Moessbauer spectrometer and spectrometry

In a moessbauer spectrometer for obtaining moessbauer spectra by a moessbauer spectrometry, comprising a Co-57 radiation source for irradiating gamma rays to a steel specimen and a gamma ray detector for detecting gamma rays absorbed with resonation by the specimen, in which a detection portion of the gamma ray detector comprises CdTe (cadmium telluride). The detection includes a case of detecting gamma rays absorbed with resonation when passing through the specimen by detecting gamma rays which are remained while not being resonated or absorbed in addition to a case of detecting gamma rays released again after absorbed with resonation once to the specimen. Namely, it includes so called reflection method and permeation method. Physical properties of steel materials used under radiation circumstance of various energy levels such as in nuclear power plants can be measured, and degradation of two phase stainless steel pipes to be used in the facility by thermal embrittlement can be measured previously, which greatly contributes to the improvement of safety of the facility. (N.H.)