J/A+A/633/A82 Disks around T Tauri stars with SPHERE. II. (Garufi+, 2020)
Disks around T Tauri stars with SPHERE (DARTTS-S).
II: Twenty-one new polarimetric images of young stellar disks.
Garufi A., Avenhaus H., Perez S., Quanz S.P., van Holstein R.G.,
Bertrang G.H.-M., Casassus S., Cieza L., Principe D.A., van der Plas G.,
Zurlo A.
<Astron. Astrophys. 633, A82 (2020)>
=2020A&A...633A..82G 2020A&A...633A..82G (SIMBAD/NED BibCode)
ADC_Keywords: Stars, pre-main sequence ; Infrared sources
Keywords: protoplanetary disks - techniques: polarimatric -
stars: pre-main sequence
Abstract:
Near-IR polarimetric images of protoplanetary disks provide the
ability to characterize sub-structures that are potentially due to the
interaction with (forming) planets. The available census is, however,
strongly biased toward massive disks around old stars.
The DARTTS program aims at alleviating this bias by imaging a large
number of T Tauri stars with diverse properties.
DARTTS-S employs VLT/SPHERE to image the polarized scattered light
from disks. In parallel, DARTTS-A is providing ALMA images of the same
targets for a comparison of different dust components. In this work, we
present new SPHERE images of 21 circumstellar disks, which is the
largest sample of this time yet to be released. A re-calculation of
some relevant stellar and disk properties following Gaia DR2 is also
performed.
The targets of this work are significantly younger than those
published thus far with polarimetric NIR imaging. Scattered light is
unambiguously resolved in 11 targets while some polarized unresolved
signal is detected in 3 additional sources. Some disk sub-structures
are detected. However, the paucity of spirals and shadows from this
sample reinforces the trend for which these NIR features are
associated with Herbig stars, either because older or more massive.
Furthermore, disk rings that are apparent in ALMA observations of some
targets do not appear to have corresponding detections with SPHERE.
Inner cavities larger than 15au are also absent from our images
despite being expected from the SED. On the other hand, 3 objects show
extended filaments at larger scale that are indicative of strong
interaction with the surrounding medium. All but one of the undetected
disks are best explained by their limited size (≲20au) and the high
occurrence of stellar companions in these sources suggest an important
role in limiting the disk size. One undetected disk is massive and
very large at millimeter wavelengths implying it is self-shadowed in
the near-IR.
This work paves the way towards a more complete and less biased sample
of scattered-light observations, which is required to interpret how
disk features evolve throughout the disk lifetime.
Description:
H-band Qphi images of the sample, as from the Fig. 1 of the paper.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 136 10 List of fits files
fits/* . 10 Individual 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- 2 I2 h RAh Right Ascension of center (J2000)
4- 5 I2 min RAm Right Ascension of center (J2000)
7- 11 F5.2 s RAs Right Ascension of center (J2000)
12 A1 --- DE- Declination sign (J2000)
13- 14 I2 deg DEd Declination (J2000)
16- 17 I2 arcmin DEm Declination (J2000)
19- 22 F4.1 arcsec DEs Declination (J2000)
24- 27 I4 --- Nx Number of pixels along X-axis
29- 32 I4 --- Ny Number of pixels along Y-axis
34- 37 I4 Kibyte size Size of FITS file
39- 98 A60 --- FileName Name of FITS file, in subdirectory fits
100-136 A37 --- Title Title of the FITS file
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Acknowledgements:
Antonio Garufi, agarufi(at)arcetri.astro.it
References:
Avenhaus et al., Paper I 2018ApJ...863...44A 2018ApJ...863...44A
(End) Patricia Vannier [CDS] 26-Nov-2019