000 02250nab a2200325 c 4500
001 vtls000581790
003 RU-ToGU
005 20210922092454.0
007 cr |
008 170911|2017 xxu s a eng d
024 7 _a10.1103/PhysRevLett.118.092002
_2doi
035 _ato000581790
040 _aRU-ToGU
_brus
_cRU-ToGU
245 1 0 _aEvidence of two resonant structures in e+e- →π+π-hc
_cM. Ablikim, M. N. Achasov, S. Ahmed [et al.]
504 _aБиблиогр.: 41 назв.
520 3 _aThe cross sections of e+e−→π+π−hc at center-of-mass energies from 3.896 to 4.600 GeV are measured using data samples collected with the BESIII detector operating at the Beijing Electron Positron Collider. The cross sections are found to be of the same order of magnitude as those of e+e−→π+π−J/ψ and e+e−→π+π−ψ(2S), but the line shape is inconsistent with the Y states observed in the latter two modes. Two structures are observed in the e+e−→π+π−hc cross sections around 4.22 and 4.39  GeV/c2, which we call Y(4220) and Y(4390), respectively. A fit with a coherent sum of two Breit-Wigner functions results in a mass of (4218.4+5.5−4.50.9)  MeV/c2 and a width of (66.0+12.3−8.30.4)  MeV for the Y(4220), and a mass of (4391.5+6.3−6.81.0)  MeV/c2 and a width of (139.5+16.2−20.60.6)  MeV for the Y(4390), where the first uncertainties are statistical and the second ones systematic. The statistical significance of Y(4220) and Y(4390) is 10σ over one structure assumption.
653 _aBESIII, детектор
653 _aBEPCII, коллайдер
653 _aрезонансные структуры
655 4 _aстатьи в журналах
_9745982
700 1 _aAchasov, M. N.
_9117569
700 1 _aAhmed, S.
_9360310
700 1 _aChelkov, G. A.
_996983
700 1 _aAblikim, M.
_9117568
773 0 _tPhysical Review Letters
_d2017
_gVol. 118, № 9. P. 092002-1-092002-8
_x0031-9007
852 4 _aRU-ToGU
856 7 _uhttp://vital.lib.tsu.ru/vital/access/manager/Repository/vtls:000581790
908 _aстатья
999 _c425791