DR. SOMA DE

The speaker uses Supernova Ia and 21cm radiation coming from neutral hydrogen from early universe as probes of cosmology. In this talk, in the first half, she will describe her ongoing work on SN Ia and how one can calculate the progenetor metallicity from the observed light curves and spectra. She will use stellar atmosphere code PHOENIX (co-developed by Hauschildt and Baron, 1999) to calculate the spectra and lightcurve of a white dwarf explosion by solving the radiative transfer equation, rate equation for different species and energy conservation equations simultaneously. In the second phase of her talk, she will discuss her ongoing research on 21cm radiation coming from high redshift universe prior to star formation. She will explain how and through which channels different gravity scenarios or dark energy models will affect the 21cm absorption profile.