J/ApJ/723/1195 SAGE AGB candidates (Riebel+, 2010)
Infrared period-luminosity relations of evolved variable stars in the Large
Magellanic Cloud.
Riebel D., Meixner M., Fraser O., Srinivasan S., Cook K., Vijh U.
<Astrophys. J., 723, 1195-1209 (2010)>
=2010ApJ...723.1195R 2010ApJ...723.1195R
ADC_Keywords: Cross identifications ; Magellanic Clouds ; Photometry, infrared ;
Stars, giant ; Stars, carbon ; Stars, variable
Keywords: infrared: stars - Magellanic Clouds - stars: AGB and post-AGB -
stars: carbon - stars: variables: general
Abstract:
We combine variability information from the MAssive Compact Halo
Objects survey of the Large Magellanic Cloud with infrared photometry
from the Spitzer Space Telescope Surveying the Agents of a Galaxy's
Evolution survey to create a data set of ∼30000 variable red sources.
We photometrically classify these sources as being on the first ascent
of the red giant branch, or as being in one of three stages along the
asymptotic giant branch (AGB): oxygen-rich, carbon-rich, or highly
reddened with indeterminate chemistry ("extreme" AGB candidates). We
present linear period-luminosity (P-L) relationships for these sources
using eight separate infrared bands (J, H, Ks, 3.6, 4.5, 5.8, 8.0, and
24um) as proxies for the luminosity. We find that the wavelength
dependence of the slope of the P-L relationship is different for
different photometrically determined classes of AGB stars. Stars
photometrically classified as O-rich show the least variation of slope
with wavelength, while dust enshrouded extreme AGB stars show a
pronounced trend toward steeper slopes with increasing wavelength. We
find that O-rich AGB stars pulsating in the fundamental mode obey a
period-magnitude relation with a slope of -3.41±0.04 when magnitude
is measured in the 3.6um band, in contrast to C-rich AGB stars, which
obey a relation of slope -3.77±0.05.
Description:
We extract a list of 32744 sources from Fraser et al.'s (2008, Cat.
J/AJ/136/1242) catalog of evolved long-period variables (LPVs) in the
LMC with a counterpart in the SAGE mosaic photometry archive. We use a
matching radius of 2", and keep only the closest SAGE source to a
given MACHO source. We are left with a final data set of 30747
evolved stars with well-defined MACHO periods and high quality near IR
photometry from Two Micron All Sky Survey (2MASS) and SAGE.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 165 30747 Source list of AGB candidates
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See also:
II/305 : SAGE LMC and SMC IRAC Source Catalog (IPAC 2009)
II/247 : Variable Stars in the Large Magellanic Clouds (MACHO, 2001)
J/A+A/537/A105 : Modelisation of AGB stars in the LMC (Gullieuszik+, 2012)
J/A+A/530/A90 : Post-AGB population of LMC (van Aarle+, 2011)
J/MNRAS/411/1597 : LMC point source classification in SAGE-Spec (Woods+, 2011)
J/A+A/506/1277 : Magellanic Cloud C/O stars (Groenewegen+, 2009)
J/AJ/137/4810 : LMC-SAGE AGB star candidates (Srinivasan+, 2009)
J/AJ/137/3139 : LMC SAGE. New variable evolved stars and YSOs (Vijh+, 2009)
J/AJ/138/1003 : IR photometry of massive LMC stars (Bonanos+, 2009)
J/AJ/136/1242 : LMC long-period variables from MACHO (Fraser+, 2008)
J/A+A/480/379 : Abundances of 59 red giants in LMC (Pompeia+, 2008)
J/AJ/122/1844 : MSX and 2MASS cross-correlation in LMC (Egan+, 2001)
J/AJ/99/784 : IR photometry of LMC long-period variables (Hughes+ 1990)
J/ApJ/348/98 : LMC AGB stars IRAS fluxes (Reid+ 1990)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- --- [SSTISAGEMA]
12- 30 A19 --- SSTISAGEMA SAGE IRAC designation (JHHMMSS.ss+DDMMSS.s)
32- 43 A12 --- MACHO MACHO (field.tile.sequence) identifier
45- 52 I8 --- 2MASS ? 2MASS identifier
54 A1 --- Cl [CORX] Photometric classification (C-rich,
O-rich, RGB or eXtreme AGB) (1)
56- 60 F5.3 mag Amp Variability amplitude from MACHO lightcurve
62- 69 F8.3 d VPer Variability period derived from MACHO
lightcurve
71- 75 F5.2 mag Jmag ?=99 2MASS J band magnitude
77- 81 F5.2 mag e_Jmag ?=99 The 1σ error in Jmag
83- 87 F5.2 mag Hmag ?=99 2MASS H band magnitude
89- 93 F5.2 mag e_Hmag ?=99 The 1σ error in Hmag
95- 99 F5.2 mag Ksmag ?=99 2MASS Ks band magnitude
101-105 F5.2 mag e_Ksmag ?=99 The 1σ error in Ksmag
107-111 F5.2 mag [3.6] ?=99 Spitzer/IRAC 3.6 micron band magnitude
113-117 F5.2 mag e_[3.6] ?=99 The 1σ error in [3.6]
119-123 F5.2 mag [4.5] ?=99 Spitzer/IRAC 4.5 micron band magnitude
125-129 F5.2 mag e_[4.5] ?=99 The 1σ error in [4.5]
131-135 F5.2 mag [5.8] ?=99 Spitzer/IRAC 5.8 micron band magnitude
137-141 F5.2 mag e_[5.8] ?=99 The 1σ error in [5.8]
143-147 F5.2 mag [8.0] ?=99 Spitzer/IRAC 8.0 micron band magnitude
149-153 F5.2 mag e_[8.0] ?=99 The 1σ error in [8.0]
155-159 F5.2 mag [24] ?=99 Spitzer/MIPS 24 micron band magnitude
161-165 F5.2 mag e_[24] ?=99 The 1σ error in [24]
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Note (1): Extreme AGB stars are defined using their position in the [3.6] versus
J-[3.6] CMD: J-[3.6]>3.1 and [3.6]<10.5 or the IRAC [8.0] versus
[8.0]-[3.6] CMD if a source lacks a valid J-band magnitude. These
sources are thought to be highly evolved AGB stars, enshrouded by
thick circumstellar dust shells with high rates of mass loss.
See section 2.2 for further classification details.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 25-Jul-2012