Request for spectrum asassn 20mg dec 48 south

Hamish Barker
Posts: 226
Joined: Thu Jun 20, 2019 12:11 am

Re: Request for spectrum asassn 20mg dec 48 south

Post by Hamish Barker »

Good one Terry. Indeed, juggling family priorities of making dinner, bedtime story for my son, and then getting scope aligned (invariably I bump the scope slipping a clutch, or pull too hard on the cover when unwrapping it, so have to reaquire alignment stars), I find it a bit of a race to get enough exposure of this object before it gets too low.

But good that you got some data, and it's similarly undramatic (the dropoffs at each end of mine are I think contaminating stars in the background sky pixel stripes. I found it quite hard to find any areas free of either zero order or first order contamination.

Cloudy here for a few days, but I will persist when it clears. Never know if something may pop up in the spectrum!
Hamish Barker
Posts: 226
Joined: Thu Jun 20, 2019 12:11 am

Re: Request for spectrum asassn 20mg dec 48 south

Post by Hamish Barker »

Krzysztof (director of ASAS-SN project) sent me a message that "Michigan State group says they see emission lines, but I did not see the spectrum."

Will be interesting to see if emission lines develop as they report, or what the object turns out to (probably) be.
Peter Velez
Posts: 146
Joined: Tue May 12, 2020 7:36 am

Re: Request for spectrum asassn 20mg dec 48 south

Post by Peter Velez »

Here is my spectrum from last week in all its ugliness.

I've added a synthetic F5V spectrum for comparison. Looks a reasonable match to me.

Pete
Attachments
2020tyr_20201014_389_Peter Velez.png
Hamish Barker
Posts: 226
Joined: Thu Jun 20, 2019 12:11 am

Re: Request for spectrum asassn 20mg dec 48 south

Post by Hamish Barker »

Great one peter. Not ugly! I think it is interesting that the F-G type spectral trend seems consistent with what I posted. Is that a little emission at H-alpha? Given the noise, H beta and gamma could well also be hidden in there.

Does anyone have any further thoughts on its likely identification?


I am very interested to overlay your spectrum along with Terry's and mine, in order to compare and try to . I can send you the fits file of my spectrum or you could send me yours to hamish dot barker at gmail dot com.


Terry if you are reading, could you please send yours also or we can send them to you for overlaying to compare?

Cheers,
Hamish
Terry Bohlsen
Posts: 191
Joined: Thu Sep 29, 2011 7:40 am

Re: Request for spectrum asassn 20mg dec 48 south

Post by Terry Bohlsen »

Hamish.
I sent you an email about the fit file.
Cheers
Terry
Terry Bohlsen
Armidale NSW
Australia
Hamish Barker
Posts: 226
Joined: Thu Jun 20, 2019 12:11 am

Re: Request for spectrum asassn 20mg dec 48 south

Post by Hamish Barker »

light_curve_a043ee84-556b-4e0e-9207-78b16a61763e.png
Brightness is declining. Raining here today so no chance of an observation.

Latest asas-sn light curve included above. If it is a nova then I guess emission lines should get more obvious.
Hamish Barker
Posts: 226
Joined: Thu Jun 20, 2019 12:11 am

Re: Request for spectrum asassn 20mg dec 48 south

Post by Hamish Barker »

Someone finally put a 2m telescope onto the job and posted classification of CV on23 October.

https://wis-tns.weizmann.ac.il/object/2020tyr

Will be interesting if we can still get observations as it dims to see if emission lines get more prominent.
Hamish Barker
Posts: 226
Joined: Thu Jun 20, 2019 12:11 am

Re: Request for spectrum asassn 20mg dec 48 south

Post by Hamish Barker »

I combined Terry and Peter's spectra (note observations were different by a day) to reduce the noise a bit and overlaid the ESO spectrum from 23 October and my crappy SA100 .

I prepared an overall, and zooms on Halpha, beta, gamma and (maybe) sodium D regions.

anyone with CV expertise? Are they normally hotter than the apparent continuum slope seems to indicate in Terry and Peter's observations of around 6000K?

Cheers,
Hamish
Attachments
asas-sn-20mg-sodiumregion-5700-6100.png
asas-sn-20mg-H-gamma-region-4200-4500.png
asas-sn-20mg-H-Beta-region-4700-5100.png
asas-sn-20mg-Halpharegion-6400-6700.png
asas-sn-20mg-combined-3500-8000.png
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