Observation of the doubly charmed baryon
arXiv:1707.01621 · doi:10.1103/PhysRevLett.119.112001
Abstract
A highly significant structure is observed in the mass spectrum, where the baryon is reconstructed in the decay mode . The structure is consistent with originating from a weakly decaying particle, identified as the doubly charmed baryon . The difference between the masses of the and states is measured to be , and the mass is then determined to be , where the last uncertainty is due to the limited knowledge of the mass. The state is observed in a sample of proton-proton collision data collected by the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.7 , and confirmed in an additional sample of data collected at 8 TeV.
arXiv commentAll figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2017-018.html
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