J/other/AcApS/18.302 Molecular clouds in 8<l<38, -1<b<+1 (Sun+, 1998)
Molecular clouds in different evolutionary stages and star formation
Sun Y.-C., Sun J.
<Acta Astrophys. Sinica, 18, 302 (1998)>
=1998AcApS..18..302S 1998AcApS..18..302S
ADC_Keywords: H II regions ; Infrared sources
Keywords: molecular clouds - star formation - H II regions -
infrared point sources
Abstract:
A systematic comparison between molecular clouds in different
evolutionary stages and processes of star formation is made over the
range of 8° to 38° in Galactic longitude and -1° to
+1° in Galactic latitude by using the Massachusetts-Stony Brook
Survey data of 12CO in the Galactic plane (HPFW=47") and the IRAS
Infrared Sky Survey image data (1.5' per pixel). This region is
divided into thirty subregions. Then, the space distribution of
CO(1-0) emission and the corresponding infrared intensity at 60ymis
obtained for each subregion, and the contours of infrared color
temperatures and optical depths of molecular cloud complexes in the
corresponding regions are calculated and derived. Moreover, the
catalogs of the IRAS infrared point sources and HII regions are used.
Thus, molecular clouds in different evolutionary stages are identified
and divided into four groups ranging from young clouds to evolved
clouds, and their main characteristics and relations to the processes
of star formation are analysed. The Galatic-longitude distributions of
ultracompact HII regions and candidate protostars as well as the ratio
between HII region-molecular cloud and candidate protostar-molecular
cloud associations are analysed statistically. The results indicate
that star formation activities are currently still going on in our
Galaxy.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 12 89 Ultracompact HII regions
table2.dat 12 120 120 protostar candidates
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See also:
II/125 : IRAS catalogue of Point Sources, Version 2.0 (IPAC 1986)
VII/20 : Catalogue of HII Regions (Sharpless 1959)
Byte-by-byte Description of file: table1.dat table2.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Object designation (HHMMd+DDMM)
12 A1 --- m_Name [A] Multiplicity index on Name
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History: Prepared via OCR at CDS.
(End) James Marcout, Patricia Bauer [CDS] 24-Aug-1999