Search for new decays of the $\Lambda_b^0$ baryon at the LHCb experiment.

High statistics collected by the LHCb experiment between 2011 and 2018 in proton-proton (pp) collisions at the Large Hadron Colllider (LHC), jointly with the large cross-section of $b\bar{b}$ pairs production provides unique possibility for the search and study new decays of beauty hadrons. The results of search for new decays of the $\Lambda_b^0$ baryons are presented. In particular the decays $\Lambda_b^0 \to \Lambda_c^+p\bar{p}\pi^-$, $\Lambda_b^0 \to J/\psi\Lambda$, $\Lambda_b^0 \to \psi(2S)\Lambda$, $\Lambda_b^0 \to \psi(2S)p\pi^-$, $\Lambda_b^0 \to \chi_{c1}(3872)pK^-$ and $\Lambda_b^0 \to \Lambda\gamma$ are found and branching fraction ratios measurement for these decays are done. Also the study of the $\Lambda_b^0\pi^+\pi^-$ systems led to the observation of two new excited $\Lambda_b^0$ states, denoted as $\Lambda_b(6146)^0$ and $\Lambda_b(6152)^0$, are found.