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Amplitude analysis of $B^{-} to D^{+} pi^{-} pi^{-}$ decays

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 نشر من قبل Mark Whitehead
 تاريخ النشر 2016
  مجال البحث
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The Dalitz plot analysis technique is used to study the resonant substructures of $B^{-} to D^{+} pi^{-} pi^{-}$ decays in a data sample corresponding to 3.0 ${rm fb}^{-1}$ of $pp$ collision data recorded by the LHCb experiment during 2011 and 2012. A model-independent analysis of the angular moments demonstrates the presence of resonances with spins 1, 2 and 3 at high $D^{+}pi^{-}$ mass. The data are fitted with an amplitude model composed of a quasi-model-independent function to describe the $D^{+}pi^{-}$ S-wave together with virtual contributions from the $D^{*}(2007)^{0}$ and $B^{*0}$ states, and components corresponding to the $D^{*}_{2}(2460)^{0}$, $D^{*}_{1}(2680)^{0}$, $D^{*}_{3}(2760)^{0}$ and $D^{*}_{2}(3000)^{0}$ resonances. The masses and widths of these resonances are determined together with the branching fractions for their production in $B^{-} to D^{+} pi^{-} pi^{-}$ decays. The $D^{+}pi^{-}$ S-wave has phase motion consistent with that expected due to the presence of the $D^{*}_{0}(2400)^{0}$ state. These results constitute the first observations of the $D^{*}_{3}(2760)^{0}$ and $D^{*}_{2}(3000)^{0}$ resonances.



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