| In the standard quark model(SM), the XCJ (J=0,1,2) mesons are cc states in an L=1 configuration. As their production is suppressed in in e+e- collisions, they are not known well as the ?(3686) states. In 2009 and 2012, BESIII collected two large ?(3686) data samples. The sum of total ?(3686) events is about 4.48× 108. Since the radiative transition of ?(3686)??xCJ have large branching ratios of about 9%, it means there are sizable XCJ events in ?(3686) sample. This provides us a chance to investigate the XCJ decays. This work studies the ZCJ??? and xCJ??? decay process,which can help us to understand:1) the nature of the quark.2) the decay mechanism of XCJ mesons.3) the reasons for the violation of OZI rules in some decay processes.4) the mechanism of SU(3) symmetry breaking mechanism.5) the relationship between the rules of OZI and SU (3) flavor symmetry breaking rules and the wave function of ?? and ?? mesons.Based on 448M ?(3686) events collected with the BESIII detector in 2009 and 2012, a search for XCJ?PP (P=? or? )is performed. The signals of XC0???,XC2 ?? and XC2??? are observed for the first time with statistical significance of 13.4?,7.5?and 9.6?, respectively. Meanwhile, the measured branching ratio of XC0? ?? is improved. The corresponding branching ratios for XC0???,XC2??, XC0??? and XC2??? are determined to be (8.75±0.81±0.69)×10-5, (2.51±0.48±0. 21)±10-5,(2.16±0.03±0.15)×10-3 and (5.08±0.59±0.39)×10-5, respectively, where the first errors are statistical and the second errors are systematic. |
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