The 2010 nova outburst of the symbiotic Mira V407 Cyg

TL;DR

The 2010 nova outburst of V407 Cyg was a fast He/N nova embedded in a dense Mira wind, with ejecta deceleration and ionization effects studied through optical and infrared observations.

Contribution

This paper provides detailed observational analysis of the 2010 nova outburst in V407 Cyg, highlighting its similarities to RS Oph and the interaction with the Mira wind.

Findings

Ejecta decelerated from 2760 km/s to 200 km/s over 196 days.

Ionization of the Mira wind occurred within 4 days.

The Mira wind remained largely neutral and unperturbed during the outburst.

Abstract

The nova outburst experienced in 2010 by the symbiotic binary Mira V407 Cyg has been extensively studied at optical and infrared wavelengths with both photometric and spectroscopic observations. This outburst, reminiscent of similar events displayed by RS Oph, can be described as a very fast He/N nova erupting while being deeply embedded in the dense wind of its cool giant companion. The hard radiation from the initial thermonuclear flash ionizes and excites the wind of the Mira over great distances (recombination is observed on a time scale of 4 days). The nova ejecta is found to progressively decelerate with time as it expands into the Mira wind. This is deduced from line widths which change from a FWHM of 2760 km/s on day +2.3 to 200 km/s on day +196. The wind of the Mira is massive and extended enough for an outer neutral and unperturbed region to survive at all outburst phases.