Institute of Astronomy

A Spectroscopic Analysis and Modelling of the Recurrent Nova RS Ophicuchi 2006 Outburst

SpeakerTalk DateTalk Series
Anindita Mondal29 July 2016Binary Stars Talks

Abstract

Novae are close binary systems consisting of a white dwarf as the primary star and a red-giant or main sequence star as the secondary. They are mainly of two types, classical and recurrent. Here, we present an analysis of elemental abundances of ejecta of recurrent nova RS Oph using optical and NIR spectrum during 2006 outburst (12 February, 2006) taken from 2m HCT and 1.2m Mt Abu observatory. We use CLOUDY photoionization code to generate synthetic spectra by varying several parameters. We used χ2 (chi-square) minimization technique to fit multiple epochs of emission line spectra and obtained the best fit model parameters. These parameters are compatible with a hot white dwarf source with log(Blackbody Temperature) of 4.45 – 6.4 K and roughly constant log(Luminosity) of 36.9 – 37.1 erg/s. From the analysis, we find the following abundances (by number) of elements with respect to solar: He/He⊙ = 1.5 – 2.5, N/N⊙ = 10 - 12, O/O⊙ = 0.7 – 5.0, Ne/Ne⊙ = 0.5 – 2.0, Si/Si⊙ = 0.3 – 0.5, Fe/Fe⊙ = 0.7 – 3.8, Ar/Ar⊙ = 4.0 – 5.5, and Al/Al⊙ = 0.9 – 1.1, Ni/Ni⊙ = 1.5 – 2.0. We also estimate an ejected mass in the range of 3.4 - 4.9 x 10^(−6) M⊙ which is consistent with observational results. 

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