J/ApJ/784/111 Morphology of candidate intermediate-mass SFRs (Lundquist+, 2014)
An all-sky sample of intermediate-mass star-forming regions.
Lundquist M.J., Kobulnicky H.A., Alexander M.J., Kerton C.R., Arvidsson K.
<Astrophys. J., 784, 111 (2014)>
=2014ApJ...784..111L 2014ApJ...784..111L (SIMBAD/NED BibCode)
ADC_Keywords: Galactic plane ; Infrared sources ; Morphology
Keywords: H II regions - stars: formation - stars: pre-main sequence - surveys
Abstract:
We present an all-sky sample of 984 candidate intermediate-mass
Galactic star-forming regions that are color selected from the
Infrared Astronomical Satellite (IRAS) Point Source Catalog and
morphologically classify each object using mid-infrared Wide-field
Infrared Survey Explorer (WISE) images. Of the 984 candidates, 616 are
probable star-forming regions (62.6%), 128 are filamentary structures
(13.0%), 39 are point-like objects of unknown nature (4.0%), and 201
are galaxies (20.4%). We conduct a study of four of these regions,
IRAS 00259+5625, IRAS 00420+5530, IRAS 01080+5717, and IRAS
05380+2020, at Galactic latitudes|b|>5° using optical spectroscopy
from the Wyoming Infrared Observatory, along with near-infrared
photometry from the Two-Micron All Sky Survey, to investigate their
stellar content. New optical spectra, color-magnitude diagrams, and
color-color diagrams reveal their extinctions, spectrophotometric
distances, and the presence of small stellar clusters containing
20-78M☉ of stars. These low-mass diffuse star clusters contain
∼65-250 stars for a typical initial mass function, including one or
more mid-B stars as their most massive constituents. Using infrared
spectral energy distributions we identify young stellar objects near
each region and assign probable masses and evolutionary stages to the
protostars. The total infrared luminosity lies in the range
190-960L☉, consistent with the sum of the luminosities of the
individually identified young stellar objects.
Description:
We present an all-sky sample of 984 candidate Intermediate-Mass
Galactic Star-Forming Regions (IM SFRs) that are color selected from
the Infrared Astronomical Satellite (IRAS) Point Source Catalog (cat.
II/125) and morphologically classify each object using mid-infrared
Wide-field Infrared Survey Explorer (WISE) 12 and 22µm images.
Table1 lists the IRAS source name, coordinates, and morphological
classification for all 984 objects in the sample.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 44 984 Intermediate-Mass Star-Forming Region (IM SFR)
sources
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See also:
II/328 : AllWISE Data Release (Cutri+ 2013)
J/AJ/140/462 : Intermediate-mass star-forming regions (Arvidsson+, 2010)
J/A+AS/104/529 : IRAS galaxies behind the Milky Way (Takata+ 1994)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/984] Running sequence number
5- 14 A10 --- IRAS IRAS identifier
16- 23 F8.4 deg GLON Galactic longitude
25- 32 F8.4 deg GLAT Galactic latitude
34- 44 A11 --- Morph Morphological classification (Blob/Shell,
Filamentary, Galaxy, or Star-like) (1)
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Note (1): Scheme of Arvidsson et al. 2010 (cat. J/AJ/140/462) defined as below:
Blobs/Shell = Characterized by extended emission at 12 and 22µm,
including isolated blobs, shells, and enhancements at the
edges of pillars or bright-rimmed clouds;
Filamentary = The filamentary objects appear to be long, narrow,
low-surface-brightness wisps of emission at 12 and 22µm;
Star-like = The star-like objects appear as isolated point sources
(occasionally multiple) in all WISE bands;
Galaxy = The galaxies exhibit extended emission that appears circular
or lenticular in all WISE bands, but they also have extended
emission in near-infrared 2MASS and optical DSS images,
rendering their morphology unmistakable (this "galaxies"
category is a new one that we introduced to the scheme of
Arvidsson et al. 2010 (cat. J/AJ/140/462)).
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History:
From electronic version of the journal
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 01-Aug-2016