The Nebulosity and Distance of the Cepheid RS Puppis

TL;DR

This paper models the nebulosity around Cepheid RS Puppis as an equatorial disc at a specific angle, using phase-lag observations and a distance derived from period-luminosity relations.

Contribution

It provides a new interpretation of RS Pup's surrounding nebulosity as an equatorial disc based on phase-lag data and distance estimates.

Findings

Nebulosity modeled as an equatorial disc at 8.1 degrees inclination.

Phase-lag observations fit well with the disc model.

Implications for understanding Cepheid environments briefly discussed.

Abstract

Adopting a distance for RS Pup derived from a period-luminosity relation based on Cepheid parallaxes, it is shown that the phase-lag observations of the surrounding nebulosity by Kervella et al. are well fitted by a model of an equatorial disc at an angle of 8.1 $\pm$ 0.6 degrees to the plane of the sky. The astrophysical implications of this are briefly mentioned.