| Description |
The advent of instruments with better resolution and greater sensitivity have enabled us to obtain photometric
observations covering large part of the sky in several wavelength bands. The models of the Milky Way are
complimented well by these observations to predict different structure parameters of the Galaxy.
We have upgraded the Besancon model of stellar population synthesis, consisting of stars of thin disc,
thick disc and halo populations, from visible and near-infrared to ultraviolet wavelength bands of Galaxy
Evolution Explorer (GALEX) to make first study of the Galaxy using ultraviolet star counts.
It has been found that the model is consistent with observed UV data obtained from GALEX.
Based on model analysis, the white dwarfs of the disc and the blue horizontal
branch stars of the halo have been identified from the observed sample and then their respective
space densities have been estimated. The scale length and scale height of the thick disc using the space
density function and the exponential density law for the stars of intermediate Galactic latitude have been
determined. The model has been further developed to predict the star counts in UV passbands of the
forthcoming UVIT telescope on-board ASTROSAT mission which can be a potential tool for studying
the structure of our Galaxy from images in multiple far-UV and near-UV filters.
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