“…The efficiency calibration of a Si (Li) detector in the energy range of 5-60 keV using radioactive sources has been reported by Verma (1985). A modified theoretical model for calculating the efficiency of a Si (Li) detector has been presented by Garg et al (1987) while the comparison of experimental efficiencies for different Si(Li) detectors in the energy range, 4.5-17.5 keV has been made by Yap et al (1987).…”