J/ApJS/211/29 Atlas of HI absorption toward HII regions in SGPS I (Brown+, 2014)
A complete atlas of H I absorption toward H II regions in the Southern
Galactic Plane Survey (SGPS I).
Brown C., Dickey J.M., Dawson J.R., McClure-Griffiths N.M.
<Astrophys. J. Suppl. Ser., 211, 29 (2014)>
=2014ApJS..211...29B 2014ApJS..211...29B
ADC_Keywords: H II regions ; H I data ; Galactic plane ; Surveys
Keywords: H II regions
Abstract:
We present a complete catalog of H I emission and absorption spectrum
pairs, toward H II regions, detectable within the boundaries of the
Southern Galactic Plane Survey (SGPS I), a total of 252 regions. The
catalog is presented in graphical, numerical, and summary formats. We
demonstrate an application of this new data set through an
investigation of the locus of the Near 3kpc Arm.
Description:
The SGPS covers 325deg2 of the Galactic plane over the fourth and
first Galactic quadrants (SGPS I and SGPS II, respectively). The SGPS
provides three distinct data products: Parkes continuum-subtracted
cubes, with an angular resolution of 15', combined Parkes and ATCA
continuum-subtracted HI cubes (2.2'), and combined Parkes and ATCA
cubes containing continuum emission (∼1.6'). For this work we use the
continuum-included combined Parkes-ATCA data. These cubes were
specifically produced for HI absorption studies, as they provide
accurately calibrated data at the highest angular resolution of the
SGPS. All SGPS continuum and line cube data are available online via
the Australia Telescope National Facility (ATNF) HI Surveys archive.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 61 252 HII region catalog
data/* . 245 Individual files in ASCII format of HI
emission/absorption spectrum for each HII region
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See also:
VIII/58 : A Survey of Radio H II Regions in the Northern Sky (Lockman+ 1989)
J/MNRAS/420/1656 : RMS compact HII regions distances (Urquhart+, 2012)
J/ApJ/753/62 : Kinematic distance ambiguity in HII regions (Jones+, 2012)
J/ApJ/699/1153 : Kinematic dist. to GRS molecular clouds (Roman-Duval+, 2009)
J/ApJS/165/338 : Radio recombination lines in HII regions (Quireza+, 2006)
J/ApJ/626/195 : HI self-absorption (HISA) survey in the CGPS (Gibson+, 2005)
J/ApJ/626/887 : HI clouds in Southern Galactic Plane Survey (Kavars+, 2005)
J/ApJ/582/756 : Velocities of HII regions (Kolpak+, 2003)
J/A+A/171/261 : RRLs of Southern HII Regions (Caswell+ 1987)
J/MNRAS/201/495 : HI Survey of Southern Galactic Plane (Strong+ 1982)
http://www.atnf.csiro.au/research/HI/common/ : ATNF HI archive
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 F7.3 deg GLON [254.6/353.2] Galactic Longitude
9- 14 F6.3 deg GLAT [-1.3/1.5] Galactic Latitude
16- 38 A23 --- Name Simbad identifier for this region
40 A1 --- Q [A-F] Quality factor (A=best) (1)
42- 45 I4 K Tcont [5/1377] Continuum temperature
47- 52 F6.1 km/s Vrrl1 [-122/66] First RRL (radio recombination
lines) velocity
54- 59 F6.1 km/s Vrrl2 ? Second RRL velocity
61 I1 --- Ref Source reference code (2)
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Note (1): A series of five tests were devised to measure the quality of
each HI absorption spectrum (see Figure 2) - resulting in six quality
categories A-F. See section 3.2 for further explanations.
Note (2): Reference as follows:
1 = Caswell & Haynes (1987, Cat. J/A+A/171/261);
2 = Bania et al. (2010ApJ...718L.106B 2010ApJ...718L.106B);
3 = Lockman (1989, Cat. VIII/58);
4 = Wilson et al. (1970A&A.....6..364W 1970A&A.....6..364W).
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Byte-by-byte Description of file: data/*
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Bytes Format Units Label Explanations
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1- 7 F7.2 km/s Vel [-227.6/265.5] Velocity channel
9- 16 F8.2 K Ton On source brightness temperature (Ton)
18- 25 F8.2 K Toff Average of the three off source brightness
temperatures (i.e., the emission spectrum)
27- 33 F7.2 K e_Toff Toff uncertainty (1)
35- 39 F5.2 --- tau Absorption value τ [exp(-τ)=(Ton-Toff)/Tcont]
41- 45 F5.2 --- e_tau Absorption uncertainty envelope (Δabs)
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Note (1): The uncertainty in Toff, caused by the differences
in the three off source positions, 3σ(Toff)
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 07-May-2014