J/A+A/401/873 The SMC in the Far Infrared (Wilke+, 2003)
The Small Magellanic Cloud in the far infrared.
I. ISO's 170µm map and revisit of the IRAS 12-100µm data.
Wilke K., Stickel M., Haas M., Herbstmeier U., Klaas U., Lemke D.
<Astron. Astrophys. 401, 873 (2003)>
=2003A&A...401..873W 2003A&A...401..873W
ADC_Keywords: Galaxies, nearby; Galaxies, IR; Interstellar medium; H II regions
Mission_Name: ISO
Keywords: Galaxies: Magellanic Clouds - ISM: general - ISM: dust, extinction
Abstract:
The ISOPHOT experiment onboard the ISO satellite generated a complete
view of the Small Magellanic Cloud (SMC) at 170µm with 1.5arcmin
resolution. The map is analysed using an automated photometry program
enabling accurate photometric characterization of the far infrared
(FIR) emitting regions.
In this paper, the sources detected at 170µm are compared with
those obtainable from the IRAS satellite data. For this purpose, the
12µm, 25µm, 60µm, and 100µm IRAS high resolution
(HiRes) maps of the SMC are re-examined using the same method. In
contrast to former studies, this provides an all-band ISO/IRAS source
catalog which is no longer based on eyeball classification, but relies
on an algorithm which is capable of automated, repeatable photometry,
even for irregular sources. In the mid infrared IRAS bands numerous
bright FIR emitting regions in the SMC are detected and classified:
73 sources are found at 12µm, 135 at 25µm (most of them with
Fν<1.0Jy). All three FIR bands at 170µm, 100µm, and
60µm reproduce the overall morphological structure of the SMC
similarly well, in contrast to the 12µm and 25µm maps which
only contain a limited number of extended sources and do not trace the
main body of the SMC. 243 sources are detected in the ISO 170µm
map, 155 of them with Fν≥2.0Jy. Comparable numbers are found for
the two FIR IRAS maps at 60µm (384) and 100µm (338) with
fluxes up to 450Jy. 70 of the 243 170µm sources are assigned a
general SED type (cold , warm , i.e., <30K, >30K) for the first
time. A comparison with earlier IRAS results suggests that many source
flux densities in those studies have been under- or overestimated
because of non-standardized fitting methods. Many sources with flux
densities up to 40Jy listed in former catalogs cannot be identified
in our data.
Description:
For each of the files (tablea, tableb, ... tablef), one of the five
available IRAS/ISO catalogs (IRAS: 12, 25, 60, 100µm, ISO:
170µm), was taken "master catalog" and cross-correlated with all
other catalogs. If the distance between a source of the master catalog
and a source from one of the other catalogs ("slave catalogs") at a
different wavelength was found to be less than 90" (correlation
length), the two sources were considered identical. The tables contain
the entry numbers of the master catalog (first column) as well as the
corresponding index numbers of the remaining four slave catalogs (the
four rightmost columns, ordered by decreasing wavelengths). More than
one entry in an index number column indicates the presence of two or
more sources within the corresponding correlation radius of 90".
Source coordinates, fluxes and uncertainties have been obtained from
the HIIphot program.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea.dat 194 73 The IRAS 12µm source catalog
tableb.dat 205 135 The IRAS 25µm source catalog
tablec.dat 177 384 The IRAS 60µm source catalog
tabled.dat 165 338 The IRAS 100µm source catalog
tablee.dat 166 243 The ISO 170µm source catalog
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See also:
I/270 : Catalog of Positions of IR Stellar Sources (CPIRSS) (Hindsley+ 1994)
I/125 : IRAS catalogue of Point Sources, Version 2.0 (IPAC 1986)
II/156 : IRAS Faint Source Catalog, |b| > 10, Version 2.0 (Moshir+ 1989)
VI/101 : ISO Observation Log (ISO Team, 2001)
II/181 : IR sources in Magellanic Clouds (Schwering+ 1990)
Byte-by-byte Description of file: tablea.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- N12 Sequence number in IRAS 12µm catalog
5- 6 I2 h RAh Right ascension (J2000)
8- 9 I2 min RAm Right ascension (J2000)
11- 12 I2 s RAs Right ascension (J2000)
14 A1 --- DE- Declination sign (J2000)
15- 16 I2 deg DEd Declination (J2000)
18- 19 I2 arcmin DEm Declination (J2000)
21- 22 I2 arcsec DEs Declination (J2000)
24- 28 F5.1 Jy F12um Source flux density at 12µm
30- 34 F5.1 Jy e_F12um Uncertainty of the source flux density
(1 sigma error)
37- 44 A8 --- N170 ? Cross identification number in
`slave' catalog (170µm ISO) (G1)
46- 53 A8 --- N100 ? cross identification number in
`slave' catalog (100µm IRAS) (G1)
55- 62 A8 --- N60 ? cross identification number in
`slave' catalog (60µm IRAS) (G1)
64- 71 A8 --- N25 ? cross identification number in
`slave' catalog (25µm IRAS) (G1)
73- 75 A3 --- Type [CWQ() ] Source classification (G2)
77- 92 A16 --- Ratio IRAS or ISO 170µm/100µm flux ratio (G3)
94- 96 A3 --- (CW) [(CW) ] Schwering & Israel, 1989,
Cat. II/181 classification (G4)
98-194 A97 --- ID Other cross-identifications (G4)
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Byte-by-byte Description of file: tableb.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- N25 Sequence number in 25µm IRAS catalog
5- 6 I2 h RAh Right ascension (J2000)
8- 9 I2 min RAm Right ascension (J2000)
11- 12 I2 s RAs Right ascension (J2000)
14 A1 --- DE- Declination sign (J2000)
15- 16 I2 deg DEd Declination (J2000)
18- 19 I2 arcmin DEm Declination (J2000)
21- 22 I2 arcsec DEs Declination (J2000)
24- 28 F5.1 Jy F25um Source flux density at 25µm
30- 34 F5.1 Jy e_F25um Uncertainty of the source flux density
(1 sigma error)
37- 44 A8 --- N170 ? Cross identification number in
`slave' catalog (170µm ISO) (G1)
46- 53 A8 --- N100 ? cross identification number in
`slave' catalog (100µm IRAS) (G1)
55- 62 A8 --- N60 ? cross identification number in
`slave' catalog (60µm IRAS) (G1)
64- 71 A8 --- N12 ? cross identification number in
`slave' catalog (12µm IRAS) (G1)
73- 75 A3 --- Type [CWQ() ] Source classification (G2)
77- 92 A16 --- Ratio IRAS or ISO 170µm/100µm flux ratio (G3)
94- 96 A3 --- (CW) [(CW) ] Schwering & Israel, 1989,
Cat. II/181 classification (G4)
98-205 A108 --- ID Other cross-identifications (G5)
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Byte-by-byte Description of file: tablec.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- N60 Sequence number in 60µm IRAS catalog
5- 6 I2 h RAh Right ascension (J2000)
8- 9 I2 min RAm Right ascension (J2000)
11- 12 I2 s RAs Right ascension (J2000)
14 A1 --- DE- Declination sign (J2000)
15- 16 I2 deg DEd Declination (J2000)
18- 19 I2 arcmin DEm Declination (J2000)
21- 22 I2 arcsec DEs Declination (J2000)
24- 28 F5.1 Jy F60um Source flux density at 60µm
30- 34 F5.1 Jy e_F60um Uncertainty of the source flux density
(1 sigma error)
37- 44 A8 --- N170 ? Cross identification number in
`slave' catalog (170µm ISO) (G1)
46- 53 A8 --- N100 ? cross identification number in
`slave' catalog (100µm IRAS) (G1)
55- 62 A8 --- N25 ? cross identification number in
`slave' catalog (25µm IRAS) (G1)
64- 71 A8 --- N12 ? cross identification number in
`slave' catalog (12µm IRAS) (G1)
73- 75 A3 --- Type [CWQ() ] Source classification (G2)
77- 92 A16 --- Ratio IRAS or ISO 170µm/100µm flux ratio (G3)
94- 96 A3 --- (CW) [(CW) ] Schwering & Israel, 1989,
Cat. II/181 classification (G4)
98-177 A80 --- ID Other cross-identifications (G5)
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Byte-by-byte Description of file: tabled.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- N100 Sequence number in 100µm IRAS catalog
5- 6 I2 h RAh Right ascension (J2000)
8- 9 I2 min RAm Right ascension (J2000)
11- 12 I2 s RAs Right ascension (J2000)
14 A1 --- DE- Declination sign (J2000)
15- 16 I2 deg DEd Declination (J2000)
18- 19 I2 arcmin DEm Declination (J2000)
21- 22 I2 arcsec DEs Declination (J2000)
24- 28 F5.1 Jy F100um Source flux density at 100µm
30- 34 F5.1 Jy e_F100um Uncertainty of the source flux density
(1 sigma error)
37- 44 A8 --- N170 ? Cross identification number in
`slave' catalog (170µm ISO) (G1)
46- 53 A8 --- N60 ? cross identification number in
`slave' catalog (60µm IRAS) (G1)
55- 62 A8 --- N25 ? cross identification number in
`slave' catalog (25µm IRAS) (G1)
64- 71 A8 --- N12 ? cross identification number in
`slave' catalog (12µm IRAS) (G1)
73- 75 A3 --- Type [CWQ() ] Source classification (G2)
77- 92 A16 --- Ratio IRAS or ISO 170µm/100µm flux ratio (G3)
94- 96 A3 --- (CW) [(CW) ] Schwering & Israel, 1989,
Cat. II/181 classification (G4)
98-165 A68 --- ID Other cross-identifications (G5)
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Byte-by-byte Description of file: tablee.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- N170 Sequence number in 170µm ISO catalog
5- 6 I2 h RAh Right ascension (J2000)
8- 9 I2 min RAm Right ascension (J2000)
11- 12 I2 s RAs Right ascension (J2000)
14 A1 --- DE- Declination sign (J2000)
15- 16 I2 deg DEd Declination (J2000)
18- 19 I2 arcmin DEm Declination (J2000)
21- 22 I2 arcsec DEs Declination (J2000)
24- 28 F5.1 Jy F170um Source flux density at 170µm
30- 34 F5.1 Jy e_F170um Uncertainty of the source flux density
(1 sigma error)
37- 44 A8 --- N100 ? Cross identification number in
`slave' catalog (100µm IRAS) (G1)
46- 53 A8 --- N60 ? cross identification number in
`slave' catalog (60µm IRAS) (G1)
55- 62 A8 --- N25 ? cross identification number in
`slave' catalog (25µm IRAS) (G1)
64- 71 A8 --- N12 ? cross identification number in
`slave' catalog (12µm IRAS) (G1)
73- 75 A3 --- Type [CWQ() ] Source classification (G2)
77- 92 A16 --- Ratio IRAS or ISO 170µm/100µm flux ratio (G3)
94- 96 A3 --- (CW) [(CW) ] Schwering & Israel, 1989,
Cat. II/181 classification (G4)
98-166 A69 --- ID Other cross-identifications (G5)
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Global notes:
Note (G1): More than one entry in an index number column indicates the
presence of two sources within the corresponding correlation radius of 90".
Note (G2): Classification:
C: cold source when the color temperatures (assuming a modified black
body with an emissivity of β=2) derived from both, the
170µm/1004mu+m and the 100µm/60µm ratios, are TBB<30K
W: warm source when TBB>30K is obtained in both cases
(C): denotes sources where a classification as "C" remains uncertain
due to missing 60µm and/or 100µm data points.
Q: questionable, when the precise shape of the SED cannot be derived
due to source confusion.
Note (G3): 170µm/100µm ratio:
FISO(170/100) = ISO F(170µm)/F(100µm) flux ratio
FIRAS(170/100) = IRAS F(170µm)/F(100µm) flux ratio
Note (G4): Classification made with the source catalogs given by
Schwering & Israel, 1989, Cat. II/181:
(C): cold source
(W): warm source
Note (G5): Identifications:
X(HFP2/NNN) = [HFP2000] NNN in Simbad
X(SHP2/SMC30) = [SHP2000] SMC 30 in Simbad
X(YIT2/NN) = [YIT2000] NN in Simbad
MA93 NNNN = [MA93] NNNN in Simbad
AM77 NN = [AM77] NN in Simbad
BS95 NNN = [BS95] NNN in Simbad
FJW97 BHHMM-DDMM = [FJW97] SMC BHHMM-DDMM in Simbad
H86 NNN = [H86] NNN in Simbad
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Acknowledgements: Karsten Wilke
History:
* Some corrections made on 20-Nov-2003:
In tablec.dat:
No 30, IRAS 00403-7347 modified into IRAS 00402-7347
No 86, IRAS 00466-7332 modified into IRAS 00466-7322
No 179, RXJ0055.2-7239 modified into RXJ0055.2-7238
No 267, RXJ-1-3.0-7225 modified into RXJ0103.0-7225
In tabled.dat:
No 42, IRAS 00494-7216 modified into IRAS 00495-7216
No 178, IRAS 01098-7328 modified into 01098-7238
(End) Patricia Bauer [CDS] 03-Apr-2003