Suspected Symbiotic Stars: campaign for Adrian Lucy

[Francois Teyssier]

A list of suspected symbiotic stars is published in AAVSO notice :https://www.aavso.org/aavso-alert-notice-650
A campaign on the request of Adrian Lucy and Jeniffer Solkolovski (Columbia University)
Faint targets, a nice goal for Alpy, LISA and other low resolution spectrograph.
What is expected is : late type continuum (giant M) and high ionisati on lines such as He II, [OIII], [Fe VII], Raman OVI ...
At least one of them is needed for identification of the target as a symbiotic star (See Belczinski & al., 2000)
The spectra will be added to ARAS database : http://www.astrosurf.com/aras/Aras_Data ... eStars.htm
Send spectra to lucy@astro.columbia.edu and francoismathieu.teyssier at bbox.fr
Good hunt!

François Teyssier

[Francois Teyssier]

Page created in the data base: http://www.astrosurf.com/aras/Aras_Data ... pected.htm

[Forrest Sims]

Greetings,

I saw François's request for spectrum on these potential Symbiotics.

I chose EN Sgr last night to see if I could get a spectrum. As you might have noticed all of these targets have a big fat (-) minus sign in front of the DEC. Makes me think they are made to order for Paul Lukas:) Add in the position of the Moon, the magnitudes and that many of these targets are setting in the west early in the evening reduces the candidates I can reach here from southern Arizona. I took 8 600sec images of EN Sgr with my LISA using HD214994 as a Reference star.

Here is a plate solved guider image of the field and the results displayed in PlotSpectra. Some preliminary analysis by François and Adrian Lucy point in the direction of this possibly being a Carbon Mira type star.

Cheers!
Woody

[Francois Teyssier]

Makes me think they are made to order for Paul Lukas:)

Or for Terry who added two spectra in the base: http://www.astrosurf.com/aras/Aras_Data ... pected.htm
Another spectrum of EN Sgr confirms Woody's observations: Balmer lines in emission, but no sign of high ionization lines (He II, [OIII], [Fe VII], [Fe X], [Ca V], Raman OVI)
The Balmer decrement is normal. The continuum evoques a C star, but flat.
A difficulty is that for some symbiotics, high ionisation lines appears only in UV. See for instance our spectra of NQ Gme, UV Aur, BD Cam ... Or are sporadic (remember that CH Cyg was a M giant standart until the early 60' when appeared for the fist time its symbiotic characteristics ([OIII])
and a spectrum of Gaia DR2 6345873798283774848 (no emission on the red continuum)
One interesting aspect of this campaign is that we have also to determine the spectral class of the targets
"what is that spectrum?" An excellent school

François

[Terry Bohlsen]

I've taken a spectrum of another candidate on the list. This one in Sgr.
GAIA DR 24048168377818693632. No emission lines are visible but lots of close absorption lines.
Cheers
Terry

[Francois Teyssier]

An excellent beginning, Woody and Terry

The summary of the campaign - current status: http://www.astrosurf.com/aras/Aras_Data ... tedLog.htm

In blue: targets observable from northern hemisphere (low but possible)

All the best,

François

[Francois Teyssier]

ASASSN-V J192916.53-2240403 obtained by Woody Sims with LISA

M3.5 continuum, H alpha and H beta (normal decrement)
A promising candidate

asassn-vj192916.53-2240403_20180921_153_Forrest Sims.png (41.7 KiB) Viewed 4209460 times

Blue and Black: MIII3 and M4III Pickles

Updated log:

suspected.PNG (66.02 KiB) Viewed 4209460 times

François

[Francisco Campos]

Hi,

after a long absence, I tried to take some spectra of these suspected symbiotic star. They are very faint and bad placed to my observatory and, after trying with two different stars and avoiding guidage problems with PHD2, only with GAIA DR2 4150446010182968192 I could obtain something decent. With the other star (GAIA DR2 4150099732733246112) the spectrum I could obtain was too faint, although there were no emission signals also).

This suspected doesn't show emission lines

_gaiadr24150446010182968192_20181004_783_FPC.png (10.43 KiB) Viewed 4209378 times

Grettings,
Fran

[Francois Teyssier]

Excellent result on a faint target, Fran!
The continuum evoques a M4 giant

Update of the journal:

suspected.PNG (64.1 KiB) Viewed 4209312 times

François

[Christophe Boussin]

Hello all,

During our mission to the Pic du Midi from 22 to 26 October 2018, our team (Christophe Boussin, Michel Verlinden, Jean-Paul Godard and Hubert Colpin) was able to obtain, thanks to the 60 cm telescope and an Alpy 600, a first spectrum of the suspected symbiotic star FASTT 1100 of magnitude 14 !!

The following spectrum was obtained on October 24, 2018 at 18 h 56 UT (JJ = 2458416.311) with a resolution of 585 and an acquisition time of 60 min (12 x 300 s).

FASTT1100 on October 24th (T60 Pic du Midi / Alpy 600)

_fastt1100_20181024_789_Christophe Boussin_4000_7800_T60.png (142.42 KiB) Viewed 4208949 times

FASTT1100 on October 24th (T60 Pic du Midi / Alpy 600)

The observation conditions were not optimal (full Moon, low height of the target above the horizon) but it's possible to recognize without ambiguity the hydrogen Halpha and Hbeta lines in emission while the Helium HeI lines at 5876 and 6678A remain very uncertain.
The other lines are mentioned for information only...

Clear skies,

Christophe BOUSSIN