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

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

Postby Francois Teyssier » Sat Aug 11, 2018 9:16 am

Page updtaed with Christian and last Paolo spectra
http://www.astrosurf.com/aras/Aras_Data ... +17222.htm
François

Daily coverage should be must
The lightcurve is very unusual for a classicla symbiotic outburst
Last edited by Francois Teyssier on Sat Aug 11, 2018 1:21 pm, edited 1 time in total.
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Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

Postby Olivier GARDE » Sat Aug 11, 2018 10:54 am

Spectrum taken last night with eShel spectrograph R=11000. Not very easy and poor SNR in the blue...

The full graph
Image

And others particular lines

Image
Image
Image
Image

The Balmer's lines
Image
LHIRES III #5, LISA, e-Shel, C14, RC400 Astrosib, AP1600
http://o.garde.free.fr/astro/Spectro1/Bienvenue.html
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Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

Postby Francois Teyssier » Sat Aug 11, 2018 1:20 pm

The ATel, written by Ulisse Munari

HBHa 1704-05: a bright and newly discovered symbiotic star,
currently undergoing an "hot-type" outburst

ATel #11937; U. Munari (INAF Padova), S. Dallaporta, P. Valisa
(ANS Collaboration), P. Ochner (Univ. Padova),
R. Fidrich (HAA/VSS), P. Berardi, O. Garde,
C. Buil (ARAS Group)
on 11 Aug 2018; 11:20 UT
Credential Certification: U. Munari (ulisse.munari@oapd.inaf.it)

Subjects: Cataclysmic Variable, Nova, Variables

HBHa 1704-05 was first noted by Kohoutek and Wehmeyer in their catalog of emission line stars (1999, A&AS, 134, 255), as a source with a strong continuum (thus not a PN) and overexposed Halpha emission. It seems not much else is available in literature. The star is coincident with 2MASS J19544295+1722125 (=ASASSN-V J195442.95+172212.6) catalogued by VSX (Otero 2018) as an SR variable with a periodicity around 418 days, and a range of variability 13.2-12.4 in V band.

On patrol sky observations obtained with a Canon EOS 1000D plus 180mm focus lens, one of us (R.F.) recently noted a rapid increase in brightness amounting to (preliminary calibrated) V~12.0 on July 31.945 UT, V~11.7 on Aug 3.989, and V~10.7 mag on Aug 8.938. The trend was confirmed by inspection of the on-line ASASSN database. An exploratory spectrum was soon obtained on UT Aug 9.839 by one of us (P.B.) with a 23cm+Lhires III telescope, showing a rich emission line spectrum that prompted to collect deeper observations.

On UT Aug 10.837 we have observed HBHa 1704-05 with ANS Collaboration telescope ID 310 obtaining B=11.459, V=10.926, R=10.101, and I=9.199. Comparing with APASS mean values for quiescence, B=13.798 and V=12.637, the object is now 2.3 mag brighter in B and far bluer in color (from B-V=+1.16 to +0.53).

A deep 3200-7900 Ang spectrum of HBHa 1704-05 was obtained on UT Aug 10.855 at 2.31 Ang/pix dispersion with the Asiago 1.22m telescope, while the Varese 84cm provided a high resolution Echelle spectrum on UT Aug 10.882. The spectrum of HBHa 1704-05 is characterized by TiO absorption bands from an M giant in the red, progressively veiled by nebular emission toward the blue, with a prominent Balmer continuum in emission. A lot of strong emission lines are present, with HeII 4686 of the same intensity of Hbeta, and [NeV] 3426 suggesting a photo-ionization temperature in excess of 100,000 K. A prominent NIII 4640 complex is accompanied by OIV 3411 and OIII 3313, 3429, and 3444, indicating that pumping under Bowen fluorescence, initiated by HeII Ly-alpha photons at 303.8 Ang, is active. Forbidden lines characterized by a low critical density are absent, and also absent is the Raman scattered OVI pair at 6825, 7088 Ang. On the Echelle spectrum, the emission lines appear remarkably sharp and symmetric, without P-Cyg absorptions or other signatures of mass loss being visible, and with broad wings for the Balmer lines that suggest a large electron pressure. Bowen-pumped OI 8446 is present as are low-excitation emission from FeII multiplet 42, NaI D1,D2 and infrared CaII triplet.

We therefore conclude that HBHa 1704-05 is a previously unknown symbiotic binary, currently undergoing an "hot-type" outburst, with the wind of the cool giant being increasingly ionized by a hot companion rising in Teff. Its Gaia parallax suggests a distance of 3.6 kpc (albeit with a large error), and Schlafly et al. (2011, ApJ 737, 103) extinction maps indicate a reddening E(B-V)=0.28. The latter is confirmed by the low equivalent width for DIB 6614 and KI 7699. Combining APASS mean BVgri photometry in quiescence with 2MASS JHK data, a spectral type around M3III can be inferred for the M giant, in agreement with M(V)=-1.0 in quiescence from Gaia parallax.

The large brightness attended by the ongoing outburst of HBHa 1704-05 and its favorable position on the sky will undoubtedly support a large, all-out observing effort, we plan to join.
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Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

Postby Christophe Boussin » Sun Aug 12, 2018 12:52 am

Bonjour à tous,

Merci pour ces informations François !
Voici ma contribution au suivi de TCPJ19544251+17222 obtenu ce 11 Août à 21 h 57 TU avec une résolution de 502 (JJ = 2458342.4374) et une durée d'acquisition de 40 min (8 x 300 s).

_tcpj19544251+17222_20180811_915_Christophe Boussin_3700_7570.png
TCPJ19544251+17222 le 11 Août 2018
_tcpj19544251+17222_20180811_915_Christophe Boussin_3700_7570.png (100.01 KiB) Viewed 598 times


Spectroscopicalement,

Christophe BOUSSIN
CBO (Newton 200 F/5 / Alpy600 / Atik 314L+ / Atik Titan) @ ARAS database
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Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

Postby Francois Teyssier » Sun Aug 12, 2018 5:59 am

C'est trés bon, Christophe.
Observations à poursuivre
François
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Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

Postby Olivier GARDE » Sun Aug 12, 2018 12:08 pm

Last observation and comparison in 24h interval

The full spectrum
Image

Balmer's lines
Image

He I and others lines
Image

The most signicative evolution is in the blue wing of He II 4686
Image
LHIRES III #5, LISA, e-Shel, C14, RC400 Astrosib, AP1600
http://o.garde.free.fr/astro/Spectro1/Bienvenue.html
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Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

Postby Peter Somogyi » Sun Aug 12, 2018 12:17 pm

Fresh results from yesterday with 300/1200 Newton + 2.67x APM Barlow + LHires 2400/mm, 35 micron slit, ATIK 428 EXm (2/3" chip size), provides R~9400 local resolution in the blue and R~1300 at 6000A.
The [FeVII 6087] seems to be nonexistent, a tiny feature at 6083A detectable but clearly away:
FeVII_6087.gif
FeVII_6087.gif (25.47 KiB) Viewed 576 times

The [OIII 5007] is also nonexistent:
OIII_HeI_FeII.gif

The best region for an LHires with the 2400mm grating looks to be NIII/CIII:
NIIICIIIHeII.gif
NIIICIIIHeII.gif (32.15 KiB) Viewed 576 times

Sent spectra to database, including also a Hb + He I 4622 region that seem to already match well with Olivier's eShel spectrum above.
- Peter
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Re: ASASSN-V J195442.95+172212.6 10.7V mag in Sge

Postby Paolo Berardi » Sun Aug 12, 2018 2:55 pm

Hi Peter, all,

yesterday I also observed the symbiotic with Lhires III and 600 l/mm grating.

Image

The detail around He I 5016 (unresolved pair with Fe II 5018) seems a little different than your. The signal is poor but feel like there is something near the oxygen line wavelength. To be explored...

Image

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

Postby Christian Buil » Sun Aug 12, 2018 3:58 pm

Fine Paolo and all !

The blue/UV version of the symbiotic taken the 11.97/08/2018 (I have pushed down to 3400 A - I detect only noise near these wavelength) :

Image

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

Postby Francois Teyssier » Sun Aug 12, 2018 4:34 pm

Congratulations to all
I've also received spectra from Keith Graham and Christophe Boussin
The base will be updated tomorrow (no access to ftp today)

We are waiting for an AAVSO Alert for photometry ...

AAVSO chart : https://www.aavso.org/apps/vsp/chart/X23149BG.png


Olivier: classical behavior of He II line during a classical symbiotic outburst
Three explanations have been developped to explain the broad wings. There's no consensus.
1. wind from the hot component
2. electron scattering
3. accretion disk

François
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