On Purple Mountain Halpha observations of SS 433

TL;DR

This paper analyzes the stationary Halpha spectral line of SS 433 over multiple years, comparing data sets to assess the stability of spectral features linked to a circumbinary disk.

Contribution

It provides a comparative analysis of Halpha line structures over years and orbits, supporting the stability of spectral features attributed to a circumbinary disk.

Findings

Halpha line structures are consistent over years and orbits

Spectral features show persistence, indicating stability

Supports the circumbinary disk hypothesis

Abstract

In this brief note I draw attention to the structure of the stationary Halpha line as a function of orbital phase, using a data set compiled over some years. These data are compared with a set of nightly observations over some 2 orbits. The structures are very similar and this is highly relevant to the question of persistence and stability of spectral features which have been attributed to a circumbinary disk.