J/A+A/626/A92 Spitzer/IRS analysis of the 30-micron sources (Gladkowski+, 2019)
30-micron sources in galaxies with different metallicities.
Gladkowski M., Szczerba R., Sloan G. C., Lagadec E., Volk K.
<Astron. Astrophys. 626, A92 (2019)>
=2019A&A...626A..92G 2019A&A...626A..92G (SIMBAD/NED BibCode)
ADC_Keywords: Stars, carbon ; Stars, S ; Planetary nebulae ; Spectra, infrared ;
Infrared sources ; Magellanic Clouds; Milky Way ;
Galaxies, nearby ; Spectroscopy
Keywords: catalogs - stars: AGB and post-AGB - planetary nebulae: general -
galaxies: individual: Milky Way - Magellanic Clouds -
galaxies: individual: Sagittarius Dwarf Spheroid galaxy
Abstract:
We present an analysis and comparison of the 30µm dust features
seen in the Spitzer Space Telescope spectra of 207 carbon-rich
asymptotic giant branch (AGB) stars, post-AGB objects, and planetary
nebulae (PNe) located in the Milky Way, the Magellanic Clouds (MCs),
or the Sagittarius dwarf spheroidal galaxy (Sgr dSph), which are
characterised by different average metallicities. We investigated
whether the formation of the 30µm feature carrier may be a function
of the metallicity. Through this study we expect to better understand
the late stages of stellar evolution of carbon-rich stars in these
galaxies. Our analysis uses the "Manchester method" as a basis for
estimating the temperature of dust for the carbon-rich AGB stars and
the PNe in our sample. For post-AGB objects we changed the wavelength
ranges used for temperature estimation, because of the presence of the
21µm feature on the short wavelength edge of the 30µm feature.
We used a black-body function with a single temperature deduced from
the Manchester method or its modification to approximate the continuum
under the 30µm feature. We find that the strength of the 30µm
feature increases until dust temperature drops below 400K. Below this
temperature, the large loss of mass and probably the self-absorption
effect reduces the strength of the feature. During the post-AGB phase,
when the intense mass-loss has terminated, the optical depth of the
circumstellar envelope is smaller, and the 30{um}m feature becomes
visible again, showing variety of values for post-AGB objects and PNe,
and being comparable with the strengths of AGB stars. In addition, the
AGB stars and post-AGB objects show similar values of central
wavelengths - usually between 28.5 and 29.5µm. However, in case of
PNe the shift of the central wavelength towards longer wavelengths is
visible. The normalised median profiles for AGB stars look uniformly
for various ranges of dust temperature, and different galaxies. We
analysed the profiles of post-AGB objects and PNe only within one dust
temperature range (below 200K), and they were also similar in
different galaxies. In the spectra of 17 PNe and five post-AGB objects
we found the broad 16-24µm feature. Two objects among the PNe group
are the new detections: SMP LMC 51, and SMP LMC 79, whereas in the
case of post-AGBs the new detections are: IRAS 05370-7019,
IRAS 05537-7015, and IRAS 21546+4721. In addition, in the spectra of
nine PNe we found the new detections of 16-18µm feature. We also
find that the Galactic post-AGB object IRAS 11339-6004 has a 21µm
emission. Finally, we have produced online catalogues of photometric
data and Spitzer IRS spectra for all objects that show the 30µm
feature. These resources are available online for use by the
community. The most important conclusion of our work is the fact that
the formation of the 30µm feature is affected by metallicity.
Specifically that, as opposed to more metal-poor samples of AGB stars
in the MCs, the feature is seen at lower mass-loss rates, higher
temperatures, and has seen to be more prominent in Galactic carbon
stars. The averaged feature (profile) in the AGB, post-AGB objects,
and PNe seems unaffected by metallicity at least between a fifth and
solar metallicity, but in the case of PNe it is shifted to
significantly longer wavelengths.
Description:
Tables d1-d3 list the basic information about the 30 micron objects in
the SMC (22 objects), LMC (121 objects), and the Milky Way (59
objects), respectively. The objects which names are marked by * at the
end (they names are in bold face in the paper), are excluded from
further analysis.
Tables d4-d6 list the results of the spectroscopic analysis (Spitzer
IRS) for objects in the SMC, LMC, and the Milky Way, respectively.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tabled1.dat 159 22 The SMC sample of the 30-micron sources
tabled2.dat 159 121 The LMC sample of the 30-micron sources
tabled3.dat 159 59 The Milky Way sample of the 30-micron sources
tabled4.dat 130 22 Spectroscopic results for the SMC objects
tabled5.dat 130 121 Spectroscopic results for the LMC objects
tabled6.dat 130 59 Spectroscopic results for the Milky Way objects
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See also:
J/ApJ/826/44 : Spitzer/IRS obs. of Magellanic carbon stars (Sloan+, 2016)
J/A+A/609/A114 : Local Group AGB st. and red supergiants (Groenewegen+, 2018)
Byte-by-byte Description of file: tabled1.dat tabled2.dat tabled3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 24 A24 --- Name Name
25 A1 --- n_Name [*] Note on Name (G1)
26- 48 A23 --- OName Other name
49- 55 F7.3 deg RAdeg Right Ascension in decimal degrees (J2000)
57- 63 F7.3 deg DEdeg Declination in decimal degrees (J2000)
65- 69 A5 --- Ref Position reference (IRAC)
71-123 A53 --- Class Classification of the object (2)
124 A1 --- l_Per [~] Limit flag on Per
125-127 I3 d Per ? Period or lower value of Period interval
128 A1 --- --- [-]
129-130 I2 d Per2 ? Upper value of period interval
132-133 I2 --- r_Per ? Reference for Per (3)
135-136 I2 --- PID1 ? The 1-st Program identifier
(only in tabled3.dat)
138-142 I5 --- PID Program identifier or
2-nd Program identifier in tabled3.dat
144-150 I7 --- AOR1 ? The 1-st Spitzer Astronomical Obs. Request
(only in tabled3.dat)
152-159 I8 --- AOR Spitzer Astronomical Observation Request or
2-nd Spitzer Astronomical Obs. Request
in tabled3.dat
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Note (2): References as follows:
a = Volk et al. (2011ApJ...735..127V 2011ApJ...735..127V)
b = Bernard-Salas et al. (2009ApJ...699.1541B 2009ApJ...699.1541B)
c = Garcia-Hernandez (2010ApJ...724L..39G 2010ApJ...724L..39G)
d = Bernard-Salas et al. (2012ApJ...757...41B 2012ApJ...757...41B)
e = Garcia-Hernandez et al. (2012ApJ...760..107G 2012ApJ...760..107G)
f = Sloan et al. (2014ApJ...791...28S 2014ApJ...791...28S)
g = Garcia-Hernandez et al. (2012ApJ...760..107G 2012ApJ...760..107G)
h = Matsuura et al. (2014MNRAS.439.1472M 2014MNRAS.439.1472M)
i = Otsuka (2015MNRAS.452.4070O 2015MNRAS.452.4070O)
j = Kwok et al. (1989ApJ...345L..51K 1989ApJ...345L..51K)
k = Hrivnak et al. (2009ApJ...694.1147H 2009ApJ...694.1147H)
l = Cami et al. (2010Sci...329.1180C 2010Sci...329.1180C)
m = Zhang et al. (2010ApJ...725..990Z 2010ApJ...725..990Z)
n = Cerrigone et al. (2011ApJ...738..121C 2011ApJ...738..121C)
o = Zhang & Kwok (2011ApJ...730..126Z 2011ApJ...730..126Z)
p = Smolders et al. (2012A&A...540A..72S 2012A&A...540A..72S)
q = Otsuka et al. (2013ApJ...764...77O 2013ApJ...764...77O)
r = Otsuka et al. (2014MNRAS.437.2577O 2014MNRAS.437.2577O)
s = Raman et al. (2017MNRAS.470.1593R 2017MNRAS.470.1593R)
The classes and additional notes after them are defined as follows:
C-AGB = C-rich AGB star
C-pAGB = C-rich post-AGB star
C-PN = C-rich planetary nebula
gr. I = C-rich post-AGB ob. without (or with weak) a 21um feature
gr. II = C-rich post-AGB ob. with a relat. strong 21um feature
gr. III = C-rich post-AGB object with a strong 21um feature
S-type star = S-type AGB star
21 micron = object with a 21 micron dust feature (post-AGB)
16-24 micron feat. = object with the 16-24 micron dust feature
? - presence of the feature is not certain
16-18 micron feat. = object with the 16-18 micron dust feature
C2H2 = C-rich post-AGB object with a C2H2 band
fullerenes = object shows fullerene emission
Note (3): Reference as follows:
1 = Whitelock et al. (1989MNRAS.238..769W 1989MNRAS.238..769W)
2 = Sloan et al. (2006ApJ...645.1118S 2006ApJ...645.1118S)
3 = Kamath et al. (2010MNRAS.408..522K 2010MNRAS.408..522K)
4 = Soszynski et al. (2011AcA....61..217S 2011AcA....61..217S)
5 = Hrivnak et al. (2015ApJ...805...78H 2015ApJ...805...78H)
21 = Whitelock et al. (2003MNRAS.342...86W 2003MNRAS.342...86W)
22 = Groenewegen et al. (2009A&A...506.1277G 2009A&A...506.1277G)
23 = Soszynski et al. (2009AcA....59..239S 2009AcA....59..239S)
24 = Kamath et al. (2010MNRAS.408..522K 2010MNRAS.408..522K)
25 = Hrivnak et al. (2015ApJ...805...78H 2015ApJ...805...78H)
26 = Sloan et al. (2016ApJ...826...44S 2016ApJ...826...44S)
31 = Hrivnak et al. (2010ApJ...709.1042H 2010ApJ...709.1042H)
32 = Smolders et al. (2012A&A...540A..72S 2012A&A...540A..72S)
33 = Mauron et al. (2014A&A...562A..24M 2014A&A...562A..24M)
34 = Samus et al. (2017ARep...61...80S 2017ARep...61...80S)
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Byte-by-byte Description of file: tabled4.dat tabled5.dat tabled6.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 24 A24 --- Name Name of the object
25 A1 --- n_Name [*] Note on Name (G1)
26- 30 F5.3 mag Colour1 ? The ([5.8]-[9.3]) colour index
32- 36 F5.3 mag e_Colour1 ? Uncertainty in Colour1
38- 42 F5.3 mag Colour2 ? The ([6.4]-[9.3]) colour index
44- 48 F5.3 mag e_Colour2 ? Uncertainty in Colour2
50- 54 F5.3 mag Colour3 ? The ([16.5]-[21.5]) col. index
56- 60 F5.3 mag e_Colour3 ? Uncertainty in Colour3
62- 66 F5.3 mag Colour4 ? The ([18.4]-[22.45]) colour index
68- 72 F5.3 mag e_Colour4 ? Uncertainty in Colour4
74- 78 F5.3 mag Colour5 ? The ([18.4]-[22.75]) colour index
80- 84 F5.3 mag e_Colour5 ? Uncertainty in Colour5
86- 90 F5.3 mag Colour6 ? The ([17.95]-[23.2]) colour index
92- 96 F5.3 mag e_Colour6 ? Uncertainty in Colour6
98-101 I4 K Td ? The dust temperature
103-105 I3 K e_Td ? Uncertainty in Td
107-112 F6.3 um Lc ? Central wav. of 30um feature
114-118 F5.3 um e_Lc ? Uncertainty in Lc
120-124 F5.3 --- F/Cont ? Strength of the 30um feature
126-130 F5.3 --- e_F/Cont ? Uncertainty in F/Cont
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Global notes:
Note (G1): The objects removed from the futher analysis (see Section 3.1) in the
paper are marked by the bold faced names. Here, they are marked by
the star marker (*).
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Acknowledgements:
Marcin Gladkowski, seyfert(at)ncac.torun.pl
(End) Patricia Vannier [CDS] 27-May-2019