Table 1.

Optimized selection criteria for the signal decay mode ${\mathrm{\Lambda }}_{\text{b}}^0\to \text{J}/\mathrm{\psi }{\mathrm{\Xi }}^{-}{\text{K}}^{+}$. The first two requirements are applied using the momenta before the corresponding mass constraint

Variable	Selection
$|m(\text{p}{\mathrm{\pi }}^{-})-m_{\text{PDG}}(\mathrm{\Lambda })|$	<8 MeV
$|m(\mathrm{\Lambda }{\mathrm{\pi }}^{-})-m_{\text{PDG}}({\mathrm{\Xi }}^{-})|$	<6 MeV
$p_{\text{T}}({\mathrm{\Lambda }}_{\text{b}}^0)$	>11.5 GeV
$p_{\text{T}}(\text{J}/\mathrm{\psi })$	>6.5 GeV
$p_{\text{T}}({\mathrm{\Xi }}^{-})$	>2.6 GeV
$p_{\text{T}}(\mathrm{\Lambda })$	>2.2 GeV
$p_{\text{T}}({\text{K}}^{+})$	>1.2 GeV
${\mathrm{\mu }}^{+}{\mathrm{\mu }}^{-}{\mathrm{\Xi }}^{-}{\text{K}}^{+}$ vertex fit probability	>5%
$\mathrm{\Lambda }{\mathrm{\pi }}^{-}$ vertex fit probability	>5%
$\text{p}{\mathrm{\pi }}^{-}$ vertex fit probability	>1%
${\mathrm{\Xi }}^{-}$ vertex displacement from ${\mathrm{\Lambda }}_{\text{b}}^0$ vertex	>3 s.d.
$\mathrm{\Lambda }$ vertex displacement from ${\mathrm{\Xi }}^{-}$ vertex	>0 s.d.
${\mathrm{\Lambda }}_{\text{b}}^0$ vertex displacement from PV	>3 s.d.
Angle between ${\mathrm{\Xi }}^{-}$ momentum and displacement	<0.0447 rad
Angle between $\mathrm{\Lambda }$ momentum and displacement	<0.14 rad
Angle between ${\mathrm{\Lambda }}_{\text{b}}^0$ momentum and displacement	<0.0447 rad
PV impact parameter for pion from ${\mathrm{\Xi }}^{-}$ decay	>0.4 s.d.
PV impact parameter for kaon	>0.4 s.d.