Temperature dependence of the Moessbauer effect on Sn-119 doped metallic lead

After perfecting a technique to manufacture extremely pure, homogeneous, small-concentration Sn in Pb samples, we have measured the Debye-Waller factor over the temperature range of 4 to 300 K. Our data show some evidence of a line broadening between 4 and 50 K which may be accounted for by the spin-density wave model of lead proposed by A. Overhauser. Between 77 K and room temperature, we find a temperature dependence to the recoilless fraction consistent with a Debye model (Debye temperature = 107(2) K). Moreover, we find no evidence of a sudden precipitous fall-off of the recoilless fraction, as was reported by Schechter et al. in 1989. The origin of this difference is discussed. (orig.)