Theoretical study in the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mover accent="true"><mml:mrow><mml:mi>B</mml:mi></mml:mrow><mml:mrow><mml:mo stretchy="false">¯</mml:mo></mml:mrow></mml:mover></mml:mrow><mml:mrow><mml:mn>0</mml:mn></mml:mrow></mml:msup><mml:mo stretchy="false">→</mml:mo><mml:mi>J</mml:mi><mml:mo stretchy="false">/</mml:mo><mml:mi>ψ</mml:mi><mml:msup><mml:mrow><mml:mover accent="true"><mml:mrow><mml:mi>K</mml:…

We study the decay processes of ${\overline{B}}^{0}\ensuremath{\rightarrow}J/\ensuremath{\psi}{\overline{K}}^{*0}{K}^{0}$ and ${\overline{B}}^{0}\ensuremath{\rightarrow}J/\ensuremath{\psi}{f}_{1}(1285)$ to analyze ${f}_{1}(1285)$ resonance. By calculation within chiral unitary approach where resonance is dynamically generated from ${K}^{*}\overline{K}\ensuremath{-}\mathrm{c}.\mathrm{c}.$ interaction, we find that ${\overline{K}}^{*0}{K}^{0}$ invariant mass distribution has a clear broad peak. Such peak been understood as signal ${f}_{1}(1285)$. Finally, obtain theoretical result ${R}_{t}={\mathrm{\ensuremath{\Gamma}}}_{{\overline{B}}^{0}\ensuremath{\rightarrow}J/\ensuremath{\psi}{\overline{K}}^{*0}{K}^{0}}/{\mathrm{\ensuremath{\Gamma}}}_{{\overline{B}}^{0}\ensuremath{\rightarrow}J/\ensuremath{\psi}{f}_{1}(1285)}$ which expected be compared with experimental data.