Observation of a new structure near 10.75 GeV in the energy dependence of the e$^{+}$e$^{−}$→ ϒ (nS)π$^{+}$π$^{−}$ (n = 1, 2, 3) cross sections

R. Mizuk , A. Bondar , I. Adachi , H. Aihara , D.M. Asner , V. Aulchenko , T. Aushev , R. Ayad , I. Badhrees , S. Bahinipati , A.M. Bakich , P. Behera , C. Beleño , M. Berger , V. Bhardwaj , T. Bilka , J. Biswal , A. Bozek , M. Bračko , T.E. Browder , M. Campajola , L. Cao , D. Červenkov , A. Chen , B.G. Cheon , K. Chilikin , H.E. Cho , K. Cho , S.-K. Choi , Y. Choi , D. Cinabro , S. Cunliffe , N. Dash , G. De Nardo , F. Di Capua , S. Di Carlo (1) , Z. Doležal , T.V. Dong , S. Eidelman , D. Epifanov , J.E. Fast , T. Ferber , B.G. Fulsom , V. Gaur , A. Garmash , A. Giri , P. Goldenzweig , B. Golob , O. Grzymkowska , T. Hara , O. Hartbrich , K. Hayasaka , H. Hayashii , W.-S. Hou , T. Iijima , K. Inami , G. Inguglia , A. Ishikawa , R. Itoh , M. Iwasaki , Y. Iwasaki , W.W. Jacobs , Y. Jin , D. Joffe , K.K. Joo , K.H. Kang , G. Karyan , T. Kawasaki , H. Kichimi , D.Y. Kim , H.J. Kim , K.T. Kim , S.H. Kim , K. Kinoshita , P. Kodyš , S. Korpar , D. Kotchetkov , P. Križan , R. Kroeger , P. Krokovny , T. Kuhr , R. Kumar , A. Kuzmin , J.S. Lange , J.Y. Lee , S.C. Lee , L.K. Li , L. Li Gioi , J. Libby , K. Lieret , D. Liventsev , T. Luo , J. Macnaughton , C. Macqueen , M. Masuda , T. Matsuda , D. Matvienko , M. Merola , H. Miyata , G.B. Mohanty , T. Mori , R. Mussa , T. Nakano , M. Nakao , K.J. Nath , Z. Natkaniec , M. Nayak , M. Niiyama , N.K. Nisar , S. Nishida , K. Nishimura , S. Ogawa , S.L. Olsen , H. Ono , Y. Onuki , P. Oskin , W. Ostrowicz , P. Pakhlov , G. Pakhlova , B. Pal , T. Pang , S. Pardi , S.-H. Park , S. Paul , T.K. Pedlar , R. Pestotnik , L.E. Piilonen , V. Popov , E. Prencipe , M. Ritter , A. Rostomyan , G. Russo , Y. Sakai , M. Salehi , S. Sandilya , T. Sanuki , V. Savinov , O. Schneider , G. Schnell , J. Schueler , C. Schwanda , Y. Seino , K. Senyo , O. Seon , M.E. Sevior , V. Shebalin , C.P. Shen , J.-G. Shiu , B. Shwartz , A. Sokolov , E. Solovieva , M. Starič , J.F. Strube , M. Sumihama , T. Sumiyoshi , W. Sutcliffe , M. Takizawa , U. Tamponi , K. Tanida , F. Tenchini , K. Trabelsi (1) , T. Uglov , Y. Unno , S. Uno , P. Urquijo , Y. Usov , S.E. Vahsen , R. van Tonder , G. Varner , A. Vinokurova , B. Wang , C.H. Wang , M.-Z. Wang , P. Wang , E. Won , S.B. Yang , H. Ye , C.Z. Yuan , Y. Yusa , Z.P. Zhang , V. Zhilich , V. Zhukova

1 LAL - Laboratoire de l'Accélérateur Linéaire

We report a new measurement of the e$^{+}$e$^{−}$→ ϒ(nS)π$^{+}$π$^{−}$ (n = 1, 2, 3) cross sections at energies from 10.52 to 11.02 GeV using data collected with the Belle detector at the KEKB asymmetric-energy e$^{+}$e$^{−}$ collider. We observe a new structure in the energy dependence of the cross sections, if described by a Breit-Wigner function its mass and width are found to be $ M=\left(10752.7\pm {5.9}_{-1.1}^{+0.7}\right)\mathrm{MeV}/{c}^2 $ and $ \Gamma =\left({35.5}_{-11.3\kern0.5em -3.3}^{+17.6+3.9}\right) $MeV, where the first error is statistical and the second is systematic. The global significance of the new structure including systematic uncertainty is 5.2 standard deviations. We also find evidence for the e$^{+}$e$^{−}$→ ϒ (1S)π$^{+}$π$^{−}$ process at the energy 10.52 GeV, which is below the B$ \overline{B} $ threshold.

Mots clés: e+-e- Experiments; Quarkonium; Spectroscopy; talk: Torino 2019/05/13; electron positron: annihilation; electron positron: colliding beams; cross section: energy dependence; error: statistical; structure; Upsilon(9460): electroproduction; Upsilon(10020): electroproduction; Upsilon(10355): electroproduction; Breit-Wigner; mass: width; resonance: mass: measured; BELLE; KEK-B; channel cross section: measured; experimental results; electron positron --> Upsilon(9460) pi+ pi-; electron positron --> Upsilon(10020) pi+ pi-; electron positron --> Upsilon(10355) pi+ pi-; M092.1; M092.17; M092.18; M092.19; M092M; M092W; M093.1; M093.5; M093.6; M093.7; M093M; M093W; M243.2; M243.3; M243.4; M243.5; M243M; M243W

Domaines: Physique des Hautes Energies - Expérience [hep-ex]

R. Mizuk, A. Bondar, I. Adachi, H. Aihara, D.M. Asner, et al.. Observation of a new structure near 10.75 GeV in the energy dependence of the e$^{+}$e$^{−}$→ ϒ (nS)π$^{+}$π$^{−}$ (n = 1, 2, 3) cross sections. 13th International Workshop on Heavy Quarkonium, May 2019, Torino, Italy. pp.220, ⟨10.1007/JHEP10(2019)220⟩. ⟨hal-02178535⟩