J/A+A/591/A108 HD61005 SPHERE H and Ks images (Olofsson+, 2016)
Azimuthal asymmetries in the debris disk around HD61005.
A massive collision of planetesimals?
Olofsson J., Samland M., Avenhaus H., Caceres C., Henning T., Moor A.,
Milli J., Canovas H., Quanz S. P., Schreiber M. R., Augereau J.-C.,
Bayo A., Bazzon A., Beuzit J.-L., Boccaletti A., Buenzli E., Casassus S.,
Chauvin G., Dominik C., Desidera S., Feldt M., Gratton R., Janson M.,
Lagrange A.-M., Langlois M., Lannier J., Maire A.-L., Mesa D., Pinte C.,
Rouan D., Salter G., Thalmann C., Vigan A.
<Astron. Astrophys. 591, A108 (2016)>
=2016A&A...591A.108O 2016A&A...591A.108O (SIMBAD/NED BibCode)
ADC_Keywords: YSOs ; Morphology ; Polarization
Keywords: circumstellar matter - zodiacal dust -
techniques: high angular resolution
Abstract:
Debris disks offer valuable insights into the latest stages of
circumstellar disk evolution, and can possibly help us to trace the
outcomes of planetary formation processes. In the age range 10 to
100Myr, most of the gas is expected to have been removed from the
system, giant planets (if any) must have already been formed, and the
formation of terrestrial planets may be on-going. Pluto-sized
planetesimals, and their debris released in a collisional cascade, are
under their mutual gravitational influence, which may result into
non-axisymmetric structures in the debris disk.
Here we present new VLT/SPHERE and ALMA observations of the debris
disk around the 40Myr-old solar-type star HD61005. We resolve the
disk at unprecedented resolution both in the near-infrared (in
scattered and polarized light) and at millimeter wavelengths. We
perform a detailed modeling of these observations, including the
spectral energy distribution.
Thanks to the new observations, we propose a solution for both the
radial and azimuthal distribution of the dust grains in the debris
disk. We find that the disk has a moderate eccentricity and that the
dust density is two times larger at the pericenter compared to the
apocenter. With no giant planets detected in our observations, we
investigate alternative explanations besides planet-disk interactions
to interpret the inferred disk morphology. We postulate that the
morphology of the disk could be the consequence of a massive collision
between 1000km-sized bodies at 61 au. If this interpretation holds,
it would put stringent constraints on the formation of massive
planetesimals at large distances from the star.
Description:
The fits files contains the reduced ADI and DPI SPHERE observations
used to produce Fig. 1 of the paper. Besides the primary card, the
files consists of 6 additional ImageHDU. The first and second one
contain the SPHERE IRDIS ADI H band observations and the noise map.
The third and fourth contain the SPHERE IRDIS ADI Ks band observations
and the corresponding noise map. Finally, the fifth and sixth ImageHDU
contain the SPHERE IRDIS DPI H band data as well as the noise map.
Each ADI image has 1024x1024 pixels, while the DPI images have
1800x1800 pixels.
The header of the primary card contains the pixel sizes for each
datasets and the wavelengths of the H and K band observations.
Objects:
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RA (2000) DE Designation(s)
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07 35 47.46 -32 12 14.0 HD 61005 = HIP 36948
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 82 6 List of images in the fits file
sphere.fits 2880 29659 Fits image
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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)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 27 F8.6 arcsec/pix scale Scale of the image
29- 32 I4 --- Nx Number of pixels along X-axis
34- 37 I4 --- Ny Number of pixels along Y-axis
39- 42 F4.2 um lambda Wavelength for observed band
44- 48 I5 Kibyte size Size of FITS file
50 I1 --- HDU [1/6] Image HDU number in the fits file
52- 70 A19 --- FileName Name of FITS file
72- 82 A11 --- Title Title of the image
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Acknowledgements:
Johan Olofsson, johan.olofsson(at)uv.cl
(End) Patricia Vannier [CDS] 09-May-2016