Finally processed some lo-res spectra.
Been clouded out since the 12th Dec. Just waiting on some clear skies to obtain further spectra, R=1000, using the Spectra-L200 with 300 l/mm grating.
Seem to have lost the attachment......
Still clouded out in Melbourne, but a short exposure (one 3sec sub!!) from Jon Powles (in Canberra) shows a DRAMATIC increase in the Ha emission!!!!
Very interesting spectra.....
Finally got an hour of clear weather.
Used the Spectra-L200 with a 300 l/mm grating, R=1000
The region around the Hb continues to show strong Fe emission.
Still processing the Ha, but it appears to have reduced in intensity.
Jon Powles' spectrum is excellent with a SA.
Ken, note that at this stage there can't be [OIII] line a high energy line (~ 45 eV) ; [OIII] will appear later at the bengining of the nebular phase. The wavelenghts of these lines are 4363, 4959 and 5007. Noting at 463 nm
See for instance line identification for Nova Del 23013 on http://www.astrosurf.com/aras/novae/Nova2013Del-2.html
at the same stage. The spectral developement is very similar.
Thanks Ken and Francois!
I've got an L200 on order. Here's hoping it arrives before the nova fades too much. But according to the visual observers it appears to be brightening again.
BTW Francois, I'm trying to register for the ARAS spectroscopy forum but I can't get a reply. Do you know who I should contact?
Here are some results for review and discussion... Using the Spectra-L200/300 on the Genesis...
I have a medium res around Hb (showing P Cygni?) and the He and Fe emissions (look at the shape of the peaks - absorption?)
Moved across towards the Na region - again some profile detail... Finally around the Ha (again some P Cygni?) - the emission is still so strong, I zoomed into show some of the underlying detail....
Processed with BASS Project. Feedback welcome....
Some med res (R=1600) from the 28th Dec.
The P Cygni profiles at Ha and Hb show a 1500-1600 Km/s wind.
Not too much change....
A spectrum of the Hb region.
The Hb and Fe line profiles see to be showing a "secondary" dips (P-Cygni??)
There's been no significant reduction in magnitude over the past few days, interesting!!
The second absorption feature you are seeing in your lines is likely to be from a source of absorption between you and the star. Since it just appeared, the best interpretation is probably an expaning shell of material or ejecta that has recently cooled to the point where the H atoms have recombined. Since the part of that shell is moving outward from the star, the part between you and it is moving toward you... so it is blue shifted from the rest wavelength of the emission.
Finally caught up with the backlog!
Some nova spectra from 31st to 5th Jan.
Changed the grating to a 1200 l/mm and now achieve R=4040
The P-Cyg profiles still dominate the Hb/ Fe region.
I've run a velocity chart on Hb (rest =4861A), this shows the largest feature is at 1600Km/s!
Comment/ feedback welcome.
Managed to get some spectra last night.
The regions around Ha and Hb show the recent changes to the P-Cyg profiles ( now three absorption features?), some central absorption in the emission and the Fe lines are getting very complex.
Image aquisition and pre-processing by AstroArt, BASS project for the profiles.
The latest AAVSO Newsletter is out. I searched and could not find any mention of spectroscopy. It would have been nice if at least there were mentioned some plans, but nothing that I could find. I have seen some very interesting nova spectra submitted. It is strange the AAVSO has nothing to say on those. While I have not been able to get spectra on those novae I do appreciate the work of others.
I hope the new year will see more interest in spetroscopy from the AAVSO.
Hopkins Phoenix Observatory
Terrible conditions with bushfires and heavy smoke haze...
Managed to collect the Hb, Na and Ha series from the 10th.
The P-Cyg profile almost gone but new absroption features coming in.
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