spectro-aras.com

From ATel, P Cygni profiles have been detected
New observations at all resolution are songly encouraged, for those who have clear skies (so not for me ...)
All the best,

François



Title: A New Active Stage of the Symbiotic Star CH Cygni
Author: Takashi Iijima (INAF Astronomical Observatory of Padova, Asiago
Station)
Queries: takashi.iijima@oapd.inaf.it
Posted: 4 Mar 2017; 04:22 UT
Subjects:Optical, Cataclysmic Variable, Star, Variables

The spectral variation of the symbiotic star CH Cygni has been monitored at Asiago Astrophysical Observatory using the 1.22m Galileo telescope.
Recently, P Cygni type high velocity absorption components appeared on the H I Balmer lines, which were not seen in early December 2016. The blue-shifts of the absorption components from the narrow emission ones were -1890 km/s on 2017 Jan. 24.20 UT, -2040 km/s on Feb. 15.19, -2240 km/s on Feb.
26.13,
and -1930 km/s on March 3.16. The equivalent widths of those of H_beta on respective date were 0.16, 0.17, 0.32, and 0.09 nm, and their FWHMs were roughly 0.6 nm. This object has probably entered a new active stage.

Spectrum acquired this morning
I don't detected any P Cyg profile

François Teyssier

Francois,

The ATEL mentions H-beta.
However, we have already seen many times - at least in 2015, see the forum movies - temporary appearance and quick changes (like every 10 minute) in H-beta, while it was almost invisible in H-alpha. So I'm rather unsure that it's new.

- Peter

EDIT:
See http://www.spectro-aras.com/forum/viewt ... 5&start=30 , H-beta variations at 2015.07.05, but there are others. While H-alpha absorptions vary only a little (e.g. my serie on 2015.07.04).
I've also taken asdb_chcyg_20170226_166 last weekend too, but seeing no relevant H-alpha absorption either.

Peter,

The ATel mentions P Cyg on HI Balmer lines, not only H beta

I also checked the other lines, notably H beta and found nothing relevant, apart from the well known variations of central absorption at ~ 70 km/s and equally well known variations in the broad pedestrial (-200 to -600 km/s)

I do agree that the variations are more obvious on H beta, as H alpha is not the better line for astrophysical analysis.

Well, more spectra are needed ...

François

Ch Cyg at H alpha for March 19th. Same result - no sign of a P Cyg profile.
Tim

Thank you for the confirmation, Tim

François

Hello,

Is a new graphic of CH Cyg.

Regards, Joan.

Nice spectrum, but title to be corrected, Joan (SU Lyn)

François

Thanks a lot François.

Unfortantely as I said to you the last time that we wrote, I made another mistake with the name of a star. Maybe this won't be the last time.

Amicalemet, Joan.

CH Cyg taken last night and évolution from may 2016 to April 2017