Absolute energy distribution studies in stars and comets

Abstract

Through the visible window of the earth's atmosphere, we measured portions of stellar continuum of six classical cepheids and a few Be stars, using a Hilger and Watts spectrum scanner at the Cassegrain focus of the one metre telescope. These observations after calibration give monochromatic magnitudes at various wavelengths. Based on these observations, effective temperature of classical cepheids at their various phases of light cycle were estimated be comparing the observed absolute energy distribution in visible region with the stellar model atmospheres. These temperatures were used to established an effective temperature and colour relation. Similar technique was used to estimate effective temperatures of a few bright Be stars. Spectrophotometry of many bright comets was done using the same instruments to estimate the production rates and column densities of the molecular species giving emission bands.