Observations of gamma Cas and delta Sco
Posted: Wed Sep 14, 2016 8:53 am
Gamma Cas spectra of J. Guarro, T. Lester & P. Fosanelli enable to perform a new period analysis of the HeI 6678 ring-like structure around the primary and its V/R behaviour of the double-peak emission. The attached ongoing report 2016-09-13 confirms the consolidation of the periodicity of approx. 450 days. The investigation will be continued.
Also the intensive spectra contributions of delta Sco enable an interesting evaluation of the correlation between the equivalent width of Halpha to HeI 6678. For comparison see the publication: http://astrospectroscopy.de/media/files/IBVS-6179.pdf
It seems that the process of disk feeding, with the HeI 6678 EW as indicator, does have currently another quantitative relation to the disk growth than in the past. Fig. 7 of the mentioned paper shows that the current EW minimum of HeI 6678 could be the possible reason.
Any comments are welcome!
Ernst Pollmann
- gcas_HeI6678.png (83.68 KiB) Viewed 3177 times
- delsco_He6678 v. Halpha.png (142.28 KiB) Viewed 3177 times
Any comments are welcome!
Ernst Pollmann