J/A+A/665/A63 DR20 integrated intensity maps (Beuther+, 2022)
The Cygnus Allscale Survey of Chemistry and Dynamical Environments: CASCADE.
Overview and first results towards DR20 from the Max Planck IRAM Observatory
program (MIOP).
Beuther H., Wyrowski F., Menten K.M., Winters J.M., Suri S., Kim W.-J.,
Bouscasse L., Gieser C., Sawczuck M., Christensen I.B., Skretas I.M.
<Astron. Astrophys. 665, A63 (2022)>
=2022A&A...665A..63B 2022A&A...665A..63B (SIMBAD/NED BibCode)
ADC_Keywords: Molecular clouds ; H II regions
Keywords: stars: formation - ISM: clouds - ISM: kinematics and dynamics -
ISM: individual objects: Cygnus X - ISM: individual objects: DR20
Abstract:
While star formation on large molecular cloud scales and on small core
and disk scales has been investigated intensely over the past decades,
the connection of the large-scale interstellar material with the
densest small-scale cores has been a largely neglected field.
We wish to understand how the gas is fed from clouds down to cores.
This covers dynamical accretion flows as well as the physical and
chemical gas properties over a broad range of spatial scales.
Using the IRAM facilities NOEMA and the IRAM 30m telescope, we mapped
large areas (640-arcmin2) of the archetypical star formation complex
Cygnus X at 3.6mm wavelengths in line and continuum emission. The
data were combined and imaged together to cover all accessible spatial
scales.
The scope and outline of The Cygnus Allscale Survey of Chemistry and
Dynamical Environments (CASCADE) as part of the Max Planck IRAM
Observatory Program (MIOP) is presented. We then focus on the first
observed subregion in Cygnus X, namely the DR20 star formation site,
which comprises sources in a range of evolutionary stages from cold
pristine gas clumps to more evolved ultracompact HII regions. The data
covering cloud to cores scales at a linear spatial resolution of
<5000au reveal several kinematic cloud components that may be part of
several large-scale flows around the central cores. The temperature
structure of the region is investigated by means of the HCN/HNC
intensity ratio and compared to dust-derived temperatures. We find
that the deuterated DCO+ emission is almost exclusively located
toward regions at low temperatures below 20K. Investigating the slopes
of spatial power spectra of dense gas tracer intensity distributions
(HCO+, H13CO+, and N2H+), we find comparatively flat slopes between
∼2.9 and ∼2.6, consistent with high Mach numbers and/or active
star formation in DR20.
This MIOP large program on star formation in Cygnus X provides unique
new data connecting cloud with core scales. The analysis of the DR20
data presented here highlights the potential of this program to
investigate in detail the different physical and chemical aspects and
their interrelations from the scale of the natal molecular cloud down
to the scale of accretion onto the individual protostellar cores.
Description:
The three mosaic tiles of the DR20 region were observed individually
with NOEMA in the C and D configurations between 2019 December 15 and
2020 May 3, with typically ten antennas in the array (baselines
between ∼15 and ∼365m). Each mosaic tile consists of 78 pointings.
The phase reference centers (in J2000.0) of the three fields are
RA 20:36:47.570 Dec +41:36:50.40, RA 20:37:05.437 Dec +41:34:10.40, and
RA 20:37:23.303 Dec +41:34:10.40.
Objects:
-----------------------------------------------
RA (2000) DE Designation(s)
-----------------------------------------------
20 36 55.9 +41 36 29 DR20 = GAL 080.8+00.4
-----------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
list.dat 120 35 List of fits images and datacubes
fits/* . 35 Individual fits images and datacubes
--------------------------------------------------------------------------------
Byte-by-byte Description of file: list.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 23 I4 --- Nx Number of pixels along X-axis
25- 28 I4 --- Ny Number of pixels along Y-axis
30- 31 I2 --- Nz ? Number of slices
33- 38 I6 Kibyte size Size of FITS file
40- 69 A30 --- FileName Name of FITS file, in subdirectory fits
71-120 A50 --- Title Title of the FITS file
--------------------------------------------------------------------------------
Acknowledgements:
Henrik Beuther, beuther(at)mpia.de
(End) Patricia Vannier [CDS] 18-Jul-2022