Journal of the physical society of japan vol:63 issue:7 pages:2453-2457
We report the first reliable observation of the tiny shifts of energy levels of a nucleus placed between two parallel metallic plates. We observed the absorption of the 81 keV gamma ray from Cs-133 induced by the beta-decay of Ba-133 in a *BaTiO3 compound. This Mossbauer experiment was carried out at 4.2 K with the absorber placed between two silicon plates with gold coating. The observed shifts are around 0.95 neV (equivalent to 0.007 mm/s) for the distance of about 2 mm between the two plates.