J/A+A/677/A107 3D kinetic tomography of Taurus clouds (Duchene+, 2023)
Toward a 3D kinetic tomography of Taurus clouds:
II. A new automated technique and its validation.
Duchene Q., Hottier C., Lallement R., Vergely J.L., Babusiaux C.,
Marchal A., Arenou F.
<Astron. Astrophys. 677, A107 (2023)>
=2023A&A...677A.107D 2023A&A...677A.107D (SIMBAD/NED BibCode)
ADC_Keywords: Molecular clouds ; Stars, distances ; Radial velocities
Keywords: dust: extinction - ISM: lines and bands - ISM: structure -
local insterstellar matter
Abstract:
Three-dimensional (3D) kinetic maps of the Milky Way interstellar
medium are an essential tool in studies of its structure and of star
formation.
We aim to assign radial velocities to Galactic interstellar clouds now
spatially localized based on starlight extinction and star distances
from Gaia and stellar surveys.
We developed an automated search for coherent projections on the sky
of clouds isolated in 3D extinction density maps on the one hand, and
regions responsible for CO radio emissions at specific Doppler shifts
on the other hand. The discrete dust structures were obtained by
application of the Fellwalker algorithm to a recent 3D extinction
density map. For each extinction cloud, a technique using a narrow
sliding spectral window moved along the contour-bounded CO spectrum
and geometrical criteria was used to select the most likely velocity
interval.
We applied the new contour-based technique to the 3D extinction
density distribution within the volume encompassing the Taurus,
Auriga, Perseus, and California molecular complexes. From the 45
clouds issued from the decomposition, 42 were assigned a velocity. The
remaining structures correspond to very weak CO emission or
extinction. We used the non-automated assignments of radial velocities
to clouds of the same region presented in Paper I (Ivanova et al.,
2021A&A...652A..22I 2021A&A...652A..22I) and based on KI absorption spectra as a
validation test. The new fully automated determinations were found to
be in good agreement with these previous measurements.
Our results show that an automated search based on cloud-contour
morphology can be efficient and that this novel technique may be
extended to wider regions of the Milky Way and at larger distance. We
discuss its limitations and potential improvements after combination
with other techniques.
Description:
We present the results of our automated radial velocity assignation
method applied on the molecular clouds of the Taurus region. This
method makes use of Dame et al. (2001ApJ...547..792D 2001ApJ...547..792D) survey data and
extinction maps from Lallement et al. (2022A&A...661A.147L 2022A&A...661A.147L,
Cat. J/A+A/661/A147) and Vergely et al. (2022A&A...664A.174V 2022A&A...664A.174V,
Cat. J/A+A/664/A174).
This table contains the 3D position and assigned LSR velocity of each
channel barycenter of the clumps described in the paper. Galactic
longitude, Galactic latitude, Distance of the barycenter from the Sun
and LSR radial velocity.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 34 38214 3D position and assigned LSR velocity of
each channel barycenter of the clumps
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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2- 6 I5 --- Index Index of the channel barycenter
8- 14 F7.3 deg GLON Galactic longitude
16- 22 F7.3 deg GLAT Galactix latitude
24- 28 F5.1 pc Dist Distance from the Sun
30- 34 F5.1 km/s vLSR LSR radial velocity
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Acknowledgements:
Quentin Duchene, quentin.duchene(at)obspm.fr
References:
Ivanova et al., Paper I 2021A&A...652A..22I 2021A&A...652A..22I
(End) Patricia Vannier [CDS] 14-Apr-2023