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تسجيل مستخدم جديدSearch for $B_c^+$ decays to two charm mesons
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A search for decays of $B_c^+$ mesons to two charm mesons is performed for the first time using data corresponding to an integrated luminosity of 3.0 fb$^{-1}$, collected by the LHCb experiment in $pp$ collisions at centre-of-mass energies of 7 and 8 TeV. The decays considered are $B_c^+to D^{(*)+}_{(s)} overline{D}^{(*)0}$ and $B_c^+to D^{(*)+}_{(s)} D^{(*)0}$, which are normalised to high-yield $B^+to D^+_{(s)} overline{D}^0$ decays. No evidence for a signal is found and limits are set on twelve $B_c^+$ decay modes.
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A data set corresponding to an integrated luminosity of $9 text{fb}^{-1}$ of proton-proton collisions collected by the LHCb experiment has been analysed to search for $B_c^+ to D^{(*)+}_{(s)} overset{scriptstyle (-)}{D}{}^{(*)0}$ decays. The decays a
re fully or partially reconstructed, where one or two missing neutral pions or photons from the decay of an excited charm meson are allowed. Upper limits for the branching fractions, normalised to $B^+$ decays to final states with similar topologies, are obtained for fourteen $B_c^+$ decay modes. For the decay $B_c^+ to D_s^+ {overline{D}}^0$, an excess with a significance of 3.4 standard deviations is found.
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Using data collected near the Ds*+ Ds- peak production energy Ecm = 4170 MeV by the CLEO-c detector, we study the decays of Ds+ mesons to two pseudoscalar mesons. We report on searches for the singly-Cabibbo-suppressed Ds+ decay modes K+ eta, K+ eta,
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