Measurement of the ratio of branching fractions of the decays ${\Lambda }_b^0\to \psi (2S)\Lambda$ and ${\Lambda }_b^0\to J/\psi \Lambda$

LHCb Collaboration, R. Aaij, B. Adeva +799

Using $pp$ collisions corresponding to 3${\text{fb}}^{-1}$ integrated luminosity, recorded by the LHCb experiment at centre-of-mass energies of 7 and 8$\text{TeV}$, the ratio of…