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Study of CKM angle $gamma$ sensitivity using flavor untagged $B^0_srightarrow tilde{D}^{(*)0}phi$ decays

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 نشر من قبل Xiaokang Zhou
 تاريخ النشر 2020
  مجال البحث
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A sensitivity study for the measurement of the CKM angle $gamma$ from $B^0_srightarrow tilde{D}^{(*)0}phi$ decays is performed using $D$ meson reconstructed in the quasi flavour-specific modes $Kpi$, $K3pi$, $Kpipi^0$, and CP-eigenstate modes $KK$ and $pipi$, where the notation $tilde{D}^0$ corresponds to a $D^0$ or a ${tilde{D}^0}$ meson. The LHCb experiment is taken as a use case. A statistical uncertainty of about $8-19^{circ}$ can be achieved with the $pp$ collision data collected by the LHCb experiment from year 2011 to 2018. The sensitivity to $gamma$ should be of the order $3-8^{circ}$ after accumulating 23invfb of $pp$ collision data by 2025, while it is expected to further improve with 300~fb$^{-1}$ by the second half of the 2030 decade. The accuracy depends on the strong parameters $r^{(*)}_{B}$ and ${delta^{(*)}_{B}}$, describing, together with $gamma$, the interference between the leading amplitudes of the $B^0_srightarrow tilde{D}^{(*)0}phi$ decays.



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