ACDS V10.0 - Fri Nov 17 19:02:44 CET 2023
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Detailed Description of II/125 :
IRAS catalogue of Point Sources, Version 2.0 (IPAC 1986)
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Note : this is the description file of the original catalog.
This HTML page corresponds well to the original description, but some minor
changes in the format may have been introduced in the FITS output
files in order to allow for arithmetic operations on quantities
such as coordinates and times. h:m:s and d:m:s units are normally
converted into degrees, and YYYY-MM-DD into julian days.
Similarly, some slight changes may have been introduced in the
units; the value given in the HTML files supersedes the value indicated in the ReadMe
file for this catalogue.
II/125 IRAS catalogue of Point Sources, Version 2.0 (IPAC 1986)
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IRAS Catalog of Point Sources, Version 2.0
Joint IRAS Science W.G.
<IPAC (1986)>
=1988IRASP.C......0J
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ADC_Keywords: Photometry, infrared ; Infrared sources ; Surveys
Mission_Name: IRAS
Description:
This is a catalog of some 250,000 well-confirmed infrared point
sources observed by the Infrared Astronomical Satellite, i.e., sources
with angular extents less than approximately 0.5, 0.5, 1.0, and 2.0
arcmin in the in-scan direction at 12, 25, 60, and 100 microns,
respectively. Positions, flux densities, uncertainties, associations
with known astronomical objects and various cautionary flags are given
for each object. While two other complementary data sets - the Working
Survey Data Base and a file of rejected sources - give information
about point-like sources, the information available in the Point
Source Catalog should satisfy almost all users. Away from confused
regions of the sky, the survey is complete to about 0.4, 0.5, 0.6, and
1.0 Jy at 12, 25, 60, and 100 microns. Typical position uncertainties
are about 2 to 6 arcseconds in-scan and about 8 to 16 arcseconds
cross-scan. The processing steps applied to detect and confirm point
sources, and the positional and photometric error analyses are
described in the IRAS Catalogs and Atlases Explanatory Supplement; the
catalog format is described in Chapter X. The sources appear in order
of increasing (1950.0) right ascension.
The included script "tofits.sh" should generate the FITS version of the
tables on Unix platforms.
References:
IRAS Catalogs and Atlases Explanatory Supplement, 1988, ed. Beichman C.,
Neugebauer G., Habing H.J., Clegg P.E., and Chester T.J.
(Washington, DC: GPO), NASA RP-1190, vol 1
See also:
II/126 : IRAS Serendipitous Survey Catalog
II/156 : IRAS Faint Source Catalog, |b| > 10, Version 2.0
II/274 : IRAS Point Source Reject Catalog
VII/91 : IRAS Asteroid and Comet Survey (1986)
II/190 : IRAS Minor Planet Survey data base (Tedesco, 1992)
III/197 : IRAS Low Resolution Spectra (LRS) (1987)
III/170 : IRAS Point Source Identifications (MacConnell, 1993)
VII/73 : IRAS Small Scale Structure Catalog
VII/113 : Catalogued Galaxies and QSOs observed in IRAS Survey,
Version 2 (IPAC 1989)
II/174 : IRAS 2Jy Redshift Survey Data File
J/A+AS/100/473 : IRAS pointed observations data (Assendorp+, 1993)
J/AJ/109/2318 : Extragalactic IRAS Sources (Condon+ 1995)
J/A+AS/99/31 : Identification of C stars in IRAS (Guglielmo+ 1993)
J/A+AS/113/51 : Catalogue of associations IRAS and S stars (Chen+, 1995)
J/ApJ/411/188 : Classification of bright IRAS variables (Allen+ 1993)
J/A+AS/80/149 : CO observations of IRAS Sources (Wouterloot+ 1989)
J/A+AS/98/589 : H2O, OH, CH3OH and CO obs. of IRAS Sources (Wouterloot+ 1993)
J/A+AS/93/121 : CO emission from a sample of IRAS sources (Nyman+ 1992)
J/A+AS/90/327 : 1612MHz OH survey of IRAS point sources
(te Lintel Hekkert+ 1991)
II/184 : Catalog of Infrared observations, 3rd Edition (Gezari+ 1993)
File Summary:
FileName Lrecl Records Explanations
× 80 . This file
× ReadMe 80 . This file
× psc.txt 79 1091 CD-ROM Documentation
× SIMPLE.fih 81 44 FITS header
× main.dat 157 245889 IRAS Point Sources
× main.fih 80 294 associated FITS header
× assoc.dat 58 142228 Associations
× assoc.fih 80 66 associated FITS header
× meaning.txt 80 235 Details of association catalogues
× tofits.sh 80 74 Unix shell to generate FITS (1)
(1) This small script should run on any Unix platform. To generate the FITS
version of the tables, execute
tofits main > main.fits (for the main table)
tofits assoc > assoc.fits (for the association file)
Byte-by-byte Description of file: main.dat
Bytes Format Units Label Explanations
1- 11 A11 --- IRAS IRAS source name
12- 13 I2 h RAh Hours RA, equinox 1950.0, epoch 1983.5
14- 15 I2 min RAm Minutes RA, equinox 1950.0, epoch 1983.5
16- 18 I3 ds RAds Seconds RA, equinox 1950.0, epoch 1983.5
19 A1 --- DE- Sign Dec, equinox 1950.0, epoch 1983.5
20- 21 I2 deg DEd Degrees Dec, equinox 1950.0, epoch 1983.5
22- 23 I2 arcmin DEm Minutes Dec, equinox 1950.0, epoch 1983.5
24- 25 I2 arcsec DEs Seconds Dec, equinox 1950.0, epoch 1983.5
26- 28 I3 arcsec Major Uncertainty ellipse major axis
29- 31 I3 arcsec Minor Uncertainty ellipse minor axis
32- 34 I3 deg PosAng Uncertainty ellipse position angle (1)
35- 36 I2 --- NHcon Number of times observed
37- 45 E9.3 Jy Fnu_12 Average non-color corrected flux density,
12um (5)
46- 54 E9.3 Jy Fnu_25 Average non-color corrected flux density,
25um (5)
55- 63 E9.3 Jy Fnu_60 Average non-color corrected flux density,
60um (5)
64- 72 E9.3 Jy Fnu_100 Average non-color corrected flux density,
100um (5)
73 I1 --- qFnu12 [1,3] Flux density quality, 12um (3)
74 I1 --- qFnu25 [1,3] Flux density quality, 25um (3)
75 I1 --- qFnu60 [1,3] Flux density quality, 60um (3)
76 I1 --- qFnu100 [1,3] Flux density quality, 100um (3)
77- 78 I2 --- NLRS Number of significant LRS spectra (4)
79- 80 A2 --- LRSChar Characterization of averaged LRS spectrum (4)
81- 83 I3 % eFnu12 Percent relative flux den. uncertainty, 12um
84- 86 I3 % eFnu25 Percent relative flux den. uncertainty, 25um
87- 89 I3 % eFnu60 Percent relative flux den. uncertainty, 60um
90- 92 I3 % eFnu100 Percent relative flux den. uncertainty, 100um
93- 97 I5 --- TSNR_12 10x minimum signal-to-noise ratio, 12um
98-102 I5 --- TSNR_25 10x minimum signal-to-noise ratio, 25um
103-107 I5 --- TSNR_60 10x minimum signal-to-noise ratio, 60um
108-112 I5 --- TSNR_100 10x minimum signal-to-noise ratio, 100um
113 A1 --- CC_12 Point source correlation coeff., 12um (8)
114 A1 --- CC_25 Point source correlation coeff., 25um (8)
115 A1 --- CC_60 Point source correlation coeff., 60um (8)
116 A1 --- CC_100 Point source correlation coeff., 100um (8)
117-118 I2 % Var Percent likelihood of variability
119 A1 --- Disc Discrepant fluxes flag, 1 per band,
hex encoded (6)
120 A1 --- Confuse Confusion flags, 1 per band, hex encoded (6)
121 I1 --- PNearH Number of nearby hours-confirmed point sources
122 I1 --- PNearW Number of nearby weeks-confirmed point sources
123 I1 --- SES1_12 Nearby seconds-confirmed small ext., 12um (7)
124 I1 --- SES1_25 Nearby seconds-confirmed small ext., 25um (7)
125 I1 --- SES1_60 Nearby seconds-confirmed small ext., 60um (7)
126 I1 --- SES1_100 Nearby seconds-confirmed small ext., 100um (7)
127 I1 --- SES2_12 Nearby weeks-confirmed small ext., 12um (7)
128 I1 --- SES2_25 Nearby weeks-confirmed small ext., 25um (7)
129 I1 --- SES2_60 Nearby weeks-confirmed small ext., 60um (7)
130 I1 --- SES2_100 Nearby weeks-confirmed small ext., 100um (7)
131 A1 --- HSDFlag High source density bin flag, hex encoded (6)
132 I1 --- Cirr1 Number of nearby 100 micron only WSDB sources
133 I1 --- Cirr2 100 micron sky brightness ratio to flux den.
(2)
134-136 I3 MJy/sr Cirr3 Total 100 micron sky surface brightness
137-138 I2 --- NID Number of positional associations
139 I1 --- IDType [1,4] Type of association (9)
140-141 I2 --- MHcon ? Possible number of HCONs
142-145 I4 10-3 FCor_12 ? Flux correction factor applied (5)
146-149 I4 10-3 FCor_25 ? Flux correction factor applied (5)
150-153 I4 10-3 FCor_60 ? Flux correction factor applied (5)
154-157 I4 10-3 FCor_100 ? Flux correction factor applied (5)
Note (1): Measured in degrees east of north between the major axis of
the ellipse and the local equatorial meridian.
Note (2): The spatially filtered 100 micron sky brightness to flux
density ratio of point source (see Explanatory Supplement)
Note (3): 3=high quality, 2=moderate quality, 1=upper limit
Note (4): Low Resolution Spectra, see Cat. III/197
Note (5): The flux densities listed in the catalog are average values
computed for the effective wavelengths of the IRAS bands and an
assumed input energy distribution F({nu}){prop.to}1/{nu} (i.e. a
spectral index of -1). See details in the Explanatory Supplement
or at the IRAS archive site at
http://lambda.gsfc.nasa.gov/product/iras/colorcorr.cfm
Note (6): The hexadecimal encoding is the representation of a 4-bit
number with values set to 1=12um, 2=25um, 4=60um, 8=100um. For
instance, the value A=10=8+2 has flags set for 25 and 100um.
Note (7): Values of SES1 greater than 1 should caution the user that
significant extended structure may exist in the region and that
the source in question may be a point-source like piece of a
complex field. SES2 values greater than 0 means that the point
source flux measurement should be treated with caution as the
source in question may, in fact, be extended; the flux quoted
in the catalog of small extended sources (Cat. VII/73) may
provide a better value for the source.
Note (8): from section V.C.4 of the Explanation:
the point source correlation coefficient can have values in the range
87-100%, coded as alphabetic characters with A=100, B=99 .. N=87
Note (9): Type of association with:
1 = extragalactic catalog ;
2 = stellar catalog ;
3 = other catalogs ;
4 = multiple types of catalogs.
Byte-by-byte Description of file: assoc.dat
Bytes Format Units Label Explanations
1- 11 A11 --- IRAS IRAS source name
12- 17 I6 --- RecNo Main data table record number for IRAS source
19- 20 I2 --- CatNum Catalog number (1)
21- 35 A15 --- Source Source identification
36- 40 A5 --- Type Source type or spectral class
41- 43 I3 arcsec Radius Radius vector from IRAS source to association
44- 46 I3 deg Pos Position angle (E of N), IRAS source to object
47- 50 I4 --- Field1 Object data field 1, catalog dependent
51- 54 I4 --- Field2 Object data field 2, catalog dependent
55- 58 I4 --- Field3 Object data field 3, catalog dependent
Note (1): See Table X.B.4 in the "IRAS Catalogs and Atlases Explanatory
Supplement" also included in the "meaning.txt" file.
Historical Notes:
The catalogue is also available on the CD-ROM
"Selected Astronomical Catalogues", Volume 1, 1992,
Astronomical Data Center, NASA, directory photom/iraspsc
* 10-Jun-2004: in file "assoc.dat", record#133500, a control-character
(in Field 2 representing a spectral type) was replaced.
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(End) [CDS] 29-Jan-1994