J/A+A/589/A60 CO, SO and H2CO images of AB Aur (Pacheco-Vazquez+, 2016)
High spatial resolution imaging of SO and H2CO in AB Auriga:
The first SO image in a transitional disk.
Pacheco-Vazquez S., Fuente A., Baruteau C., Berne O., Agundez M., Neri R.,
Goicoechea J.R., Cernicharo J., Bachiller R.
<Astron. Astrophys. 589, A60 (2016)>
=2016A&A...589A..60P 2016A&A...589A..60P (SIMBAD/NED BibCode)
ADC_Keywords: Stars, pre-main sequence ; Radio lines ; Interferometry
Keywords: stars: individual: AB Aur - circumstellar matter -
stars: pre-main sequence - stars: variables: T Tauri, Herbig Ae/Be -
stars: formation - planetary systems
Abstract:
Transitional disks are structures of dust and gas around young stars
with large inner cavities in which planet formation may occur.
Lopsided dust distributions are observed in the dust continuum
emission at millimeter wavelengths. These asymmetrical structures can
be explained as being the result of an enhanced gas density vortex
where the dust is trapped, potentially promoting the rapid growth to
the planetesimal scale.
AB Aur hosts a transitional disk with a clear horseshoe morphology
which strongly suggests the presence of a dust trap. Our goal is to
investigate its formation and the possible effects on the gas
chemistry.
We used the NOrthern Extended Millimeter Array (NOEMA) interferometer
to image the 1mm continuum dust emission and the 13CO J=2->1,
C18O J=2->1, SO J=56->45, and H2CO J=303->202.
rotational lines.
Description:
The interferometric observations were carried out with the NOEMA
interferometer in CD configuration between October and December, 2014
with six antennas providing the angular resolution and rms shown in
Table 1. We targeted AB Aur (RA(J2000)=04:55:45.8,
DE(J2000)=30:33:04.2) to simultaneously observe the H2CO
J=30,3->20,2 line at 218.222GHz, the SO J=56->45 line at
219.949GHz, the C18O J=2->1 line at 219.560GHz, and the 13CO
J=2->1 line at 220.398GHz. The beam size was 1.6x1.5. The channels
free of line emission were used to estimate the continuum flux that
was subtracted from the spectral maps. To improve the signal-to-noise
ratio (S/N), all maps were created with a velocity resolution of
0.25km/s.
We used 3C 84, 3C 454.3, MWC 349, J0433, and J0418 as phase and flux
calibrators. The uncertainty in the calibration is about 10%. Data
reduction and image synthesis were carried out using the GILDAS
software.
Objects:
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RA (2000) DE Designation(s)
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04 55 45.85 +30 33 04.3 AB Aur = HD 31293
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 124 5 List of fits images
fits/* . 5 Individual fits images
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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- 22 I3 --- Nx Number of pixels along X-axis
24- 26 I3 --- Ny Number of pixels along Y-axis
28- 30 I3 Kibyte size Size of FITS file
32- 47 A16 --- FileName Name of FITS file, in subdirectory fits
49-124 A76 --- Title Title of the FITS file
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Acknowledgements:
Susana Pacheco, s.pacheco(at)oan.es
(End) Patricia Vannier [CDS] 20-Apr-2016