J/ApJS/165/338 Radio recombination lines in HII regions (Quireza+, 2006)
Radio recombination lines in Galactic H II regions.
Quireza C., Rood R.T., Balser D.S., Bania T.M.
<Astrophys. J. Suppl. Ser., 165, 338-359 (2006)>
=2006ApJS..165..338Q 2006ApJS..165..338Q
ADC_Keywords: H II regions ; Radio lines ; Radial velocities
Keywords: H II regions - ISM: abundances - ISM: atoms - ISM: clouds -
ISM: evolution - ISM: lines and bands - ISM: structure -
nuclear reactions, nucleosynthesis, abundances - radio lines: ISM
Abstract:
We report radio recombination line (RRL) and continuum observations of
a sample of 106 Galactic HII regions made with the NRAO 140 Foot (43m)
radio telescope in Green Bank, West Virginia. We believe this to be
the most sensitive RRL survey ever made for a sample this large. Most
of our source integration times range between 6 and 90 hr, yielding
typical rms noise levels of ∼1.0-3.5mK. Our data result from two
different experiments performed, calibrated, and analyzed in similar
ways. A CII survey was made at the 3.5cm wavelength to obtain accurate
measurements of carbon radio recombination lines. When combined with
atomic (CI) and molecular (CO) data, these measurements will constrain
the composition, structure, kinematics, and physical properties of the
photodissociation regions that lie on the edges of HII regions. A
second survey was made at the 3.5cm wavelength to determine the
abundance of 3He in the interstellar medium of the Milky Way.
Together with measurements of the 3He+ hyperfine line, we get
high-precision RRL parameters for H, 4He, and C. Here we discuss
significant improvements in these data with both longer integrations
and newly observed sources.
Description:
Our spectral line observations were made with the NRAO 140 Foot radio
telescope during the following periods: 1996 September and December;
1997 January, August, and September; and 1998 January, June, and July.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 89 119 Properties of Galactic HII Regions
table2.dat 59 119 Hydrogen Radio Recombination Line Parameters
table3.dat 59 119 Helium Radio Recombination Line Parameters
table4.dat 64 121 Carbon Radio Recombination Line Parameters
table5.dat 84 119 Radio Emission Continuum Parameters
(Total Power Observing Mode)
table6.dat 84 119 Radio Emission Continuum Parameters
(Switched Power Observing Mode)
--------------------------------------------------------------------------------
See also:
J/A+A/397/213 : Galactic HII regions (Paladini+, 2003)
J/AJ/130/156 : Galactic radio compact HII regions at 1.4GHz (Giveon+, 2005)
J/ApJ/582/756 : Velocities of HII regions (Kolpak+, 2003)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Name Galactic HII region name
14- 16 A3 --- f_Name [a,b ] Note on the observation of Name (G1)
18- 30 A13 --- OName Other name
32- 38 F7.3 deg GLON Galactic longitude
40- 46 F7.3 deg GLAT Galactic latitude
48- 49 I2 h RAh Hour of Right Ascension (B1950)
51- 52 I2 min RAm Minute of Right Ascension (B1950)
54- 57 F4.1 s RAs Second of Right Ascension (B1950)
59 A1 --- DE- Sign of the Declination (B1950)
60- 61 I2 deg DEd Degree of Declination (B1950)
63- 64 I2 arcmin DEm Arcminute of Declination (B1950)
66- 69 F4.1 arcsec DEs Arcsecond of Declination (B1950)
71- 75 F5.1 h Tint Integration time corresponding to the spectral
line data
77- 81 F5.2 mK rms Data rms corresponding to the spectral line
data
83 A1 --- QF [A-E] Spectral line quality factor (1)
85- 89 A5 --- Survey Survey type (C II or 3He)
--------------------------------------------------------------------------------
Note (1): QF is an evaluation of the quality of the parameters measured for
the spectra as a whole. It is based on the signal-to-noise ratio, the
structure of the baseline, the crowding of spectral lines, and the
accuracy of the Gaussian fit to the line shape. A = our best spectra
to E = our worse cases.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table[234].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Name Galactic HII region name
14- 16 A3 --- f_Name [a,b ] Note on the observation of Name (G1)
20- 26 F7.2 mK TL ? Peak intensity of antenna temperature
28- 32 F5.2 mK e_TL ? Error in TL
34- 38 F5.2 km/s FWHM ? Line width full width at half maximum
40- 44 F5.2 km/s e_FWHM ? Error in FWHM
46- 51 F6.2 km/s VLSR ? LSR radial velocity (G2)
53- 57 F5.2 km/s e_VLSR ? Error in VLSR
59 A1 --- QF [A-E] Line quality factor (1)
61- 62 A2 --- Morph Spectral line shape morphology (2)
64 A1 --- RF [EGFP] Line reliability factor (3)
--------------------------------------------------------------------------------
Note (1): QF is a qualitative evaluation of the quality of the parameters
measured for the line from A (best spectra) to E (worse cases).
Mostly based in the accuracy of the Gaussian fit to the line shape.
Note (2): See text. It indicates the position (velocity) of the C line in
the spectra and how distinct it is from the He line as follows:
r = resolved
sb = semi-blended
b = blended
Note (3): RF is a qualitative evaluation of the reality of a C line as follows:
E = excellent
G = good
F = fair
P = poor
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table[56].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Name Galactic HII region name
14- 16 A3 --- f_Name [a,b ] Note on the observation of Name (G1)
18- 23 F6.3 K TC-RA ? Peak continuum intensity of antenna
temperature along Right Ascension
25- 29 F5.3 K e_TC-RA ? Error in TC-RA
31- 36 F6.3 K TC-DE ? Peak continuum intensity of antenna
temperature along Declination
38- 42 F5.3 K e_TC-DE ? Error in TC-DE
44- 49 F6.3 arcmin PA-RA ? FWHM observed angular size along Right
Ascension
51- 55 F5.3 arcmin e_PA-RA ? Error in PA-RA
57- 62 F6.3 arcmin PA-DE ? FWHM observed angular size along Declination
64- 69 F6.3 arcmin e_PA-DE ? Error in PA-DE
71- 76 F6.3 arcmin PA-src ? Geometric mean FWHM observed angular size
78- 82 F5.3 arcmin e_PA-src ? Error in PA-src
84 A1 --- QF [A-E] Continuum quality factor (1)
--------------------------------------------------------------------------------
Note (1): See text. QF is an evaluation of the quality of the parameters
measured for the continuum scans from A (best spectra) to E (worse
cases). It is based on the accuracy of the Gaussian fit to the
emission feature, the uncertainty in the baseline models and the
contrast between the target source emission and any emission from
possible sub-structures or nearby confusing sources.
--------------------------------------------------------------------------------
Global notes:
Note (G1): Flags as follows:
a = M16, M17, NGC 6334, Rosette and S209 were observed at different
positions in the 3He survey.
b = Observed in the C II survey.
c = Observed in the 3He survey.
Note (G2): Relative to the Local Standard of Rest. The 140 Foot velocities
cited here are in the kinematic LSR frame using the radio definition
of the Doppler shift. The kinematic LSR is defined by a Solar motion
of 20.0km/s towards (RA,Dec)=(18h,+30deg)[1900.0].
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 14-Dec-2007