| Baryon spectroscopy is an important topic in the study of hadron physics.The baryon spec-trum provides important information for studying the structure of hadrons and the long-range interaction of QCD.The BES? experiment is a high-brightness particle physics experiment working at tau charm physical energy regions.Since the number in 2009,BES? has accumu-lated the largest samples of J/????3686?and so on in the world.The high statistic data on BES? is an ideal place to study and find baryon excited states,and has made many important discoveries and progress.Based on 4.48×108??3686?events collected with BES? detector at BEPCII,we present the measurement of ??3686???????,which is observed for the first time.The branching fraction is measured to be?3,42±0.34?stat.?±0.31?syst,??× 10-5.A hint that the mass and width of A*is 2.001±0.007 GeV and 0.036±0.014 GeV with the significance of 3.3?.And the upper limit branching fraction of B???3686??????*/????*???????is estimated to be 1.93 ×10-5 at 90%confidence level.Based on 1.31 × 109 J/?,events collected with BES? detector at BEPC? in 2009 and 2012,we present the measurement of J/???????,which is measured to be?19.93±0.38?atat.?±0.14?syst.??×10-5.Then we performed a search for ???? threshold enhancement in J/???????,and there is no obvious signal.And the upper limit on the Banching fraction of B?J/????2170?????????and B(J/??X?2239????????are 2.29×10-6 and 3.31×10-6,respectively. |
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