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arXiv · 1803.09503

V2676 Oph: Estimating physical parameters of a moderately fast nova

Ashish Raj·M. Pavana·U. S. Kamath·G. C. Anupama·F. M. Walter
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Abstract

Using our previously reported observations, we derive some physical parameters of the moderately fast nova V2676 Ophiuchi 2012 # 1. The best-fit CLOUDY model of the nebular spectrum obtained on 2015 May 8 shows a hot white dwarf source with Tbb = 1.0 x 10^{5} K having a luminosity of 1.0 x 10^{38} ergs/s. Our abundance analysis shows that the ejecta are significantly enhanced relative to solar, He/H = 2.14, O/H = 2.37, S/H = 6.62 and Ar/H = 3.25. The ejecta mass is estimated to be 1.42 x 10^{-5} Msun. The nova showed a pronounced dust formation phase after 90 days from discovery. The J-H and H-K colors were very large as compared to other molecule- and dust-forming novae in recent years. The dust temperature and mass at two epochs have been estimated from spectral energy distribution (SED) fits to infrared photometry.

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Ashish Raj, M. Pavana, U. S. Kamath, G. C. Anupama, F. M. Walter. 2018-03-26. V2676 Oph: Estimating physical parameters of a moderately fast nova. https://doi.org/10.32023/0001-5237/68.1.4

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