  Using data from proton-antiproton collisions at Ecms=1.96 TeV recorded by the
CDF II detector at the Fermilab Tevatron, we present evidence for the excited
resonance state Lambda_b* in its fully reconstructed decay mode to Lambda_b0
pi+ pi- where Lambda_b0 -->Lambda_c+ (-->proton K- pi+) pi-. The analysis is
based on a data sample corresponding to an integrated luminosity of 9.6/fb
collected by an online event selection based on tracks displaced from the
proton-antiproton interaction point. The local significance of the observed
signal is 4.6 Gaussian sigmas. while the significance of the signal for the
search region is 3.5 Gaussian sigmas. The mass of the observed state is found
to be 5919.5+-0.35+-1.72 MeV .
