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J/A+A/324/877    HI properties of spiral and irregular galaxies (Broeils+, 1997)

Short 21-cm WSRT observations of spiral and irregular galaxies. HI properties. Broeils A.H., Rhee M.-H. <Astron. Astrophys., 324, 877-887 (1997)> =1997A&A...324..877B (SIMBAD/NED BibCode)
ADC_Keywords: Galaxy catalogs ; H I data ; Morphology Keywords: galaxies: fundamental parameters - galaxies: structure - galaxies: kinematics and dynamics - galaxies: spiral - radio lines: galaxies Abstract: We present the analysis of neutral hydrogen properties of 108 galaxies, based on short 21-cm observations with the Westerbork Synthesis Radio Telescope (WSRT). The results of two HI surveys are analysed to investigate the existence of relations between optical and HI properties, like diameters, hydrogen masses and average surface densities. For all galaxies in our sample we find that the HI diameter, defined at a surface density level of 1M/pc2, is larger than the optical diameter, defined at the 25thmag/arcsec2 isophotal level. The Hi-to-optical-diameter ratio does not depend on morphological type or luminosity. The strongest, physically meaningful, correlation for the sample of 108 galaxies is the one between logMHI and logDHI, with a slope of 2. This implies that the HI surface density averaged over the whole HI disc is constant from galaxy to galaxy, independent of luminosity or type. The radial HI surface density profiles are studied using the technique of principal component analysis. We find that about 81% of the variation in the density profiles of galaxies can be explained by two dimensions. The most dominant component can be related to "scale" and the second principal component accounts for the variance in the behaviour of the radial profile in the central parts of galaxies (i.e. "peak or depression") . The third component accounts for 7% of the variation and is most likely responsible for bumps and wiggles in the observed density profiles. Description: The type of HI data analysed in this paper contains more spatial information than provided by single-dish observations, but less than provided by usual synthesis observations. Also the sample size (108 galaxies) lies between those of single-dish and synthesis studies. In this paper we therefore concentrate on properties that are special to these two surveys: radial HI surface density profiles, average surface densities and sizes of hydrogen discs. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 58 108 Properties of the sample galaxies
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 7 A7 --- Name Galaxy name 8 A1 --- n_Name [a] Note on Name (1) 10- 13 A4 --- MType Morphological type 15- 17 I3 kpc DHI HI diameter defined by a surface density of 1M/pc2 19- 20 I2 kpc D25 Optical diameter defined at the 25th mag/arcsec2 isophote and corrected for Galactic and internal extinctions following Tully & Fouque (1985ApJS...58...67T) 22- 23 I2 kpc Reff HI effective radius, enclosing 50% of the HI mass 25- 28 F4.2 10+10Msun MHI Total HI mass 30- 34 F5.2 10+10Msun Mtot Total mass enclosed inside the HI diameter DHI (see text) 36- 39 F4.2 Msun/Lsun MHI/LB HI-mass-to-blue-luminosity ratio (2) 41- 44 F4.2 Msun/Lsun MHI/LH ?=- HI-mass-to-near-infrared-luminosity ratio (3) 46- 49 F4.2 --- MHI/Mtot HI-mass-to-total-mass ratio 51- 54 F4.2 Msun/pc+2 <sigHI> Mean value of the HI surface density, averaged over the whole HI disc (see text) 56- 58 I3 km/s Vmax Maximum rotation velocity
Note (1): a: The heliocentric velocity of DDO 185 in paper I (Broeils & van Woerden, 1994A&AS..107..129B) was mistakenly listed as 373km/s . It should be 140km/s. The adopted distance (and all the distance-dependent parameters) will remain the same, since they are based on membership in the M 101 group. Note (2): The total blue luminosity has been corrected for Galactic and internal extinctions following Tully & Fouque (1985ApJS...58...67T). Note (3): The near-infrared luminosity has been taken from Tormen & Burstein (1995, Cat. J/ApJS/96/123), which has been corrected for Galactic extinction.
History: From electronic version of the journal References: Broeils & van Woerden, Paper I 1994A&AS..107..129B
(End) Patricia Vannier [CDS] 27-Oct-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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