J/A+A/465/469 High spatial resolution observations of HM Sge (Sacuto+, 2007)
A compact dust shell in the symbiotic system HM Sge.
Sacuto S., Chesneau O., Vannier M., Cruzalebes P.
<Astron. Astrophys. 465, 469 (2007)>
=2007A&A...465..469S 2007A&A...465..469S
ADC_Keywords: Interferometry ; Stars, variable
Keywords: techniques: interferometric - techniques: high angular resolution -
stars: AGB and post-AGB - stars: binaries: symbiotic -
stars: circumstellar matter - stars: mass-loss
Abstract:
We present high spatial resolution observations of the mid-infrared
core of the dusty symbiotic system HM Sge obtained with the Very Large
Telescope Interferometer (VLTI) of ESO's Paranal Observatory and MIDI,
the MID-infrared Interferometric recombiner. MIDI combines the light
of two telescopes and provides spectrally resolved visibilities in the
N band atmospheric window. The observations of HM Sge were conducted
with the VLT Unit Telescopes (UTs) UT2, UT3 and UT4, providing
projected baselines in the range of 32-59 meters oriented from
PA=42deg to 105deg and the Auxiliary Telescopes (ATs) E0 and G0,
providing projected baselines in the range of 13.5-16 meters oriented
around PA=75deg. The UTs observations were made during the nights of
July 23-24th 2005, May 17th 2006 and June 11th 2006. The ATs
observations were made during the nights of May 27th 2006 and June
16th 2006. All the observations were made under good atmospheric
conditions (Mean[seeing]∼1.01") with the worst seeing (∼1.75") during
the night of July 23th 2005. The files includes all visibility and
differential phase data recorded from these observations as well as
all the characteristics concerning the observations. The log of the
observations is shown in Table 1 of the paper (table1.dat).
Description:
All the data products are stored in the FITS-based, optical
interferometry data exchange format (OI-FITS), described in Pauls et
al. (2005PASP..117.1255P 2005PASP..117.1255P). The OI Exchange Format is a standard for
exchanging calibrated data from optical (visible/infrared) stellar
interferometers. The standard is based on the Flexible Image Transport
System (FITS), and supports storage of the optical interferometric
observations including visibilities and differential phases. Several
routines to read and write this format in various languages can be
found in: Webpage http://www.mrao.cam.ac.uk/~jsy1001/exchange
Objects:
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RA (2000) DE Designation(s)
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19 41 57.1 +16 44 40 HM Sge = NOVA Sge 1975
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 55 16 Journal of the VLTI/MIDI observations of HM Sagittae
fig/* . 8 Spectrally-dispersed visibilities and differential
phases
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Star Star name
13- 22 A10 "YYYY-MM-DD" Obs.Date Observation date
24- 31 A8 --- Obs.Time Observation time (hh:mm:ss)
33- 36 F4.2 --- Phase ?=- Phase Mira
38- 41 F4.1 m Base ?=- Base
43- 45 I3 deg PA ?=- Position angle
47- 55 A9 --- FileName Corresponding fits file, in subdirectory fig
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Acknowledgements:
Stephane Sacuto, Stephane.Sacuto(at)obs-azur.fr
(End) Patricia Vannier [CDS] 12-Jan-2007