J/MNRAS/383/845 Spectroscopy of AE Circinus (Mennickent+, 2008)
The remarkable properties of the symbiotic star AE Circinus.
Mennickent R., Greiner J., Arenas J., Tovmassian G., Mason E., Tappert C.,
Papadaki C.
<Mon. Not. R. Astron. Soc., 383, 845-856 (2008)>
=2008MNRAS.383..845M 2008MNRAS.383..845M
ADC_Keywords: Binaries, cataclysmic ; Spectroscopy
Keywords: binaries: general - stars: individual: AE Cir -
novae, cataclysmic variables
Abstract:
We present new optical spectroscopy and photometry, Two-Micron All-Sky
Survey (2MASS) infrared observations and 24yr of combined American
Association of Variable Star Observers (AAVSO) and Association
Francaise des Observateurs d'Etoiles Variables (AFOEV) photometry of
the symbiotic star candidate AE Cir. The long-term light curve is
characterized by outbursts lasting several years and having a slow
decline of ∼2x10-4mag/d. The whole range of variability of the star
in the V band is about 4mag. The periodogram of the photometric data
reveals strong signals at ∼342 and 171d. The presence of the emission
feature at λ6830Å at minimum and the detection of absorption
lines of a ∼K5 type star confirm the symbiotic classification and
suggest that AE Cir is a new member of the small group of s-type
yellow symbiotic stars. We estimate a distance of 9.4kpc. Our spectrum
taken at the high state shows a much flatter spectral energy
distribution, the disappearance of the λ6830Å emission
feature and the weakness of the HeII 4686 emission relative to the
Balmer emission lines. Our observations indicate the presence of
emission-line flickering in time-scales of minutes in 2001. The
peculiar character of AE Cir is revealed in the visibility of the
secondary star at the high and low state, the light curve resembling a
dwarf nova superoutburst and the relatively short low states. The data
are hard to reconciliate with standard models for symbiotic star
outbursts.
Description:
We present photometric time series obtained at La Silla and Cerro
Tololo Inter American Observatory (CTIO) during several seasons.
AE Cir was observed with the Dutch 0.9-m telescope at La Silla ESO
observatory in the night of 2001 April 5/6 in the V band.
We also observed AE Cir with the CTIO 1.3-m telescope operated under
the Small and Moderate Aperture Research Telescope System (SMARTS)
consortium in the seasons 2004 and 2005. Observations were made in
pairs of two exposures in B and R each.
We also present medium-resolution spectra of AE Cir obtained in 2000
May 29 and 30 with the 1.54-m Danish telescope at La Silla European
Southern Observatory (ESO), high-resolution spectra obtained at the
Paranal Observatory with the ESO-VLT-UT2 telescope during 2001 March
16, and a medium-resolution spectrum obtained at the CTIO with the 4-m
Blanco telescope during 2007 May 04.
Objects:
-----------------------------------------------------
RA (2000) DE Designation(s)
-----------------------------------------------------
14 44 51.3 -69 23 35 AE Circinus = V* AE Cir
-----------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 84 81 The emission lines observed in the spectra of AE Cir
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Ion Ion designation (or Unknown)
9- 16 F8.3 0.1nm lambda ?=- Laboratory wavelength
18- 25 F8.3 0.1nm lambdaO ?=- Observed wavelength
26- 30 F5.2 0.1nm EW2007 ?=- Equivalent width measured in 2007 spectra
31 A1 --- n_EW2007 [*] Merged equivalent width (1)
33- 37 F5.2 0.1nm EW2001 ?=- Equivalent width measured in 2001 spectra
38 A1 --- n_EW2001 [*] Merged equivalent width (1)
40- 43 F4.1 0.1nm EW2000 ?=- Equivalent width measured in 2000 spectra
44 A1 --- n_EW2000 [*] Merged equivalent width (1)
46- 48 I3 km/s GFWHM ?=- Full width at half maximum (2)
50- 53 I4 km/s RV ?=- Radial velocity at the line centre with
respect to the LSR (2)
55- 58 F4.1 eV Xion ?=- Ionization potential (2)
60- 63 F4.1 --- I/Ic ?=- Maximum line intensity normalized to the
continuum (2)
65- 67 A3 --- Flag [ab? nr] Flag on the line (3)
69- 84 A16 --- Note Note
--------------------------------------------------------------------------------
Note (1): The asterisk (*) indicates that the equivalent width is the total
width of the three Na D1 + Na D2 lines
Note (2): All parameters refer to 2001 spectra.
Note (3): Flag as follows:
nr = line not resolved
a = asymmetrical line
b = blended line
? = uncertain
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 26-Jan-2009