J/AJ/122/1844 MSX and 2MASS cross-correlation in LMC (Egan+, 2001)
MSX, 2MASS, and the Large Magellanic Cloud:
a combined near- and mid-infrared view.
Egan M.P., van Dyk S.D., Price S.D.
<Astron. J. 122, 1844 (2001)>
=2001AJ....122.1844E 2001AJ....122.1844E
ADC_Keywords: Magellanic Clouds ; Surveys ; Photometry, infrared
Keywords: catalogs - galaxies: dwarf - galaxies: stellar content -
infrared radiation - Local Group - Magellanic Clouds -
stars: AGB and post-AGB - stars: carbon - stars: late-type -
supergiants - surveys
Abstract:
The Large Magellanic Cloud (LMC) has been observed by the Midcourse
Space Experiment (MSX) in the mid-infrared and the Two Micron All Sky
Survey (2MASS) in the near-infrared. We have performed a
cross-correlation of the 1806 MSX catalog sources and nearly 1.4
million 2MASS catalogued point and extended sources and find 1664
matches. Using the available color information, we identify a number
of stellar populations and nebulae, including main-sequence stars,
giant stars, red supergiants, carbon- and oxygen-rich asymptotic giant
branch (AGB) stars, planetary nebulae, H II regions, and other dusty
objects likely associated with early-type stars. A total of 731 of
these sources have no previous identification. We compile a listing of
all objects, which includes photometry and astrometry. The 8.3µm
MSX sensitivity is the limiting factor for object detection: only the
brighter red objects, specifically the red supergiants, AGB stars,
planetary nebulae, and H II regions, are detected in the LMC. The
remaining objects are likely in the Galactic foreground. The spatial
distribution of the infrared LMC sources may contribute to
understanding stellar formation and evolution and the overall galactic
evolution. We demonstrate that a combined mid- and near-infrared
photometric baseline provides a powerful means of identifying new
objects in the LMC for future ground-based and space-based follow-up
observations.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 87 1488 MSX sources in common with the 2MASS 2IDR
table3.dat 88 176 MSX sources in common with the 2MASS unreleased
regions
table4.dat 78 142 MSX sources without 2MASS point source matches
--------------------------------------------------------------------------------
See also:
B/2mass : The 2MASS database (IPAC/UMass, 2000)
V/98 : MSX Infrared Astrometric Catalog (Egan+ 1996)
V/107 : MSX5C Infrared Point Source Catalog (Egan+ 1999)
Table 1: SPIRIT III spectral bands
--------------------------------------------------------------------------------
Band Active Isophotal 50% Peak Isophotal Abs. Photom LMC Survey
columns lambda (um) intensity BW (um) accuracy (%) sens. (Jy)
--------------------------------------------------------------------------------
A 8 8.28 6.8 -10.8 3.36 5 0.045
B1 2 4.29 4.22- 4.36 0.104 9 10.
B2 2 4.35 4.24- 4.45 0.179 9 6.
C 4 12.13 11.1 -13.2 1.72 3 0.6
D 4 14.65 13.5 -15.9 2.23 4 0.5
E 2 21.34 18.2 -25.1 6.24 6 1.1
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- MSX The MSX number (G1)
6- 12 F7.4 deg RAdeg Right Ascension in decimal degrees (J2000)
14- 21 F8.4 deg DEdeg Declination in decimal degrees (J2000)
23- 27 F5.2 mag Jmag ? The J band magnitude
29- 33 F5.2 mag Hmag ? The H band magnitude
35- 39 F5.2 mag Kmag ? The Ks band magnitude
41- 45 F5.2 mag Amag The MSX A-band (8.3µm) magnitude
47- 53 A7 --- IRType The IR type
55- 67 A13 --- SType The SIMBAD type
69- 89 A21 --- SName The SIMBAD name
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- MSX The MSX number (G1)
6- 12 F7.4 deg RAdeg Right Ascension in decimal degrees (J2000)
14- 21 F8.4 deg DEdeg Declination in decimal degrees (J2000)
23- 27 F5.3 mag Amag The MSX A-band (8.28µm) magnitude
29- 33 F5.3 mag Cmag ? The MSX C-band (12.13µm) magnitude
35- 39 F5.3 mag Dmag ? The MSX D-band (14.65µm) magnitude
41- 46 F6.3 mag Emag ? The MSX E-band (21.34µm) magnitude
48- 52 A5 --- SType The SIMBAD type
54- 71 A18 --- SName The SIMBAD name
73 I1 --- Note1 Number of MSX scan legs in which the source
was detected (1)
75 I1 --- Note2 ? Source appearance code in MSX A-band
coadded image (2)
77 I1 --- Note3 ? Source appearance code in the 2MASS
images (3)
--------------------------------------------------------------------------------
Note (1): This is a possible measure of the source's reliability.
Note (2): Note on source appearance in MSX A-band coadded image:
NULL = point source in MSX image;
2 = multiple/blended source at position;
3 = extended emission source at position;
4 = very low SNR source, possibly not real; and,
5 = no apparent emission.
Note (3): Note on source appearance in the 2MASS images:
NULL = source not seen in 2MASS images;
2 = extended 2MASS emission;
3 = very bright (saturated) 2MASS star;
4 = possible positional mismatch; and,
5 = possible faint emission at source position in 2MASS images.
--------------------------------------------------------------------------------
Global notes:
Note (G1): The MSX number is the original number of the record in the
table "lmc.dat" in MSX (Cat. V/107) catalog, MSX LMC NNNN in Simbad.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 29-Jan-2002