Formation and decay of the E1′ center and of its precursor

The E1′ center has been used for ESR dating of quartz with assuming that the signal intensity increases with natural radiation dose as those of other ESR signals do. However, this simple assumption is not necessarily correct. Formation and decay of the E1′ center are closely related with its precursor, diamagnetic oxygen vacancies. Gamma ray of large dose (>100 kGy) creates oxygen vacancies giving little dose rate effect, which, therefore, might be useful for dating of granites and high dose dosimetry.