J/A+A/631/A108 Disks around post-AGB binaries fit results (Kluska+, 2019)
VLTI/PIONIER survey of disks around post-AGB binaries.
Dust sublimation physics rules.
Kluska J., Van Winckel H., Hillen M., Berger J.-P., Kamath D.,
Le Bouquin J.-B., Min M.
<Astron. Astrophys. 631, A108 (2019)>
=2019A&A...631A.108K 2019A&A...631A.108K (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Infrared sources ; Interferometry
Keywords: stars: AGB and post-AGB - techniques: high angular resolution -
techniques: interferometric - binaries: general -
circumstellar matter - protoplanetary disks
Abstract:
Post-asymptotic giant branch (pAGB) binaries are surrounded by
circumbinary disks of gas and dust that are similar to protoplanetary
disks found around young stars.
We aim to understand the structure of these disks and identify the
physical phenomena at play in their very inner regions. We want to
understand the disk-binary interaction and to further investigate the
comparison with protoplanetary disks.
We conducted an interferometric snapshot survey of 23 post-AGB
binaries in the near-infrared (H-band) using VLTI/PIONIER. We fit the
multi-wavelength visibilities and closure phases with purely
geometrical models with an increasing complexity (including two
point-sources, an azimuthally modulated ring, and an over-resolved
flux) in order to retrieve the sizes, temperatures, and flux ratios of
the different components.
All sources are resolved and the different components contributing to
the H-band flux are dissected. The environment of these targets is
very complex: 13/23 targets need models with thirteen or more
parameters to fit the data. We find that the inner disk rims follow
and extend the size-luminosity relation established for disks around
young stars with an offset toward larger sizes. The measured
temperature of the near-infrared circumstellar emission of post-AGB
binaries is lower (Tsub∼1200K) than for young stars, which is probably
due to a different dust mineralogy and/or gas density in the dust
sublimation region.
The dusty inner rims of the circumbinary disks around post-AGB
binaries are ruled by dust sublimation physics. Additionally a
significant amount of the circumstellar $H$-band flux is over-resolved
(more than 10% of the non-stellar flux is over-resolved in 14
targets). This hints that a source of unknown origin, either a disk
structure or outflow. The amount of over-resolved flux is larger than
around young stars. Due to the complexity of these targets,
interferometric imaging is a necessary tool to reveal the interacting
inner regions in a model-independent way.
Description:
Best-fit parameters of the geometric models fitted to the
interferometric dataset on 23 post-AGB binaries. It describes the star
(sometimes binary if detected) and its circumbinary environment. We
have fitted models with increasing complexity and only the most likely
model is present in the table.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fitparam.dat 345 23 Best-fit parameters of the most likely model
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Byte-by-byte Description of file: fitparam.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- ID Target index (ID)
4- 17 A14 --- Target Name of the target (Target)
19- 22 I4 --- Ndata Number of data points (ndata)
24- 26 A3 --- Model name of the most likely model (model)
28- 33 F6.1 --- BIC Bayesian Information Criterion value (BIC)
35- 37 F3.1 --- chi2red Reduced chi2 (chi2red)
39- 42 F4.1 --- fprim0 ?=- primary-to-total flux ratio at 1.65um
(fprim0)
44- 46 F3.1 --- E_fprim0 ?=- one sigma upper limit of fprim0 (sufprim0)
49- 52 F4.1 --- e_fprim0 ?=- one sigma lower limit of fprim0 (slfprim0)
54- 57 F4.1 --- fsec0 ?=- secondary-to-total flux ratio at 1.65um
(fsec0)
59- 61 F3.1 --- E_fsec0 ?=- one sigma upper limit of fsec0 (sufsec0)
64- 66 F3.1 --- e_fsec0 ?=- one sigma lower limit of fsec0 (slfsec0)
68- 71 F4.1 --- fbg0 ?=- background-to-total flux ratio at 1.65um
(fbg0)
73- 75 F3.1 --- E_fbg0 ?=- one sigma upper limit of fbg0 (sufbg0)
78- 80 F3.1 --- e_fbg0 ?=- one sigma lower limit of fbg0 (slfbg0)
82- 85 F4.1 --- dsec ?=- spectral index of the secondary (dsec)
87- 89 F3.1 --- E_dsec ?=- one sigma upper limit of dsec (sudsec)
92- 94 F3.1 --- e_dsec ?=- one sigma lower limit of dsec (sldsec)
96- 99 F4.1 --- dback ?=- spectral index of the background (dback)
101-103 F3.1 --- E_dback ?=- one sigma upper limit of dback (sudback)
106-108 F3.1 --- e_dback ?=- one sigma lower limit of dback (sldback)
110-113 I4 K Tring ?=- ring temperature (Tring)
115-118 I4 K E_Tring ?=- one sigma upper limit of Tring (suTring)
121-124 I4 K e_Tring ?=- one sigma lower limit of Tring (slTring)
126-129 F4.1 mas rD ?=- ring diameter (rD)
131-133 F3.1 mas E_rD ?=- one sigma upper limit of rD (surD)
136-138 F3.1 mas e_rD ?=- one sigma lower limit of rD (slrD)
140-143 F4.2 --- rW ?=- ring width in units of ring diameter (rW)
145-148 F4.2 --- E_rW ?=- one sigma upper limit of rW (surW)
151-154 F4.2 --- e_rW ?=- one sigma lower limit of rW (slrW)
156-161 F6.3 deg inc ?=- ring inclination (inc)
163-167 F5.3 deg E_inc ?=- one sigma upper limit of inc (suinc)
170-175 F6.3 deg e_inc ?=- one sigma lower limit of inc (slinc)
177-179 I3 deg PA ?=- ring Position Angle (PA)
181-183 I3 deg E_PA ?=- one sigma upper limit of PA (suPA)
186-187 I2 deg e_PA ?=- one sigma lower limit of PA (slPA)
189-193 F5.2 --- c1 ?=- c1 coefficient of azimuthal ring
modulation (c1)
195-198 F4.2 --- E_c1 ?=- one sigma upper limit of c1 (suc1)
201-204 F4.2 --- e_c1 ?=- one sigma lower limit of c1 (slc1)
206-210 F5.2 --- s1 ?=- s1 coefficient of azimuthal ring
modulation (s1)
212-215 F4.2 --- E_s1 ?=- one sigma upper limit of s1 (sus1)
218-221 F4.2 --- e_s1 ?=- one sigma lower limit of s1 (sls1)
223-227 F5.2 --- c2 ?=- c2 coefficient of azimuthal ring
modulation (c2)
229-232 F4.2 --- E_c2 ?=- one sigma upper limit of c2 (suc2)
235-238 F4.2 --- e_c2 ?=- one sigma lower limit of c2 (slc2)
240-244 F5.2 --- s2 ?=- s2 coefficient of azimuthal ring
modulation (s2)
246-249 F4.2 --- E_s2 ?=- one sigma upper limit of s2 (sus2)
252-255 F4.2 --- e_s2 ?=- one sigma lower limit of s2 (sls2)
257-262 F6.2 mas offsetx ?=- RA offset of the primary w.r.t. the
ring centre (offsetx)
264-268 F5.2 mas E_offsetx ?=- one sigma upper limit of offsetx
(suoffsetx)
271-275 F5.2 mas e_offsetx ?=- one sigma lower limit of offsetx
(sloffsetx)
277-281 F5.2 mas offsety ?=- DEC offset of the primary w.r.t. the
ring centre (offsety)
283-287 F5.2 mas E_offsety ?=- one sigma upper limit of offsety
(suoffsety)
290-294 F5.2 mas e_offsety ?=- one sigma lower limit of offsety
(sloffsety)
296-300 F5.3 --- rM ?=- mass ratio between the primary and the
secondary (rM)
302-306 F5.3 --- E_rM ?=- one sigma upper limit of rM (surM)
309-313 F5.3 --- e_rM ?=- one sigma lower limit of rM (slrM)
315-318 F4.2 mas primD ?=- diameter of the primary (primD)
320-323 F4.2 mas E_primD ?=- one sigma upper limit of primD (suprimD)
326-329 F4.2 mas e_primD ?=- one sigma lower limit of primD (slprimD)
331-334 F4.2 mas secD ?=- diameter of the secondary (secD)
336-339 F4.2 mas E_secD ?=- one sigma upper limit of secD (susecD)
342-345 F4.2 mas e_secD ?=- one sigma lower limit of secD (slsecD)
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Acknowledgements:
Jacques Kluska, jacques.kluska(at)kuleuven.be
(End) Jacques Kluska [Kuleuven Univ.], Patricia Vannier [CDS] 24-Sep-2019