J/A+A/559/A111 89 Her interferometric study (Hillen+, 2013)
An interferometric study of the post-AGB binary 89 Herculis.
I. Spatially resolving the continuum circumstellar environment at optical and
near-IR wavelengths with the VLTI, NPOI, IOTA, PTI and the CHARA Array.
Hillen M., Verhoelst T., Van Winckel H., Chesneau O., Hummel C.A.,
Monnier J.D., Farrington C., Tycner C., Mourard D., ten Brummelaar T.,
Banerjee D.P.K., Zavala R.T.
<Astron. Astrophys. 559, A111 (2013)>
=2013A&A...559A.111H 2013A&A...559A.111H
ADC_Keywords: Stars, double and multiple ; Stars, late-type ; Interferometry
Keywords: stars: AGB and post-AGB - circumstellar matter - binaries: general -
techniques: interferometric - scattering - ISM: jets and outflows
Abstract:
Binary post-asymptotic giant branch (post-AGB) stars are interesting
laboratories to study both the evolution of binaries as well as the
structure of circumstellar disks.
A multiwavelength high angular resolution study of the prototypical
object 89 Herculis is performed with the aim of identifying and
locating the different emission components seen in the spectral energy
distribution.
A large interferometric data set, collected over the past decade and
covering optical and near-infrared wavelengths, is analyzed in
combination with the spectral energy distribution and flux-calibrated
optical spectra. In this first paper only simple geometric models are
applied to fit the interferometric data. Combining the interferometric
constraints with the photometry and the optical spectra, we re-assess
the energy budget of the post-AGB star and its circumstellar
environment.
Description:
89 Herculis was observed with the AMBER instrument on the VLTI using
the Auxiliary Telescopes (ATs) in 2007, 2008, and 2012, all in the
low-spectral-resolution (R=30) mode covering the H and K bands with
detector integration times (DITs) of 25 and 50ms and without the use
of the fringe tracker FINITO.
Both the CLASSIC and CLIMB beam combiners on the Georgia State
University CHARA Array interferometer were used to conduct
observations in the H and K bands.In May 2012 observations were
performed with the sensitive two-beam CLASSIC beam combiner in both H
and K band. Three-beam CLIMB observations, in H and K band, were also
obtained during three nights in July 2012.
We retrieved and calibrated observations from the PTI archive.
89 Her was observed during 30 nights between 1999 and 2003, equally
spread over the H and K bands.
Eight and 15 observations of 89 Her were obtained at the IOTA
interferometer on 2003 June 15 and 16, respectively.
Observations of 89 Her were carried out in October 2011 with the
NPOI.
Two observations were performed in June and August 2011 with the
Visible spEctroGraph And Polarimeter (VEGA instrument) integrated
within the CHARA Array.
Objects:
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RA (2000) DE Designation(s)
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17 55 25.19 +26 03 00.0 89 Her = V* V441 Her
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 101 14 List of OI-FITS files
fits/* . 14 Individual OI-FITS files
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 40 A40 --- FileName Name of the OI-FITS file in subdirectory fits
43- 65 A23 --- Dates Observation date(s)
67-101 A35 --- Inst Instrument (1)
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Note (1): The instruments are:
CHARA = Center for High Angular Resolution Astronomy array
VLTI = Very Large Telescope Interferometer (ESO)
NPOI = Navy Precision Optical Interferometer
PTI = Palomar Testbed Interferometer
NPOI = Infrared Optical Telescope Array
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Acknowledgements:
Michel Hillen, michel.hillen(at)ster.kuleuven.be
(End) Patricia Vannier [CDS] 29-Aug-2013