J/A+A/501/539 RMS survey. 6cm observations of YSOs (Urquhart+, 2009)
The RMS survey. 6 cm continuum VLA observations towards candidate massive YSOs
in the northern hemisphere.
Urquhart J.S., Hoare M.G., Purcell C.R., Lumsden S.L., Oudmaijer R.D.,
Moore T.J.T., Busfield A.L., Mottram J.C., Davies B.
<Astron. Astrophys., 501, 539-551 (2009)>
=2009A&A...501..539U 2009A&A...501..539U
ADC_Keywords: YSOs ; Radio sources ; Infrared sources ; Morphology
Keywords: radio continuum: ISM - stars: formation - stars: early-type -
stars: pre-main sequence
Abstract:
The Red MSX Source (RMS) survey is an ongoing multi-wavelength
observational programme designed to return a large, well-selected
sample of massive young stellar objects (MYSOs). We have identified
∼2000 MYSO candidates located throughout the Galaxy by comparing
the colours of MSX and 2MASS point sources to those of known MYSOs.
The aim of these follow-up observations is to identify other objects
with similar colours such as ultra compact (UC) HII regions, evolved
stars and planetary nebulae (PNe) and distinguish between genuine
MYSOs and nearby low-mass YSOs.
To identify the populations of UCHII regions and PNe within the sample
and examine their Galactic distribution.
We have conducted high resolution radio continuum observations at 6cm
towards 659 MYSO candidates in the northern hemisphere
(10°<l<250°) using the Very Large Array (VLA). These
observations have a spatial resolution of ∼1-2" and typical image rms
noise values of ∼0.22mJy - sensitive enough to detect a HII region
powered by B0.5 star at the far side of the Galaxy. In addition to
these targeted observations we present archival data towards a further
315 RMS sources extracted from a previous VLA survey of the inner
Galaxy.
Description:
Results of a set of VLA observations towards an MSX and 2MASS colour
selected sample of massive young stellar candidates.
Table 3: Field names, positions, observational rms values;
Table 4: detected radio sources their parameters and associated MSX
point sources; Table 5: RMS-radio matches.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 49 1068 Field positions and restoring beam parameters
table4.dat 107 669 VLA radio detection catalogue
table5.dat 105 344 Parameters for radio sources found to be
associated with RMS sources
fig2/* . 2007 *Images (1'x1') of all radio sources detected by
these targeted VLA observations for table4 sources
(files in FITS, EPS and PNG format)
fig4/* . 544 *Contour maps of the RMS-radio matches found from
the targeted VLA observations and those found
in the White et al. (2005, J/AJ/130/586)
catalogue for table5 sources
(files in EPS and PNG format)
fig7/* . 404 *Examples of the different types of radio loud
RMS sources identified for some table5 sources
(files in EPS and PNG format)
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Note on fig2/*: The source name is printed above each image and shape and
orientation of the restoring beam is shown in the lower left corner.
Note on fig4/*: The first contour starts at 4σ with the intervening
levels determined by a dynamic power-law which is given in the lower
right corner of each plot (see text for details). The RMS name is
shown above the image and the size of the synthesised beam is shown to
scale in the lower left hand corner. The position of the RMS source is
marked with a cross.
Note on fig7/*: In the top and centre panels we present four HII regions
chosen to illustrate the difference kinds of morphologies identified
and in the bottom two panels we present an unresolved (left) and
resolved (right) PN. These images are composed of the GLIMPSE 3.6, 4.5
and 8.0um bands (coloured blue, green and red respectively) which are
overlaid with contours of the detected radio emission (contour levels
are as for Fig. 4).
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See also:
V/114 : MSX6C Infrared Point Source Catalog (Egan+ 2003)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/AJ/130/586 : Compact radio sources in the galactic plane (White+, 2005)
J/A+A/461/11 : Radio observations of MYSO candidates (Urquhart+, 2007)
J/A+A/474/891 : 13CO observations of YSOs in South Gal. plane (Urquhart+, 2007)
J/A+A/487/253 : The RMS survey: 13CO observations of YSOs (Urquhart+ 2008)
http://www.ast.leeds.ac.uk/RMS : RMS Home Page
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Field Field name (GLLL.llll+BB)
14- 21 F8.4 deg RAdeg Right ascension (J2000) field centre
23- 30 F8.4 deg DEdeg Declination (J2000) field centre
32- 34 F3.1 arcsec beamMaj Beam major axis
36- 38 F3.1 arcsec beamMin Beam minor axis
40- 44 F5.1 deg beamPA Beam position angle
46- 49 F4.2 mJy mJy/beam Image rms (in mJy/beam)
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- RadioName Radio name (GLLL.llll+BB.bbbb)
19- 26 F8.4 deg RAdeg Right ascension (J2000) radio source
28- 35 F8.4 deg DEdeg Declination (J2000) radio source
37- 41 F5.1 arcsec offset Offset from the field centre
43- 54 A12 --- Field Field name
56- 60 F5.1 mJy Sp Peak 6cm radio flux (5GHz)
62- 66 F5.2 mJy e_Sp Peak flux error radio
68- 73 F6.1 mJy Sint Integrated 6cm radio flux
75 A1 --- l_Maj Limit flag on Maj
76- 79 F4.1 arcsec Maj ?=- Source major axis
81- 84 F4.1 arcsec Min ?=- Source minor axis
86- 89 F4.1 arcsec MSXoff ?=- Offset from nearest MSX point source
91-107 A17 --- MSX Name of nearest MSX point source
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- MSX MSX name (GLLL.llll+BB.bbbb)
19- 35 A17 --- RadioName Radio name (1)
37- 40 F4.1 arcsec Offset Offset between RMS position and radio position
42- 49 F8.4 deg RAdeg Right ascension (J2000) of radio source
51- 58 F8.4 deg DEdeg Declination (J2000) of radio source
60- 65 F6.1 mJy Sp Peak radio flux
67- 72 F6.1 mJy Sint Integrated radio flux
74 A1 --- l_Maj Limit flag on Maj
75- 78 F4.1 arcsec Maj Source major axis
80- 83 F4.1 arcsec Min Source minor axis
85- 90 A6 --- Survey Name of Survey (2)
92-103 A12 --- Type Type of source (3)
105 A1 --- fig7 [*] indicates an image in fig7 subdirectory
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Note (1): As given by Table 4 (GLLL.llll+bb.bbbb) or White et al., 2005,
Cat. J/AJ/130/586 (LL.lll+B.bbb).
Note (2): Name of Survey is:
RMS = results presented in Table 4
MAGPIS = results presented by White et al, 2005, Cat. J/AJ/130/586
Note (3): RMS sources have been give one of five difference classifications:
HII region, PN, YSO, HII/YSO and Other. The first three of these are
obvious, however, the last two require a little explanation. The
HII/YSO classification is give to MSX sources that appear to be
associated with both an HII region and a YSO. The classification
"Other" is given to sources that do not fit into any of the other
classification.
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Acknowledgements:
James Urquhart, james.urquhart(at)csiro.au
History:
* 25-Sep-2009: on-line version
* 09-Jul-2010: correction in table5, radio position instead of RMS ones
(End) Patricia Vannier [CDS] 25-Sep-2009