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Re: New transcient, perhaps a nova

PostPosted: Sat Jul 01, 2017 8:17 pm
by Forrest Sims
Thank you Paulo, Umberto and François!

I just read the paper that François provided a link. And then thinking about Paulo's question on the possible FeII lines in our spectrum data. I found this additional paper that may be relevant.
https://arxiv.org/pdf/1208.0380.pdf

This is making my brain hurt but in a good way:)

Saluti!
Woody

Re: New transcient, perhaps a nova

PostPosted: Sun Jul 02, 2017 10:42 am
by Joan Guarro Flo
Bongiorno Paolo,

These days I'm away from home. Today I return to Piera and I can intertweet to make this star ...

But now I have difficulties with the IRAS17449 + 2320 of the 10 Mag. My observations of the Owl are really precarious. The ASASSN-17ib, with a magnitude of 11.43, can be beyond my possibilities.

A presto, Joan.

Re: New transcient, perhaps a nova

PostPosted: Sun Jul 02, 2017 2:26 pm
by Francois Teyssier
About Fe II (42) : good identification, Paolo.
Steve's comment:
The Fe II shows a weak P Cyg with a velocity compatible with marginally opaque. The He I is interesting but more the strength of the Na I D is neat. That there's emission there is also nice, it's chopped up by the interstellar component.

About William's classification. This is just taxonomic. The physics behind is contested (discrete ejecta follwed by a slower wind) notably by Steve.
Other papers of interest from Williams, showing spectroscopic development of a nimber of novae :

[1] The formation of novae spectra
R.E. Williams
A.J., Vol. 104, Number 2, 1992

[2] The evolution and classification of postoutburst novae spectra
R.E. Williams & al.
A.J., 376:721-737, 1991

[3] The Tololo nova survey : spectra of recent novae
R.E. Williams, M.M. Phillips, M. Hamuy
A.J. supp. ser., 90:297-316, 1994

and

[6] Origin of the `He/N' and `Fe II' Spectral Classes of Novae
Robert Williams
http://arxiv.org/ftp/arxiv/papers/1208/1208.0380.pdf, 2012

My page about novae (to be updated)

http://www.astronomie-amateur.fr/Projets%20Spectro4%20Novae.html

François

Re: New transcient, perhaps a nova

PostPosted: Sun Jul 02, 2017 7:53 pm
by Paolo Berardi
Hi all! Joan, yesterday I measured mag V 11.32. H-alpha is strong, also h-beta but the continuum and other lines are weak. I hope it's within your reach.

François, thanks a lot for your and Steve's valuable information. Yesterday I observe it with Lhires III and 600 l/mm grating.

Fe multiplet is more clear:

Image

Radial velocity of the three Fe II lines (P-Cygni):

Image

Radial velocity of H-beta P-Cygni profile:

Image


H-alpha region:

Image

Radial velocity of H-alpha P-Cygni profile:

Image

Paolo

PS: the profiles are calibrated in absolute flux by means of a rescaling to Umberto's fluxed spectrum

Re: New transcient, perhaps a nova

PostPosted: Sun Jul 02, 2017 7:59 pm
by umberto sollecchia
Bonsoir à tous, ma contribution avec un profil dans l'observation de la nuit 01/07/2017
Le profil est calibré en flux absolu avec la photométrie de Paul exécuté en même temps.
Umberto

Profilo nova Flux.png
Profilo nova Flux.png (6.12 KiB) Viewed 3608 times

Re: New transcient, perhaps a nova

PostPosted: Tue Jul 04, 2017 8:37 am
by umberto sollecchia
Bonjour à tous, placez le profil d'observation de la nuit de 03-07-2017.Umberto

Profilo nova.png
Profilo nova.png (6.5 KiB) Viewed 3584 times

Re: New transcient, perhaps a nova

PostPosted: Tue Jul 04, 2017 6:16 pm
by Forrest Sims
Hello everyone!

Nice work Umberto.

Here is my contribution from early on 4 July taken with the LISA. I have made some improvements to my focus that reduced the FWHM of the NeAr lines thanks to some help from François. So my resolution is much better than for the previous data I posted on this target. However I see a dip or belly in the continuum of my curve from about 4200Å to 5900Å that I cannot explain. I used the Reference star HD207673 and the MILES reference spectrum in ISIS to determine the response curve. The Hbeta line being so strong tends to suppress the detail that is really there when zoomed in on the other emission lines Does anyone have an idea as to why this continuum dip?

Thank you.

Woody

Re: New transcient, perhaps a nova

PostPosted: Tue Jul 04, 2017 9:42 pm
by umberto sollecchia
Merci Forrest, le problème du continuum, je pense qu'il est parce que le target n'a pas été placé exactement au centre de la fente, ou même la réponse instrumentale.
J'ai utilisé le miles hd179761 comme une étoile de référence.
Saluti-
Umberto

Re: New transcient, perhaps a nova

PostPosted: Wed Jul 05, 2017 10:23 am
by umberto sollecchia
Forrest Bonjour, il me semble que le profil de l'étoile HD207673 (ci-joint) que vous avez utilisé pour référence est un peu étrange. J'utiliser une autre étoile.

profilo hd 207673.png
profilo hd 207673.png (3.99 KiB) Viewed 3550 times


Salutations
Umberto

Re: New transcient, perhaps a nova

PostPosted: Wed Jul 05, 2017 2:30 pm
by umberto sollecchia
Bonjour, placé le profil d'observation de la nuit 07/04/2017. Il est calibré en flux absolu avec la photométrie par Paolo en même temps.Umberto

Profilo Nova Flux US.png
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