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J/A+A/606/L3        Barnard 1b CO, NH2D and SO images          (Fuente+, 2017)

Chemical segregation in the young protostars Barnard 1b-N and S: Evidence of pseudo-disk rotation in Barnard 1b-S. Fuente A., Gerin M., Pety J., Commercon B., Agundez M., Cernicharo J., Marcelino N., Roueff E., Lis D.C., Wootten H.A. <Astron. Astrophys. 606, L3 (2017)> =2017A&A...606L...3F (SIMBAD/NED BibCode)
ADC_Keywords: Molecular clouds ; Interferometry Keywords: astrochemistry - ISM: clouds - ISM: individual objects: Barnard 1b - stars: formation - stars: low mass - ISM: kinematics and dynamics Abstract: The extremely young Class 0 object B1b-S and the first hydrostatic core (FSHC) candidate, B1b-N, provide a unique opportunity to study the chemical changes produced in the elusive transition from the prestellar core to the protostellar phase. We present 40"x70" images of Barnard 1b in the 13CO 1-0, C18O 1-0, NH2D 1(1,1)a-1(0,1)s, and SO 3(2)-2(1) lines obtained with the NOEMA interferometer. The observed chemical segregation allows us to unveil the physical structure of this young protostellar system down to scales of ∼500au. The two protostellar objects are embedded in an elongated condensation, with a velocity gradient of ∼0.2-0.4m/s/au in the east-west direction, reminiscent of an axial collapse. The NH2D data reveal cold and dense pseudo-disks (R∼500-1000au) around each protostar. Moreover, we observe evidence of pseudo-disk rotation around B1b-S. We do not see any signature of the bipolar outflows associated with B1b-N and B1b-S, which were previously detected in H2CO and CH3OH, in any of the imaged species.The non-detection of SO constrains the SO/CH3OH abundance ratio in the high-velocity gas. Description: Integrated intensity images (NOEMA+30m) of the 13CO 1-0, C18O 1-0, SO 3(2)-2(1) and NH2D 1(1,1)a-1(0,1)s lines. Units are K.km/s. These images are shown in Fig. 1. Objects: ------------------------------------------------------ RA (2000) DE Designation(s) ------------------------------------------------------ 03 33 20.32 +31 07 21.5 Barnard 1b = [HKM99] B1-b ------------------------------------------------------ File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file list.dat 80 4 List of fits images fits/* 0 4 Individual fits images
See also: J/A+A/577/L2 : Barnard 1b-N and 1b-S nascent bipolar outflows (Gerin+, 2015) J/A+A/606/A35 : Barnard 1b-N and 1b-S 350GHz images (Gerin+, 2017) 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- 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- 40 A9 --- FileName Name of FITS file, in subdirectory fits 42- 80 A39 --- Title Title of the FITS file
Acknowledgements: Asuncion Fuente, a.fuente(at)oan.es
(End) Asuncion Fuente [OAN, Spain], Patricia Vannier [CDS] 26-Sep-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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