New experimental limits on the alpha decays of lead isotopes
  For the first time a PbWO4 crystal was grown using ancient Roman lead and it was run as a cryogenic detector. Thanks to the simultaneous and independent read-out of heat and scintillation light, the detector was able to discriminate beta/gamma interactions with respect to alpha particles down to low energies. New more stringent limits on the alpha decays of the lead isotopes are presented. In particular a limit of T_{1/2} > 1.4*10^20 y at a 90% C.L. was evaluated for the alpha decay of 204Pb to 200Hg. 
J. W. Beeman, F. Bellini, L. Cardani, N. Casali, S. Di Domizio, E.   Fiorini, L. Gironi, S.S. Nagorny, S. Nisi, F. Orio, L. ...
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