Hello all,
Hi Joan,
Thanks for your comment !
The monitoring of the details visible in the Halpha line profile of this nova is really exciting: we need an expert to understand their evolution !
It's also very interesting to see the parallel evolution of the Halpha and HeI 6678 A lines you mention : I look forward to seeing your next echelle spectrum with your remarkable Nou T spectrograph !!
Hi Matthieu,
To try to understand the origin of these details and whether they are noise or not, it seems to me that you could look at the individual 1D spectra that are generated in ISIS (@pro1.fit, @pro2.fit, @pro3.fit, ...) for the final 1D spectrum processing.
Are these details visible on each of them ?
I was thinking, for example, of the FeII lines at 4923, 5018 and 5169 A and, in particular, of the SiII lines at 6347 and 6371 A. The latter seem to be well visible in your spectrum of August 26 !
As usual, I continue the monitoring of the Halpha line of the Nova Cas 2021 and there is, again, some change since August 27 !
So, here is my new comparison between my two last spectra of the Halpha line of Nova Cas 2021 at high resolution on August 31 at 22 h 02 TU (resolution of 19064, JJ = 2459458.4182, 9 x 600s) and on September 2 at 21 h 55 TU (resolution of 18580, JJ = 2459460.4134, 12 x 600s) obtained with my LHIRES III (grating of 2400 lines / mm) and the previous ones in August :
- Halpha line of Nova Cas 2021 on August 1st, 8th, 12th, 13th, 21th, 25th, 27th, 31th and on September 2nd 2021
- novacas2021_20210902_Halpha_Christophe Boussin.png (60.66 KiB) Viewed 5818 times
Since August 31, a peak located at + 785 km/s emerges on the profile of the Halpha line (it seems to be already visible on the spectrum of August 27).
On the spectrum of September 2, the evolution of the peak is particularly obvious !
- Halpha line of Nova Cas 2021 on August 1st, 8th, 12th, 13th, 21th, 25th, 27th, 31th and on September 2nd 2021 (zoom)
- novacas2021_20210902_Halpha_zoom_Christophe Boussin.png (82.92 KiB) Viewed 5818 times
(Johnson V : green squares)
- Light curve of the Nova CAS 2021 (AAVSO)
Clear skies to all !!
Christophe BOUSSIN