A pre 2020-21 season update

Home Forums Spectroscopy Request for monitoring of X Per A pre 2020-21 season update

Robin Leadbeater

There are now over 230 spectra in the BAA spectroscopic database. Thanks to all contributors ! Continuing monitoring on a nominal 2 week basis during the next season is requested.  The following is a quick analysis of a selection of the available spectra.

The fall in EW of both the H alpha and He 6680 lines plateaued during January 2020 and remained constant up to the last recorded spectra on 2020-04-06 so there was no complete loss of the disc, though the He line in particular became very weak at just -0.4A EW

A snapshot of 5 heliocentric corrected line profiles during the monitoring period (marked A-E on the EW plots) shows the complex evolution of the lines and although the EW was approximately constant from Jan to April 2020, the line shape continued to evolve.

Although noisy due to the weakness of the line, there are significant differences in the He 6680 line profile compared with the H alpha line with higher radial velocity features particularly on the red edge.

Here is the AAVSO V mag light curve for the same period. There is no obvious correlation