J/ApJ/851/152 DUSTiNGS. IV. AGB spectral types with HST (Boyer+, 2017)
An infrared census of DUST in Nearby Galaxies with Spitzer (DUSTiNGS).
IV. Discovery of high-redshift AGB analogs.
Boyer M.L., McQuinn K.B.W., Groenewegen M.A.T., Zijlstra A.A.,
Whitelock P.A., van Loon J.T., Sonneborn G., Sloan G.C., Skillman E.D.,
Meixner M., McDonald I., Jones O.C., Javadi A., Gehrz R.D., Britavskiy N.,
Bonanos A.Z.
<Astrophys. J., 851, 152 (2017)>
=2017ApJ...851..152B 2017ApJ...851..152B
ADC_Keywords: Galaxies, nearby; Stars, giant; Photometry, infrared
Keywords: galaxies: dwarf ; stars: AGB and post-AGB ; stars: carbon ;
stars: mass-loss ; techniques: photometric
Abstract:
The survey for DUST in Nearby Galaxies with Spitzer (DUSTiNGS)
identified several candidate Asymptotic Giant Branch (AGB) stars in
nearby dwarf galaxies and showed that dust can form even in very
metal-poor systems (Z∼0.008Z☉). Here, we present a follow-up
survey with WFC3/IR on the Hubble Space Telescope (HST), using filters
that are capable of distinguishing carbon-rich (C-type) stars from
oxygen-rich (M-type) stars: F127M, F139M, and F153M. We include six
star-forming DUSTiNGS galaxies (NGC147, IC10, Pegasus dIrr, SextansB,
SextansA, and Sag DIG), all more metal-poor than the Magellanic Clouds
and spanning 1dex in metallicity. We double the number of dusty AGB
stars known in these galaxies and find that most are carbon rich. We
also find 26 dusty M-type stars, mostly in IC 10. Given the large dust
excess and tight spatial distribution of these M-type stars, they are
most likely on the upper end of the AGB mass range (stars undergoing
Hot Bottom Burning). Theoretical models do not predict significant
dust production in metal-poor M-type stars, but we see evidence for
dust excess around M-type stars even in the most metal-poor galaxies
in our sample (12+log(O/H)=7.26-7.50). The low metallicities and
inferred high stellar masses (up to ∼10M☉) suggest that AGB
stars can produce dust very early in the evolution of galaxies (∼30Myr
after they form), and may contribute significantly to the dust
reservoirs seen in high-redshift galaxies.
Description:
We observed six DUSTiNGS galaxies with HST's WFC3/IR in Cycle 23 as
part of GO-14073 from 2016 October to 2016 August.
The HST catalog was matched to the Spitzer MIR catalog
(see section 2.3).
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 75 6 Target information
catalog.dat 125 4129 The HST-Spitzer catalog (table 3; updated
version from the author)
table7.dat 107 26 Dusty M-type AGB stars
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See also:
VI/125 : Theoretical spectra of red giants and supergiants (Lancon+, 2007)
J/A+A/403/93 : Photom. of AGB stars in NGC 185 and NGC 147 (Nowotny+, 2003)
J/A+A/448/181 : IR colours of AGB and post-AGB stars (Groenewegen+, 2006)
J/MNRAS/376/313 : Carbon star in Magellanic Cloud (Groenewegen+, 2007)
J/ApJ/664/850 : Spitzer observations of stars in M33 (McQuinn+, 2007)
J/AJ/135/1395 : omega Cen Spitzer photometry (Boyer+, 2008)
J/A+A/503/913 : Synthetic spectrophotom. for C-rich giants (Aringer+, 2009)
J/A+A/506/1277 : Magellanic Cloud C/O stars modelisation (Groenewegen+, 2009)
J/MNRAS/394/795 : AGB stars in Fornax dSph galaxy (Whitelock+, 2009)
J/ApJ/711/361 : Local Group dE galaxies. II. (Geha+, 2010)
J/PASP/122/683 : SAGE-Spec Spitzer legacy program (Kemper+, 2010)
J/ApJ/715/1094 : Census of self-obscured massive stars (Khan+, 2010)
J/AJ/142/103 : Cool evolved stars in SAGE-SMC and SAGE-LMC (Boyer+, 2011)
J/A+A/532/A78 : Long-period variables in NGC 147 and NGC 185 (Lorenz+, 2011)
J/ApJS/193/23 : Fundamental parameters in 47 Tucanae (McDonald+, 2011)
J/MNRAS/414/3492 : JHKs photometry of Sculptor dSph galaxy (Menzies+, 2011)
J/ApJ/758/11 : Bayesian distances to M31 satellites (Conn+, 2012)
J/AJ/144/4 : Dwarf galaxies in the Local Group (McConnachie+, 2012)
J/ApJ/753/71 : Mass-loss return from LMC evolved stars. VI. (Riebel+, 2012)
J/A+A/566/A44 : gr photometry of Sextans A and Sextans B (Bellazzini+, 2014)
J/MNRAS/440/631 : IR photometry of LMC O-rich evolved stars (Jones+, 2014)
J/MNRAS/439/2618 : VISTA variables in Sagittarius dSph (McDonald+, 2014)
J/A+A/571/A43 : Cand. red supergiants in Galactic clusters (Messineo+, 2014)
J/A+A/572/A42 : SagDIG carbon and oxygen stars (Momany+, 2014)
J/ApJ/789/147 : Star formation histories of LG dwarf galaxies (Weisz+, 2014)
J/ApJ/810/116 : S-type AGB stars in SMC (Boyer+, 2015)
J/ApJS/216/10 : DUSTiNGS. I. The Good Source Catalog (Boyer+, 2015)
J/ApJ/800/51 : DUSTiNGS II. Metal-poor dusty AGB stars (Boyer+, 2015)
J/MNRAS/452/910 : IC 1613 asymptotic giant branch variables (Menzies+, 2015)
J/MNRAS/451/3504 : Classification of IRS sources in the SMC (Ruffle+, 2015)
J/ApJ/826/44 : Spitzer/IRS obs. of Magellanic carbon stars (Sloan+, 2016)
J/MNRAS/457/2814 : SAGE SMC evolved stars candidates (Srinivasan+, 2016)
J/MNRAS/470/3250 : SAGE LMC point-sources classification (Jones+, 2017)
J/ApJ/839/88 : 14 IR transients with Spitzer (SPRITEs) (Kasliwal+, 2017)
J/ApJ/834/9 : Spectrosc. obs. of LeoA, Aqr & Sgr dwarf gal. (Kirby+, 2017)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Gal Galaxy name
14- 20 A7 --- AName Alternative name
22- 32 A11 --- TType Morphological type
34- 37 F4.2 Mpc Dist [0.7/1.5] Distance derived from F814W (I-band)
TRGB estimates (1)
39- 43 F5.2 [Sun] [Fe/H] [-2.1/-1.1] [Fe/H] abundance (2)
45- 48 F4.2 [Sun] e_[Fe/H] [0.1/0.2]? [Fe/H] uncertainty
50- 53 F4.2 [-] logOH [0/8.2]? 12+log(O/H) abundance (3)
55- 58 F4.2 [-] e_logOH [0.05/0.2]? logOH uncertainty
60 A1 --- f_logOH [a] a: Range 7.26-7.50
62- 66 F5.1 mag VMag [-15/-11.5] V-band absolute magnitude from
McConnachie (2012, J/AJ/144/4) and references
therein
68- 70 F3.1 mag e_VMag [0.1/0.3] VMag uncertainty
72- 75 F4.2 mag Av [0.09/2.4] Av from Weisz+ (2014, J/ApJ/789/147)
--------------------------------------------------------------------------------
Note (1): from McQuinn+ (Paper III, 2017ApJ...834...78M 2017ApJ...834...78M).
Note (2): The values of [Fe/H] adopted here are derived from RGB colors from
Nowotny+ (2003, J/A+A/403/93), Bellazzini+ (2014, J/A+A/566/A44),
Tikhonov & Galazutdinova (2009, J/PAZh/35/829),
McConnachie+ (2005MNRAS.356..979M 2005MNRAS.356..979M), Momany+ (2002A&A...384..393M 2002A&A...384..393M), and
Sakai+ (1996ApJ...461..713S 1996ApJ...461..713S). Stellar metallicities are derived from
spectroscopy of RGB stars in NGC 147 agree with our adopted value
(Geha+ 2010, J/ApJ/711/361). However, Kirby+ (2017, J/ApJ/834/9)
measured [Fe/H]=-1.88-0.09+0.13 from RGB star spectroscopy in
Sag DIG.
Note (3): ISM gas-phase oxygen abundances (12+log(O/H) are from
Mateo (1998ARA&A..36..435M 1998ARA&A..36..435M), Lee+ (2006ApJ...647..970L 2006ApJ...647..970L), and
Saviane+ (2002A&A...390...59S 2002A&A...390...59S).
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Byte-by-byte Description of file: catalog.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- ID [100035/602411] Identification number
8- 13 I6 --- DUST [37492/167198]?=-99 DUSTiNGS identifier (G1)
15- 26 A12 --- Gal Galaxy identifier
28- 29 I2 h RAh Hour of Right Ascension (J2000) (1)
31- 32 I2 min RAm Minute of Right Ascension (J2000) (1)
34- 38 F5.2 s RAs Second of Right Ascension (J2000) (1)
40 A1 --- DE- Sign of the Declination (J2000) (1)
41- 42 I2 deg DEd Degree of Declination (J2000) (1)
44- 45 I2 arcmin DEm Arcminute of Declination (J2000) (1)
47- 50 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1)
52- 57 F6.3 mag F127Mmag [15.2/23.6] HST/WFC3 F127M filter magnitude (2)
59- 63 F5.3 mag e_F127Mmag [0.001/0.2] The 1σ error on F127Mmag
65- 70 F6.3 mag F139Mmag [15/22.8] HST/WFC3 F139M filter magnitude (2)
72- 76 F5.3 mag e_F139Mmag [0.001/0.2] The 1σ error on F139Mmag
78- 83 F6.3 mag F153Mmag [14.6/22.4] HST/WFC3 F153M filter magnitude (2)
85- 89 F5.3 mag e_F153Mmag [0.001/0.2] The 1σ error on F153Mmag
91- 96 F6.2 mag 3.6mag [13.1/20]?=-99 Spitzer/IRAC 3.6 micron band
magnitude (2)(3)
98-103 F6.2 mag e_3.6mag [0.02/0.3]?=-99 The 1σ error on 3.6mag
105-110 F6.2 mag 4.5mag [12.8/20.3]?=-99 Spitzer/IRAC 4.5 micron band
magnitude (2)(3)
112-117 F6.2 mag e_4.5mag [0.02/0.3]?=-99 The 1σ error on 4.5mag
119 A1 --- Class C-type (carbon-rich) or
M-type (oxygen-rich) classification;
see Section 2.4
121 I1 --- Var [0/1] x-AGB variable flag (4)
123 I1 --- D [0/1] Dusty flag (5)
125 I1 --- C [0/1] Contamination flag (6)
--------------------------------------------------------------------------------
Note (1): Positions are the uncorrected HST coordinates (accuracy
approximately 200mas).
Note (2): Magnitudes are not corrected for extinction.
Note (3): Magnitudes are from the coadded epochs (∼180 days separation).
See Paper I (Boyer+ 2015, J/ApJS/216/10).
Note (4): The x-AGB variables identified in Paper II (Boyer+ 2015, J/ApJ/800/51)
Note (5): Sources with >4σ excess in [3.6]-[4.5].
Note (6): Sources that are suspected contaminants (Section 2.5).
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Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Gal Galaxy name
11- 16 I6 --- DUST [44334/123385] DUSTiNGS identifier (G1)
18- 19 I2 h RAh Hour of right ascension (J2000)
21- 22 I2 min RAm Minute of right ascension (J2000)
24- 28 F5.2 s RAs Second of right ascension (J2000)
30 A1 --- DE- Sign of declination (J2000)
31- 32 I2 deg DEd Degree of declination (J2000)
34- 35 I2 arcmin DEm Arcminute of declination (J2000)
37- 41 F5.2 arcsec DEs Arcsecond of declination (J2000)
43- 48 F6.3 mag F127Mmag [15.6/23] HST/WFC3 F127M filter magnitude,
corrected for extinction
50- 54 F5.3 mag e_F127Mmag [0.001/0.1] F127Mmag uncertainty
56- 61 F6.3 mag F139Mmag [15.5/22.8] HST/WFC3 F139M filter magnitude,
corrected for extinction
63- 67 F5.3 mag e_F139Mmag [0.001/0.2] F139Mmag uncertainty
69- 74 F6.3 mag F153Mmag [14.9/22] HST/WFC3 F153M filter magnitude,
corrected for extinction
76- 80 F5.3 mag e_F153Mmag [0.001/0.07] F153Mmag uncertainty
82- 86 F5.2 mag 3.6mag [13/18.5] Spitzer/IRAC 3.6 um magnitude (1)
88- 91 F4.2 mag e_3.6mag [0.02/0.1] 3.6mag uncertainty
92 A1 --- f_3.6mag [a] Flag on 3.6mag (2)
94- 98 F5.2 --- 4.5mag [12.8/17.5] Spitzer/IRAC 4.5 um magnitude (1)
100-103 F4.2 --- e_4.5mag [0.03/0.08] 4.5mag uncertainty
105-107 A3 --- Note Note(s) (3)
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Note (1): The Spitzer magnitudes are from the DUSTiNGS survey (Boyer+, 2015,
Paper I, J/ApJS/216/10 & II, J/ApJ/800/51).
Note (2):
a = The IRAC magnitudes listed for 112431 are from DUSTiNGS epoch 2 because
the star is not as red in epoch 1 (<4σ excess; Paper I
(Boyer+, 2015, J/ApJS/216/10)).
Note (3): M-type AGB stars as follows:
H = High-confidence AGB star: HST colors indicate water absorption;
L = Low-confidence AGB star: star is near the border of C and M stars,
is near the contamination cutoff in Figure 8, or is affected by crowding.
x = DUSTiNGS x-AGB variable (those with >3σ variability between two
Spitzer epochs, i.e., a likely AGB star). Non-x-AGB stars may also be
variable, but were observed by DUSTiNGS with an unfavorable cadence.
--------------------------------------------------------------------------------
Global note:
Note (G1): The sources are named in Simbad.
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History:
From electronic version of the journal
Table 3 has been fixed for the duplicated Spitzer/IRAC magnitudes in 3.6um
and 4.5um for NGC 147.
References:
Boyer et al. Paper I. 2015ApJS..216...10B 2015ApJS..216...10B Cat. J/ApJS/216/10
Boyer et al. Paper II. 2015ApJ...800...51B 2015ApJ...800...51B Cat. J/ApJ/800/51
McQuinn et al. Paper III. 2017ApJ...834...78M 2017ApJ...834...78M
Boyer et al. Paper IV. 2017ApJ...851..152B 2017ApJ...851..152B This catalog
Acknowledgements:
Martha Boyer [Space Telescope Science Institute; STScI]
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 10-Jul-2018