J/A+A/595/A31 SAM detection limits of 8 debris disks (Gauchet+, 2016)
Sparse aperture masking at the VLT.
II. Detection limits for the eight debris disks stars β Pic, AU Mic,
49 Cet, η Tel, Fomalhaut, g Lup, HD181327 and HR8799.
Gauchet L., Lacour S., Lagrange A.-M., Ehrenreich D., Bonnefoy M.,
Girard J. H., Boccaletti A.
<Astron. Astrophys. 595, A31 (2016)>
=2016A&A...595A..31G 2016A&A...595A..31G (SIMBAD/NED BibCode)
ADC_Keywords: Stars, early-type ; Interferometry
Keywords: instrumentation: high angular resolution - planetary systems -
planets and satellites: formation
Abstract:
The formation of planetary systems is a common, yet complex mechanism.
Numerous stars have been identified to possess a debris disk, a
proto-planetary disk or a planetary system. The understanding of such
formation process requires the study of debris disks. These targets
are substantial and particularly suitable for optical and infrared
observations. Sparse aperture masking (SAM) is a high angular
resolution technique strongly contributing to probing the region from
30 to 200 mas around the stars. This area is usually unreachable with
classical imaging, and the technique also remains highly competitive
compared to vortex coronagraphy. We aim to study debris disks with
aperture masking to probe the close environment of the stars. Our goal
is either to find low-mass companions, or to set detection limits.
We observed eight stars presenting debris disks (β Pictoris,
AU Microscopii, 49 Ceti, η Telescopii, Fomalhaut, g Lupi,
HD 181327, and HR 8799) with SAM technique on the NaCo instrument at
the Very Large Telescope (VLT).
No close companions were detected using closure phase information
under 0.5" of separation from the parent stars. We obtained
magnitude detection limits that we converted to Jupiter masses
detection limits using theoretical isochrones from evolutionary
models.
We derived upper mass limits on the presence of companions in the area
of a few times the telescope's diffraction limits around each target
star.
Description:
VLT/NaCo Sparse Aperture Masking data for 8 debris disks in Lprime
spectral band (λ=3.80um, Δλ=0.62um). The
stars hosting debris disks observed are: β Pictoris,
AU Microscopii, 49 Ceti, η Telescopii, Fomalhaut, g Lupi, HD181327
and HR8799 (with respective calibrator: HR2049, HD197339, HD10100,
HD181517, del PsA, HD139960, HD180987, HD218234). No companion were
found in the observational data. For each star, we have processed a
5σ detection limit map of the neighbourhood of the star. The
primary array of each fits file contains a 237x237 pixel image
representing a 900x900 mas portion of the sky plane (i.e. 3mas/pixel).
The center of the array correspond to the location of the main star.
Detection limit values are stated in relative magnitude compared to
that of the main star.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 106 8 List of FITS images
fits/* . 8 Detection limits 2D maps expressed in relative
magnitude compared to that of the main star
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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- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
11- 19 F9.5 deg DEdeg Declination of center (J2000)
21- 23 I3 --- Nx Number of pixels along X-axis
25- 27 I3 --- Ny Number of pixels along Y-axis
29- 38 A10 "date" Obs.Date Observation date
40- 45 I6 byte Size Size of the FITS file
47- 58 A12 --- Filename Name of the FITS file in subdirectory fits
60-106 A47 --- Title Title of the file
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Acknowledgements:
Lucien Gauchet, lucien.gauchet(at)obspm.fr
References:
Lacour et al., Paper I 2011A&A...532A..72L 2011A&A...532A..72L
Sparse aperture masking at the VLT. I. Faint companion detection limits for
the two debris disk stars HD92945 and HD141569.
(End) Lucien Gauchet [LESIA - Obs. Paris], Patricia Vannier [CDS] 07-Jun-2016