Studies of $\Lambda^0_{\mathrm{b}} \rightarrow \mathrm{J}/\psi \Lambda$ production in $pp$ collisions at $\sqrt{s}$ = 7 TeV

The $\Lambda^0_{\mathrm{b}} \rightarrow \mathrm{J}/\psi \Lambda$ production cross-section is measured with the LHCb detector in inelastic $pp$ collisions at a centre-of-mass energy of $\sqrt{s}$ = 7 TeV. Using 36.4 pb$^{-1}$ of data recorded in 2010, the cross-section for the region with rapidity 2.2 < $y$ < 4.5 and transverse momentum $p_T < 13.0 \rm{GeV}/c$ is found to be $\sigma (pp \rightarrow \Lambda^0_{\mathrm{b} } X) \cal{B} (\Lambda^0_{\mathrm{b} } \rightarrow \mathrm{J}/ \psi \Lambda) = 4.19 \pm 0.61 \mathrm{(stat)} \pm 0.37 \mathrm{(syst)}$ nb for the baryon and $\sigma(pp \to \overline{\Lambda}^0_{\mathrm{b}} X) \cal{B} (\overline{\Lambda}^0_{\mathrm{b}} \rightarrow \mathrm{J }/\psi \Lambda) = 2.63 \pm 0.48 \mathrm{(stat)} \pm 0.27 \mathrm{(syst)}$ nb for the antibaryon decay.