J/ApJS/79/77 Bell Lab. H I Survey - High Velocity Clouds (Stark+ 1992)
The Bell Laboratories H I Survey - High Velocity Cloud Catalog
STARK A.A., GAMMIE C.F., WILSON R.W., BALLY J., LINKE R.A.
<Astrophys. J. Suppl. Ser. 79, 77 (1992)>
=1992ApJS...79...77S 1992ApJS...79...77S (SIMBAD/NED Reference)
ADC_Keywords: H I data - 338; Interstellar medium - 360; Radio sources - 685;
Surveys - 975
Abstract:
The sky north of declination -40 deg. was observed in the 21 cm line
of atomic hydrogen with the FWHM = 2 deg. beam of the 20 foot horn
reflector at AT&T Bell Laboratories, Crawford Hill. The survey
covers a velocity range of 654 km/s centered on the Galactic
standard of rest, with 5.3 km/s wide filters. This survey is
distinguished by its sensitivity to low surface brightness features
(antenna temperature about 50 mK) and relative freedom from sidelobe
contamination. The high-velocity cloud list was extracted and
catalogued automatically from the survey data.
Introduction:
Observations were made as drift scans along even declinations
between -40 deg. and +90 deg. at the epoch (1981) of the
observations. The horn antenna has a FWHM beam size of 2 deg. at 21
cm. The average rms noise of spectra taken at all declinations is
0.017 K in 5.2 km/s wide channels, although in some cases baseline
problems make the survey unreliable at this level.
The clouds catalogued were selected to be those near for which the
velocities, when projected on the galactic plane at each possible
distance, differed from the circular rotation velocities by more
than 40 km/s. The boundaries of the clouds were determined by either
a decrease in emission to near the baseline emission or a steep drop
in antenna temperature.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 132 1312 The catalog of high-velocity clouds
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- num +[1,1313]Running number
8- 13 F6.3 deg RAdeg Right Ascension (1950) of peak emission
18- 24 F7.3 deg DEdeg Declination (1950) of peak emission
29- 35 F7.3 deg pkGLON Galactic longitude of peak emission
40- 46 F7.3 deg pkGLAT Galactic latitude of peak emission
50- 55 F6.2 deg maxGLON Maximum galactic longitude of cloud
60- 65 F6.2 deg minGLON Minimum galactic longitude of cloud
70- 75 F6.2 deg maxGLAT Maximum galactic latitude of cloud
80- 85 F6.2 deg minGLAT Minimum galactic latitude of cloud
90- 95 F6.1 km/s maxvel Maximum velocity of cloud
100-105 F6.1 km/s minvel Minimum velocity of cloud
109-115 F7.2 K.km/s Flux Total flux
120-124 F5.2 K antemp Peak antenna temperature
129-132 I4 --- Ncl Number of points cloud detected
(End) N. G. Roman [NASA/NSSDC/ADC] 1994-08-10