Morpho-Kinematical Modelling of Nova Eridani 2009 (KT Eri)

TL;DR

This study models the shape and expansion of the nova KT Eridani's ejecta using morpho-kinematical techniques, revealing a dumbbell-shaped structure with specific geometric parameters, and discusses implications for the secondary star.

Contribution

It introduces a detailed morpho-kinematical model of KT Eridani's ejecta, providing new insights into its geometry and expansion velocity.

Findings

Dumbbell morphology with 4:1 axis ratio

Inclination angle of approximately 58 degrees

Maximum expansion velocity of about 2800 km/s

Abstract

Modelling the morphology of a nova outburst provides valuable information on the shaping mechanism in operation at early stages following the outburst. We performed morpho-kinematical studies, using {\sc shape}, of the evolution of the H\alpha\ line profile following the outburst of the nova KT Eridani. We applied a series of geometries in order to determine the morphology of the system. The best fit morphology was that of a dumbbell structure with a ratio between the major to minor axis of 4:1, with an inclination angle of 58$^{+6}_{-7}$ degrees and a maximum expansion velocity of 2800$\pm$200 km/s. Although, we found that it is possible to define the overall structure of the system, the radial density profile of the ejecta is much more difficult to disentangle. Furthermore, morphology implied here may also be consistent with the presence of an evolved secondary as suggested by various authors.