J/A+AS/101/153 Galactic H2O masers (Palagi+ 1993)
Classification and statistical properties of galactic H2O masers Palagi F., Cesaroni R., Comoretto G., Felli M., Natale V. <Astron. Astrophys. Suppl. Ser. 101, 153 (1993)> =1993A&AS..101..153P
ADC_Keywords: Masers; Infrared sources Keywords: masers - interstellar medium: general - circumstellar matter - infrared: interstellar continuum - infrared: stars Abstract: The association between galactic H2O masers and IRAS sources from the Point Source Catalog (Cat. II/125) is established for 442 sources out of a list of 505 objects, which includes all the galactic H2O masers north of 30°, known up to 1988. Using a multivariate statistical analysis on the four far-IR fluxes of the associated IRAS source, galactic H2O masers are reclassified into two classes: those associated to star forming regions (SFR, 52%) and those associated to late type stars (STAR, 45%). The remaining 3% cannot be included in either class. The present classification is compared with others in the literature. Distances for a large subsample of 1120 masers are derived, using the galactic rotation curve for SFR and literature data for STAR.The parameters of the H2O maser emission (e.g. integrated flux, luminosity, variability), collected in a homogeneous way in the Arcetri H2O atlas (Comoretto et al. 1990A&AS...84..179C), and those of the associated IRAS sources (e.g. flux density, luminosity, colours) are used to investigate, in a statistical way, the properties of the STAR and SFR classes. In particular, we investigate the spatial distribution of masers both in the galactic plane and perpendicular to it. We also compare the H2O and IRAS luminosities, finding a good correlation. Moreover, we find that high luminosity sources show low colour temperatures and vice versa. The spectral profile and variability are then investigated by different means. Finally, the luminosity function for each maser class is derived. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 111 505 H2O Masers and IRAS-PSC sources. table5.dat 108 505 Parameters of H2O Masers.
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
3- 5 I3 --- Seq [1/505]+ Sequential number <[PCC93] NNN> in Simbad 8- 9 I2 h RAh Right Ascension of H2O observations (B1950) 11- 12 I2 min RAm Right Ascension (minutes) 14- 17 F4.1 s RAs Right Ascension (seconds) 20 A1 --- DE- Declination Sign 21- 22 I2 deg DEd Declination of H2O observations (B1950) 24- 25 I2 arcmin DEm Right Ascension (arcminutes) 27- 30 F4.1 arcsec DEs Right Ascension (arcseconds) 35- 48 A14 --- Name Name of the maser source 53- 56 A4 --- Class Class to which the source is assigned (1) 58- 64 F7.3 deg GLON Galactic longitude 65- 71 F7.3 deg GLAT Galactic latitude 74- 84 A11 --- IRAS IRAS name 90- 95 F6.1 arcsec dRA ? R.A. offset H2O - IRAS 99-104 F6.1 arcsec dDE ? Dec. offset H2O - IRAS 111 A1 --- Rem [123mbs-] IRAS associations (2)
Note (1): classes as follows: SFR = star-forming region STAR = stellar source STRN = strange UNKN = unknown Note (2): This column indicates the number of IRAS sources associated with the maser if the column contains a digit (1, 2, or 3); otherwise: m = 2 or more masers are associated with the same IRAS sources; 'm' indicates the selected maser b = 2 or more masers are associated with the same IRAS sources; 'b' indicates it's not the selected maser s = not surveyed - = extended IR source, or lack of association.
Byte-by-byte Description of file: table5.dat
Bytes Format Units Label Explanations
3- 5 I3 --- Seq [1/505]+ Sequential number 8 A1 --- l_F.H2O [<*] Flag: < (upper limit) or * (single component source) 11- 18 F8.1 Jy F.H2O Flux density of the strongest component in the spectrum 21- 28 F8.1 Jy Fi.H2O ? Integrated H2O flux 30- 35 F6.1 km/s Vpeak ? Velocity of the peak 37- 42 F6.1 km/s Vlow ? Velocity of the lowest component 44- 49 F6.1 km/s Vhigh ? Velocity of the highest component 52- 57 F6.3 km/s FWHM ? FWHM of the strongest component 60- 64 F5.2 --- dV ? Offset of the strongest component from the mean velocity, normalized to the emission interval. 69- 76 E8.3 W/m2 FIR ? Far-IR flux integrated over the four IRAS bands 80- 84 F5.2 kpc Dist ? Distance of source 90- 96 E7.2 Lsun Lmaser ? Maser luminosity 102-108 E7.2 Lsun L.FIR ? Far-IR luminosity
(End) [CDS] 12-Mar-1993
|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|