J/A+A/171/261 Radio Recombination Lines of Southern HII Regions (Caswell+ 1987)
Southern HII Regions: an extensive study of radio recombination line emission
Caswell J.L., Haynes R.F.
<Astron. Astrophys. 171, 261 (1987)>
=1987A&A...171..261C 1987A&A...171..261C
ADC_Keywords: H II regions; Radial velocities; Radio lines; Radio sources
Keywords: H II regions; radio recombination lines; galactic structure
Description:
We tabulate velocities and other parameters of hydrogen recombination
lines near 5GHz (H109α and H110α) for 316 HII regions
observed with the Parkes 64-m radio telescope. Results of a new search
for formaldehyde absorption are also listed. Source selection was
based on the 5GHz continuum southern galactic plane survey of Haynes
et al. (1978, 1979). Data is given for most H II regions in the
galactic longitude range 210 to 360 degrees that show 5GHz continuum
brightness temperature exceeding 1K (as observed with the 4 arcminute
beam of the Parkes 64-m telescope), together with a selection of
sources that are weaker or outside of this longitude range. Tabulated
data include source coordinates, peak brightness, flux density, and
angular size from the 5GHz continuum survey; radial velocities of
detected formaldehyde absorption lines; recombination line peak
brightness, radial velocity, and line width; derived electron
temperature assuming LTE; derived kinematic distance from the Sun and
galactocentric radius; and presence or absence of a visible optical
counterpart. In cases where kinematic distance is ambiguous, both near
and far distances are tabulated; a flag is given if there is a strong
preference for near or far distance based on information such as H I
or H2CO absorption measurements or visibility of an optical
counterpart. Many of these radio HII regions lie beyond the range of
optical detection, at distances exceeding several kpc; they thus
provide a comprehensive coverage of the southern HII regions in the
Galaxy over the longitude range 210 to 360 degrees and constitute a
vital data base for the study of galactic structure.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 152 317 Hydrogen recombination line data (1)
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Note (1): One of the sources in the table, G326.230+0.976, may be part of
the next source in the table, G326.315+0.689.
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 Galactic longitude (1)
8- 13 F6.3 deg GLAT Galactic latitude (1)
14 A1 --- m_V [ab]? Recombination line velocity component
16- 17 I2 h RAh Right Ascension (1950) (1)
18- 19 I2 min RAm Right Ascension (1950)
20- 23 F4.1 s RAs Right Ascension (1950)
24 A1 --- DE- Declination sign (1950)
25- 26 I2 deg DEd Declination (1950) (1)
27- 28 I2 arcmin DEm Declination (1950)
29- 30 I2 arcsec DEs Declination (1950)
32- 37 F6.2 K Tc Peak 5GHz continuum brightness temperature
38 A1 --- u_Tc [ :] Uncertainty flag on Tc
41- 44 F4.1 arcmin Diam1 ? Angular size (first dimension) (2)
45 A1 --- u_Diam1 [ :] Uncertainty flag on Diam1
48- 51 F4.1 arcmin Diam2 ? Angular size (second dimension) (2)
52 A1 --- u_Diam2 [ :] Uncertainty flag on Diam2
55- 60 F6.2 Jy S ? 5GHz continuum flux density
61 A1 --- u_S [ :] Uncertainty flag on S
62- 67 F6.1 km/s V1-H2CO ? LSR velocity of H2CO absorption line,
first velocity component
68- 73 F6.1 km/s V2-H2CO ? LSR velocity of H2CO absorption line,
second velocity component
74- 79 F6.1 km/s V3-H2CO ? LSR velocity of H2CO absorption line,
third velocity component
80- 84 F5.1 km/s V4-H2CO ? LSR velocity of H2CO absorption line,
fourth velocity component
85- 86 A2 --- nH2CO ? Note on H2CO measurements:
ND: no detectable H2CO absorption,
NA: no available H2CO measurement
88- 89 A2 --- rH2CO ? Reference for H2CO results:
CH: this survey, Caswell and Haynes (1987),
WG: Whiteoak and Gardner 1974A&A....37..389W 1974A&A....37..389W
Gardner and Whiteoak 1984MNRAS.210...23G 1984MNRAS.210...23G
91- 95 F5.3 K TL Peak recombination line brightness
temperature (3)
96 A1 --- u_TL [ :] Uncertainty flag on TL
98- 99 I2 km/s DV Width of recombination line,
full width at half intensity (3)
100 A1 --- u_DV [ :] Uncertainty flag on DV
101-104 I4 km/s V LSR velocity of recombination line (3)
105 A1 --- u_V [ :] Uncertainty flag on V
107-111 I5 K Te LTE Electron Temperature
112 A1 --- u_Te [ :] Uncertainty flag on Te
115-118 F4.1 kpc Rg ? Galactocentric radius (4)
119 A1 --- u_Rg [ :] Uncertainty flag on Rg
122-125 F4.1 kpc d1 ? Kinematic distance, or
near kinematic distance (4) (5)
126 A1 --- u_d1 [ :] Uncertainty flag on d1
128-131 F4.1 kpc d2 ? Far kinematic distance (4) (5)
133 A1 --- f_d1 ? Near/far preference flag,
N: near kinematic distance
is significantly more likely,
F: far kinematic distance
is significantly more likely
135-136 A2 --- n_d1 ? HI absorption flag,
HI: near/far preference is based on
21 cm absorption line data
138-140 A3 --- ref ? Reference for recombination line
results if cited from another source (6)
142 A1 --- Note [ N] Source comments, N indicates that
section 4 of Caswell and Haynes (1987)
contains additional information or
discussion for this source
145-152 A8 --- Opt Optical counterpart (7)
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Note (1): Coordinates are the position of peak 5GHz continuum intensity
from Haynes et al. (1979AuJPA..48....1H 1979AuJPA..48....1H, Cat. VIII/20).
Note (2): Angular sizes quoted for small diameter sources are widths to
half maximum intensity of the equivalent deconvolved Gaussian
source. For large irregular sources the quoted sizes are the
average major and minor dimensions, and are very approximate.
Note (3): Determined from a Gaussian fit to the observed line profile.
Note (4): Derived from the recombination line LSR velocity assuming the
Schmidt (1965) rotation curve inside the solar circle, a flat
rotation curve (V=250 km/s) outside the solar circle, and 10 kpc
for the distance of the Sun from the Galactic center. Sources
in the first or fourth quadrants with velocities exceeding,
or within 5 km/s of, the terminal velocity as defined by the
Schmidt rotation curve are assigned to the tangent point.
Note (5): For sources with two possible kinematic distance solutions,
d1 contains the near distance and d2 contains the far distance.
For other sources, d1 contains the kinematic distance and d2
is blank.
Note (6): C: Caswell (1972AuJPh..25..443C 1972AuJPh..25..443C),
CC: Caswell and Clark (1975AuJPA.......57C 1975AuJPA.......57C),
Ch: Churchwell et al. (1974A&A....32..283C 1974A&A....32..283C),
CHC: Caswell et al. (1975AuJPh..28..633C 1975AuJPh..28..633C),
HD: Huchtmeier and Day (1975A&A....41..153H 1975A&A....41..153H),
S: Shaver at el. (1983MNRAS.204...53S 1983MNRAS.204...53S),
W: Wilson et al. (1970A&A.....6..364W 1970A&A.....6..364W).
Note (7): 'V', or a specific nebula name, denotes the presence of a
visible optical counterpart, and 'A' indicates the absence
of an optical counterpart.
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Acknowledgements:
H. Andernach and S. Trushkin scanned
the published data table, made format changes, and provided a copy of
their electronic version to ADC.
References:
Caswell, J. L. 1972, Australian J. Phys., 25, 443.
Caswell, J. L., and Clark, D. H. 1975, Australian J. Phys. Astrophys. Suppl.,
No. 37, 57 =1975AuJPA.......57C 1975AuJPA.......57C
Caswell, J. L., and Haynes, R. F. 1987, Astr. Ap., 171, 261
=1987A&A...171..261C 1987A&A...171..261C
Caswell, J. L., Haynes, R. F., and Clark, D. H. 1975, Australian J. Phys.,
28, 633 =1975AuJPh..28..633C 1975AuJPh..28..633C
Churchwell, E., Mezger, P. G., and Huchtmeier, W. 1974, Astr. Ap., 32, 283
=1974A&A....32..283C 1974A&A....32..283C
Gardner, F. F., and Whiteoak, J. B. 1984, M.N.R.A.S., 210, 23
=1984MNRAS.210...23G 1984MNRAS.210...23G
Haynes, R. F., Caswell, J. L., and Simons, L. W. J. 1978, Australian J. Phys.
Astrophys. Suppl., No. 45, 1 =1978AuJPA..45....1H 1978AuJPA..45....1H
Haynes, R. F., Caswell, J. L., and Simons, L. W. J. 1979, Australian J. Phys.
Astrophys. Suppl., No. 48, 1 =1979AuJPA..48....1H 1979AuJPA..48....1H
Huchtmeier, W. K. and Day, G. A. 1975, Astr. Ap., 41, 153
=1975A&A....41..153H 1975A&A....41..153H
Schmidt, M. 1965, in Galactic Structure, eds. A. Blauuw, M. Schmidt, Univ.
Chicago Press, p. 513 =1965QB819.B55...... 1965QB819.B55......
Shaver, P. A., McGee, R. X., Newton, L. M., Danks, A. C., and Pottasch, S. R.
1983, M.N.R.A.S., 204, 53 =1983MNRAS.204...53S 1983MNRAS.204...53S
Whiteoak, J. B., and Gardner, F F. 1974, Astr. Ap., 37, 389
=1974A&A....37..389W 1974A&A....37..389W
Wilson, T. L., Mezger, P. G., Gardner, F. F., Milne, D. K. 1970, Astr. Ap.,
6, 364 =1970A&A.....6..364W 1970A&A.....6..364W
(End) Nils Odegard [SSDOO/ADC] 01-Aug-1999