J/A+A/564/A51 3mm maps of 4 transition disks (Pinilla+, 2014)
Millimetre spectral indices of transition disks and their relation with the
cavity radius.
Pinilla P., Benisty M., Birnstiel T., Ricci L., Isella A., Natta A.,
Dullemond C.P., Quiroga-Nunez L.H., Henning T., Testi L.
<Astron. Astrophys. 564, A51 (2014)>
=2014A&A...564A..51P 2014A&A...564A..51P
ADC_Keywords: Stars, pre-main sequence ; Accretion ;
Photometry, millimetric/submm
Keywords: accretion, accretion disk - protoplanetary disk -
circumstellar matter - planet and satellites: formation
Abstract:
Transition disks are protoplanetary disks with inner depleted dust
cavities and excellent candidates to investigate the dust evolution
under the existence of a pressure bump. A pressure bump at the outer
edge of the cavity allows dust grains from the outer regions to stop
their rapid inward migration towards the star and efficiently grow to
millimetre sizes. Dynamical interactions with planet(s) have been one
of the most exciting theories to explain the clearing of the inner
disk.
We look for evidence of the presence of millimetre dust particles in
transition disks by measuring their spectral index αmm with
new and available photometric data. We investigate the influence of
the size of the dust depleted cavity on the disk integrated millimetre
spectral index.
We present the 3-millimetre (100GHz) photometric observations carried
out with Plateau de Bure Interferometer of four transition disks:
LkHα 330, UX Tau A, LRLL 31, and LRLL 67. We use available
values of their fluxes at 345GHz to calculate their spectral index,
as well as the spectral index for a sample of twenty transition disks.
We compare the observations with two kind of models. In the first set
of models, we consider coagulation and fragmentation of dust in a disk
in which a cavity is formed by a massive planet located at different
positions. The second set of models assumes disks with truncated inner
parts at different radius and with power-law dust size distributions,
where the maximum size of grains is calculated considering turbulence
as the source of destructive collisions.
We show that the integrated spectral index is higher for transition
disks (TD) than for regular protoplanetary disks (PD) with mean values
of <αmmTD≥2.70±0.13 and <αmmPD≥2.20±0.07
respectively. For transition disks, the probability that the measured
spectral index is positively correlated with the cavity radius is
95%. High angular resolution imaging of transition disks is needed to
distinguish between the dust trapping scenario and the truncated disk
case.
Description:
3 millimetre photometric maps carried out with Plateau de Bure
Interferometer of four transition disks: LkHα 330, UX Tau A,
LRLL 31, and LRLL 67.
Objects:
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RA (2000) DE Designation(s)
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03 45 48.28 +32 24 11.9 LkHα 330 = LkHa 330
03 44 18.17 +32 04 57.0 LRLL 31 = Cl* IC 348 LRL 31
03 43 44.61 +32 08 17.8 LRLL 67 = Cl* IC 348 LRL 67
04 30 03.99 +18 13 49.4 UX Tau A = HD 285846
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 68 4 List of FITS maps
maps/* . 4 Individual FITS maps
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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- 23 F4.2 arcsec/pix Scale [0.88/0.92] Scale of the image
25- 27 I3 pix Nx [128] Number of pixels along X-axis
28 A1 --- --- [x]
29- 31 I3 pix Ny [128] Number of pixels along Y-axis
33- 44 A12 --- FileName Name of FITS file in subdirectory maps
47- 68 A22 --- Title Title of the map
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Acknowledgements:
Paola Pinilla, pinilla(at)strw.leidenuniv.nl
(End) Patricia Vannier [CDS] 05-Mar-2014