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ASASSN-V J195442.95+172212.6 10.7V mag in Sge

PostPosted: Thu Aug 09, 2018 6:34 pm
by Peter Somogyi
If the speculation correct, confirmation and spectroscopy should be urgent:
http://www.cbat.eps.harvard.edu/unconf/ ... 22281.html

- Peter

Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

PostPosted: Thu Aug 09, 2018 9:14 pm
by Paolo Berardi
Hi Peter, the fresh spectrum from Italy (luckily clear sky here). Flux calibrated with mean V mag (10.73) during the observation.

Image

Hydrogen and helium emission lines.

Paolo

Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

PostPosted: Thu Aug 09, 2018 9:38 pm
by Peter Somogyi
Thank you Paolo for the spectrum! (especially because I cannot shoot this night...)
Looks like a kind of symbiotic outburst.

Robert Fidrich has this newly found variable star ("Vend S955") already on his observing plan for a longer time, here is his light curve:
Vend_S955__asassn_lc__420_50pct.png
Vend_S955__asassn_lc__420_50pct.png (53.12 KiB) Viewed 4014 times


A fresh Vmag is 10.85V (observer: Tamas Tordai) so it may have stopped.

- Peter
EDIT: this light curve is from ASAS-SN

Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

PostPosted: Fri Aug 10, 2018 6:43 am
by Francois Teyssier
This is fantastic! Congratulations Paolo !!!! :P
Peter: thank you for the alert and informations
Clearly a symbiotic with He II and perhaps [OIII] (He II is sufficient for symbiotic classification with Balmer lines in emission on a read giant continuum)
The amplitude of the variation before optical outburst is very low for a Mira
I open a page in the data base
Of course, coverage of the event is strongly recommended.
High resolution and Echelle spectra are expected.
Ranges : [OIII] 5007, NIII/CIII 4640 + He II, [Fe VII] 6087 and Raman OVI 6830

François

Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

PostPosted: Fri Aug 10, 2018 8:12 am
by Francois Teyssier
Clarification post by Robert Fidrich:
François

Some clarification.

I found this star in outburst during our "Vendégcsillag-kereső" (Gust Star Hunter) nova patrol programme. There was a sudden brightening in a few days - in contradiction of the original semiregular variable (SR) classification based on archives ASAS-SN photometry.

The light curve attached by Peter on the forum was not made by me, but the can be generated/downloaded through the ASAS-SN website:

https://asas-sn.osu.edu/light_curves/75f05b0b-18c4-418d-8218-93030b616a2d
https://asas-sn.osu.edu/light_curves/cdab0df3-ce2f-4a6a-9a4e-4ae1b32f1ca2

So this was originally classified as SR variable - not a Mira.

It's realy exciting to catch a new symbiotic variable in it's firts know outburst.

Thank you for your fast reactions!

Clear skies,

Robert

Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

PostPosted: Fri Aug 10, 2018 8:41 am
by Francois Teyssier
Page opened in the database:
http://www.astrosurf.com/aras/Aras_Data ... +17222.htm

François

Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

PostPosted: Fri Aug 10, 2018 8:48 pm
by Olivier GARDE
Weather is good and I'm now on this target with eShel spectrograph.

Image

Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

PostPosted: Sat Aug 11, 2018 1:05 am
by Christian Buil
A spectrum just taken of the object by using a Ritchey-Chretien 10-inch f/8 and UVEX2 spectrograph associated to an ASI183MM CMOS camera :

Image

Image

Infos up to 3500 A (note the UV jump).

Christian B

Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

PostPosted: Sat Aug 11, 2018 8:24 am
by Paolo Berardi
Great spectra!

Yesterday I observed h-alpha line with 2400 l/mm grating (suggested by U. Munari).

Image

Radial velocity:

Image

Paolo

Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

PostPosted: Sat Aug 11, 2018 8:56 am
by umberto sollecchia
Bonjour à tous, voici ma contribution en basse résolution. Umberto

tcpj19544251+1722281_20180810_878_Umberto Sollecchia.png
tcpj19544251+1722281_20180810_878_Umberto Sollecchia.png (31.54 KiB) Viewed 3762 times