Payne D J, Touramanis C, Bevan A J, Di Lodovico F, Sacco R, Cowan G, Banerjee Sw, Brown D N, Davis C L, Denig A G, Gradl W, Griessinger K, Hafner A, Schubert K R, Barlow R J, Lafferty G D, Cenci R, Jawahery A, Roberts D A, Cowan R, Robertson S H, Seddon R M, Neri N, Palombo F, Cremaldi L, Godang R, Summers D J, Taras P, De Nardo G, Sciacca C, Raven G, Jessop C P, LoSecco J M, Honscheid K, Kass R, Gaz A, Margoni M, Posocco M, Simi G, Simonetto F, Stroili R, Akar S, Ben-Haim E, Bomben M, Bonneaud G R, Calderini G, Chauveau J, Marchiori G, Ocariz J, Biasini M, Manoni E, Rossi A, Batignani G, Bettarini S, Carpinelli M, Casarosa G, Chrzaszcz M, Forti F, Giorgi M A, Lusiani A, Oberhof B, Paoloni E, Rama M, Rizzo G, Walsh J J, Zani L, Smith A J S, Anulli F, Faccini R, Ferrarotto F, Ferroni F, Pilloni A, Piredda G, Bünger C, Dittrich S, Grünberg O, Heß M, Leddig T, Voß C, Waldi R, Adye T, Wilson F F, Emery S, Vasseur G, Aston D, Cartaro C, Convery M R, Dorfan J, Dunwoodie W, Ebert M, Field R C, Fulsom B G, Graham M T, Hast C, Innes W R, Kim P, Leith D W G S, Luitz S, MacFarlane D B, Muller D R, Neal H, Ratcliff B N, Roodman A, Sullivan M K, Va'vra J, Wisniewski W J, Purohit M V, Wilson J R, Randle-Conde A, Sekula S J, Ahmed H, Bellis M, Burchat P R, Puccio E M T, Alam M S, Ernst J A, Gorodeisky R, Guttman N, Peimer D R, Soffer A, Spanier S M, Ritchie J L, Schwitters R F, Izen J M, Lou X C, Bianchi F, De Mori F, Filippi A, Gamba D, Lanceri L, Vitale L, Martinez-Vidal F, Oyanguren A, Albert J, Beaulieu A, Bernlochner F U, King G J, Kowalewski R, Lueck T, Nugent I M, Roney J M, Sibidanov A, Sobie R J, Tasneem N, Gershon T J, Harrison P F, Latham T E, Prepost R, Wu S L
Laboratoire d'Annecy-le-Vieux de Physique des Particules (LAPP), Université de Savoie, CNRS/IN2P3, F-74941 Annecy-Le-Vieux, France.
Universitat de Barcelona, Facultat de Fisica, Departament ECM, E-08028 Barcelona, Spain.
Phys Rev Lett. 2020 Dec 11;125(24):241801. doi: 10.1103/PhysRevLett.125.241801.
We report on a precision measurement of the ratio R_{τμ}^{ϒ(3S)}=B(ϒ(3S)→τ^{+}τ^{-})/B(ϒ(3S)→μ^{+}μ^{-}) using data collected with the BABAR detector at the SLAC PEP-II e^{+}e^{-} collider. The measurement is based on a 28 fb^{-1} data sample collected at a center-of-mass energy of 10.355 GeV corresponding to a sample of 122 million ϒ(3S) mesons. The ratio is measured to be R_{τμ}^{ϒ(3S)}=0.966±0.008_{stat}±0.014_{syst} and is in agreement with the standard model prediction of 0.9948 within 2 standard deviations. The uncertainty in R_{τμ}^{ϒ(3S)} is almost an order of magnitude smaller than the only previous measurement.
我们报告了使用在SLAC PEP-II正负电子对撞机上的BABAR探测器收集的数据，对比率(R_{τμ}^{ϒ(3S)} = B(ϒ(3S)→τ^{+}τ^{-})/B(ϒ(3S)→μ^{+}μ^{-}))进行的精确测量。该测量基于在质心能量为10.355 GeV时收集的28(fb^{-1})数据样本，对应于1.22亿个(ϒ(3S))介子的样本。测得的比率为(R_{τμ}^{ϒ(3S)} = 0.966±0.008_{统计}±0.014_{系统})，并且在2个标准差内与标准模型预测的0.9948一致。(R_{τμ}^{ϒ(3S)})的不确定性比之前唯一的测量值小近一个数量级。
