J/ApJ/856/170 Tracers of stellar mass-loss. II. (Gonzalez-Lopezlira, 2018)
Tracers of stellar mass-loss.
II. Mid-IR colors and surface brightness fluctuations.
Gonzalez-Lopezlira R.A.
<Astrophys. J., 856, 170-170 (2018)>
=2018ApJ...856..170G 2018ApJ...856..170G (SIMBAD/NED BibCode)
ADC_Keywords: Models, evolutionary; Stars, ages; Magellanic Clouds;
Photometry, infrared; Clusters, open
Keywords: galaxies: stellar content; infrared: stars; Magellanic Clouds;
stars: AGB and post-AGB; stars: evolution; stars: mass-loss
Abstract:
I present integrated colors and surface brightness fluctuation
magnitudes in the mid-infrared (IR), derived from stellar population
synthesis models that include the effects of the dusty envelopes
around thermally pulsing asymptotic giant branch (TP-AGB) stars. The
models are based on the Bruzual & Charlot CB* isochrones; they are
single-burst, range in age from a few Myr to 14Gyr, and comprise
metallicities between Z=0.0001 and Z=0.04. I compare these models to
mid-IR data of AGB stars and star clusters in the Magellanic Clouds,
and study the effects of varying self-consistently the mass-loss rate,
the stellar parameters, and the output spectra of the stars plus their
dusty envelopes. I find that models with a higher than fiducial
mass-loss rate are needed to fit the mid-IR colors of "extreme" single
AGB stars in the Large Magellanic Cloud. Surface brightness
fluctuation magnitudes are quite sensitive to metallicity for 4.5µm
and longer wavelengths at all stellar population ages, and powerful
diagnostics of mass-loss rate in the TP-AGB for intermediate-age
populations, between 100Myr and 2-3Gyr.
Description:
For comparison with the models, I use data from the Spitzer Space
Telescope surveys of the LMC and SMC: SAGE (Meixner+ 2006, J/AJ/132/2268 ;
Meixner 2008PASA...25..149M 2008PASA...25..149M) and SAGE-SMC (Gordon+ 2011AJ....142..102G 2011AJ....142..102G),
respectively.
I have measured in the SAGE mosaics the integrated magnitudes of the
LMC and SMC clusters listed in Table 4. See section 3.2 for further details.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 54 532 *IR colors for CB* models with fiducial mass-loss
table3.dat 61 532 *Surface brightness fluctuation (SBF) amplitudes for
CB* models with fiducial mass-loss
table4.dat 79 115 Individual cluster photometry
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Note on table2.dat and table3.dat: The models are based on the
Bruzual & Charlot (2003MNRAS.344.1000B 2003MNRAS.344.1000B) CB* isochrones. The CB* models
are based on the stellar evolution models computed by Bertelli+ (2009,
J/A+A/508/355).
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See also:
III/232 : STELIB -- A library of stellar spectra at R 2000 (Le Borgne+, 2003)
J/A+A/531/A165 : MILES atmospheric parameters (Prugniel+, 2011)
J/MNRAS/403/1213 : Tracers of stellar mass-loss. I. (Gonzalez-Lopezlira+, 2010)
J/AJ/138/1243 : The star formation history of the LMC (Harris+, 2009)
J/A+A/503/913 : Synthetic spectrophotometry for C-rich giants (Aringer+, 2009)
J/AJ/137/4810 : LMC-SAGE AGB star candidates (Srinivasan+, 2009)
J/A+A/484/815 : Scaled solar tracks and isochrones (Bertelli+, 2008)
J/AJ/132/2268 : SAGE calibration stars (Meixner+, 2006)
J/MNRAS/371/703 : MILES library of empirical spectra (Sanchez-Blazquez+, 2006)
J/ApJ/611/270 : Magellanic star clusters IR fluctuations (Gonzalez+, 2004)
J/AJ/127/1531 : Star formation history of SMC (Harris+, 2004)
J/A+A/393/167 : Mean Spectra for upper AGB stars (Lancon+, 2002)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 6 F6.4 --- Z [0.0001/0.04] Metallicity
8- 12 F5.3 --- Y [0.2/0.4] He content
14- 19 F6.3 Gyr Age [0.005/13.5] Single stellar population age
21- 26 F6.3 mag [V-3.6] [-0.7/3.9] V-3.6um color index
28- 33 F6.3 mag [3.6-4.5] [-0.2/0.6] 3.6-4.5um color index
35- 40 F6.3 mag [4.5-5.8] [-0.03/0.7] 4.5-5.8um color index
42- 47 F6.3 mag [5.8-8] [-0.02/0.9] 5.8-8um color index
49- 54 F6.3 mag [8-24] [-0.6/2.2] 8-24um color index
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.4 --- Z [0.0001/0.04] Metallicity
8- 14 F7.3 --- Y [0.2/0.4] He content
16- 21 F6.3 Gyr Age [0.005/13.5] Single stellar population age
23- 29 F7.3 mag barM3.6 [-12/-4] 3.6um surface brightness fluctuation,
absolute magnitude
31- 37 F7.3 mag barM4.5 [-11.9/-4] 4.5um surface brightness
fluctuation, absolute magnitude
39- 45 F7.3 mag barM5.8 [-12/-4.1] 5.8um surface brightness
fluctuation, absolute magnitude
47- 53 F7.3 mag barM8 [-13/-4.1] 8um surface brightness fluctuation,
absolute magnitude
55- 61 F7.3 mag barM24 [-15.3/-3.7] 24um surface brightness
fluctuation, absolute magnitude
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- SC Supercluster (Pre-SWB or SWB I-VII) (1)
9- 16 A8 --- Name Name
18- 20 A3 --- Cloud Magellanic Cloud (LMC or SMC)
22- 26 F5.2 mag 3.6mag [6/13.1]? Integrated 3.6um band magnitude
from SAGE mosaics
28- 31 F4.2 mag e_3.6mag [0.01/0.3]? Uncertainty in 3.6mag
33- 37 F5.2 mag 4.5mag [6/13.2]? Integrated 4.5um band magnitude
from SAGE mosaics
39- 42 F4.2 mag e_4.5mag [0.01/0.3]? Uncertainty in 4.5mag
44- 48 F5.2 mag 5.8mag [5/12]? Integrated 5.8um band magnitude
from SAGE mosaics
50- 53 F4.2 mag e_5.8mag [0.01/0.2]? Uncertainty in 5.8mag
55- 60 F6.3 mag 8.0mag [3.5/12.6]? Integrated 8.0um band magnitude
from SAGE mosaics
62- 66 F5.3 mag e_8.0mag [0.005/0.4]? Uncertainty in 8.0mag
68- 73 F6.3 mag 24mag [-0.7/10]? Integrated 24um band magnitude
from SAGE mosaics
75- 79 F5.3 mag e_24mag [0.004/1]? Uncertainty in 24mag
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Note (1): See Table 5 (excerpt below):
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Super Log Age Z Mass [3.6-4.5]
-cluster (year) (106Msun)
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pre 6.78±0.62 0.010±0.005^c 0.08±0.02 0.19±0.29
I 7.51±0.32 0.010±0.005^c 0.6±0.1 -0.04±0.14
II 7.88±0.25 0.010±0.005^c 0.5±0.1 -0.17±0.11
III 8.21±0.29 0.010±0.005^d 0.4±0.1 -0.14±0.08
IV 8.65±0.36 (3±2)e-3^d 0.4±0.0 -0.10±0.20
V 9.09±0.29 (4±2)e-3^d 1.4±0.1 -0.17±0.13
VI 9.45±0.28 (2±1)e-3^d 2.4±0.1 -0.07±0.09
VII 9.82±0.29 (7±4)e-4^d 2.4±0.3 -0.08±0.08
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c=Cohen (1982ApJ...258..143C 1982ApJ...258..143C)
d=Frogel+ (1990ApJ...352...96F 1990ApJ...352...96F), assuming Z☉=0.017.
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History:
From electronic version of the journal
References:
Gonzalez-Lopezlira et al. Paper I. 2010MNRAS.403.1213G 2010MNRAS.403.1213G Cat. J/MNRAS/403/1213
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 14-Feb-2019