Variation of fluxes of RR Tel emission lines measured in 2000 with respect to 1996

TL;DR

This study compares optical emission line fluxes of RR Tel from 1996 and 2000, revealing a general fading trend, especially in low ionization potential lines, and notes continued decrease in line widths over time.

Contribution

It provides new measurements of non-Fe+ emission line fluxes from 2000 and compares them with 1996 data, highlighting flux variations and line width evolution.

Findings

All emission lines show fading over time.

Fading is more pronounced in low ionization potential lines.

Line widths continue to decrease with time.

Abstract

The aim of this work is to make available unpublished non-Fe+ emission line fluxes from optical spectra of the symbiotic nova RR Tel which were taken in 2000, and to compare them with fluxes of the same lines from spectra taken in 1996. After leaving out blends and misidentifications, as well as the unreliable far-red and violet lines, we present the log (F2000/F1996) flux ratios for identified non-Fe+ lines. Mean values of log (F2000/F1996) for different ionization potential ranges of the ions producing the lines are shown separately for the permitted and forbidden lines. All means show fading, which is larger in the lowest range of ionization potential. Provisional interpretations are suggested. We also measured the values of FWHM in 2000; the previously known decrease with time of FWHM of lines due to the same ion has continued.