Measurement of CP violation parameters and polarisation fractions in B s 0 → J / ψ K ¯ ∗ 0 $$ {\mathrm{B}}_{\mathrm{s}}^0\to \mathrm{J}/\psi {\overline{\mathrm{K}}}^{\ast 0} $$ decays

Measurement of CP violation parameters and polarisation fractions in B s 0 → J / ψ K ¯ ∗ 0 $$ {\mathrm{B}}_{\mathrm{s}}^0\to \mathrm{J}/\psi {\overline{\mathrm{K}}}^{\ast 0} $$ decays