J/A+A/579/A76 Galactic bulge extremely reddened AGB (Jimenez-Esteban+, 2015)
Study of extremely reddened AGB stars in the Galactic bulge.
Jimenez-Esteban F.M., Engels D.
<Astron. Astrophys., 579, A76-76 (2015)>
=2015A&A...579A..76J 2015A&A...579A..76J (SIMBAD/NED BibCode)
ADC_Keywords: Stars, giant ; Infrared sources ; Photometry, infrared
Keywords: stars: AGB and post-AGB - circumstellar matter - stars: evolution -
stars: variables: general - Galaxy: bulge - infrared: stars
Abstract:
Extremely reddened asymptotic giant branch stars (AGB) lose mass at
high rates of >10-5M☉/yr. This is the very last stage of AGB
evolution, in which stars in the mass range ∼2.0-4.0M☉ (for
solar metallicity) should have been converted to C stars already. The
extremely reddened AGB stars in the Galactic bulge are however
predominantly O-rich, implying that they might be either low-mass
stars or stars at the upper end of the AGB mass range. Our goal is to
determine the mass range of the most reddened AGB stars in the
Galactic bulge. Using Virtual Observatory tools, we constructed
spectral energy distributions of a sample of 37 evolved stars in the
Galactic bulge with extremely red IRAS colours. We fitted DUSTY models
to the observational data to infer the bolometric fluxes. Applying
individual corrections for interstellar extinction and adopting a
common distance, we determined luminosities and mass-loss rates, and
inferred the progenitor mass range from comparisons with AGB
evolutionary models. The observed spectral energy distributions are
consistent with a classification as reddened AGB stars, except for two
stars, which are proto-planetary nebula candidates. For the AGB stars,
we found luminosities in the range ∼3000-30000L☉ and mass-loss
rates ∼10-5-3x10-4M☉/yr. The corresponding mass range is
∼1.1-6.0M☉ assuming solar metallicity. Contrary to the
predictions of the evolutionary models, the luminosity distribution is
continuous, with many O-rich AGB stars in the mass range in which they
should have been converted into C stars already. We suspect that bulge
AGB stars have higher than solar metallicity and therefore may avoid
the conversion to C-rich. The presence of low-mass stars in the sample
shows that their termination of the AGB evolution also occurs during a
final phase of very high mass-loss rate, leading to optically thick
circumstellar shells.
Description:
Our sample of AGB stars of the Galactic bulge (hereafter: GB sample)
was selected from the sample of sources in Jimenez-Esteban et al.
(2006A&A...446..773J 2006A&A...446..773J, Cat. J/A+A/446/773).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 103 37 Galactic Bulge (GB) sample: observational parameters
table2.dat 490 45 Photometric data collected
--------------------------------------------------------------------------------
See also:
J/A+A/431/779 : Optical/near-IR atlas of OH/IR stars (Jimenez-Esteban+, 2005)
J/A+A/446/773 : GLMP sample of galactic OH/IR stars (Jimenez-Esteban+, 2006)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- IRAS IRAS name
12- 13 I2 h RAh WISE right ascension (J2000)
15- 16 I2 min RAm WISE right ascension (J2000)
18- 22 F5.2 s RAs WISE right ascension (J2000)
24 A1 --- DE- WISE declination sign (J2000)
25- 26 I2 deg DEd WISE declination (J2000)
28- 29 I2 arcmin DEm WISE declination (J2000)
31- 34 F4.1 arcsec DEs WISE declination (J2000)
36- 45 F10.6 deg GLON WISE galactic longitude
47- 55 F9.6 deg GLAT WISE galactic latitude
57- 60 F4.2 mag [12]-[25] IRAS [12]-[25] colour (1)
62- 66 F5.2 mag [25]-[60] IRAS [25]-[60] colour (1)
68- 70 A3 --- LRS [AI- ] IRAS low resolution spectra
71 A1 --- n_LRS [c] c: Classification by this work
(see Sects. 2 and 3.1)
73- 74 I2 --- Var IRAS variability index
76- 77 A2 --- OH [Y/N Sp] OH radio detection (2)
79 A1 --- H2O [Y/N] H2O radio detection (2)
81 A1 --- SiO [Y/N] SiO radio detection (2)
83- 86 F4.1 km/s Vexp ? Expansion velocity from the OH maser
velocity range, or from CO data for
IRAS 17495-2534
87 A1 --- n_Vexp [f] f: Expansion velocity from CO data
89- 92 F4.2 mag AKs Absorption in Ks band
94-103 A10 --- Com Comment (3)
--------------------------------------------------------------------------------
Note (1): IRAS colours as defined in Jimenez-Esteban et al.
(2005A&A...431..779J 2005A&A...431..779J, Cat. J/A+A/431/779).
Note (2): Radio data code as follows:
Y = detection
N = no detection
Sp = single peak
Note (3): SED peculiarities (see Sect. 3.1) as follows:
DP = double peaked
NIR-Exc = near-infrared excess
FIR-Exc = far-infrared excess
PPN = proto-planetary nebula candidate
PPN(c) = proto-planetary nebula candidate, classification by this work
(see Sects. 2 and 3.1)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- IRAS IRAS name
12 A1 --- n_IRAS [d] Note (1)
14 A1 --- n_FJ [ab] Note on J filter values (2)
16 A1 --- l_FJ Upper limit flag on FJ
18- 26 E9.4 Jy FJ ? Flux in 2MASS/VISTA J band (1.25um)
28- 34 E7.2 Jy e_FJ ? rms uncertainty on FJ
36 A1 --- n_FH [ab] Note on H filter values (2)
38 A1 --- l_FH Upper limit flag on FH
40- 48 E9.4 Jy FH ? Flux in 2MASS/VISTA H band (1.65um)
50- 56 E7.2 Jy e_FH ? rms uncertainty on FH
58 A1 --- n_FKs [ab] Note on Ks filter values (2)
60 A1 --- l_FKs Upper limit flag on FKs
62- 70 E9.4 Jy FKs Flux in 2MASS/VISTA Ks band (2.20um)
72- 78 E7.2 Jy e_FKs ? rms uncertainty on FKs
80 A1 --- l_FW1 Upper limit flag on FW1
82- 90 E9.4 Jy FW1 ? Flux in WISE W1 band (3.4um)
92- 98 E7.2 Jy e_FW1 ? rms uncertainty on FW1
100-108 E9.4 Jy FI1 ? Flux in GLIMPSE I1 band (3.56um)
110-116 E7.2 Jy e_FI1 ? rms uncertainty on FI1
118-126 E9.4 Jy FI2 ? Flux in GLIMPSE I2 band (4.51um)
128-134 E7.2 Jy e_FI2 ? rms uncertainty on FI2
136-144 E9.4 Jy FW2 ? Flux in WISE W2 band (4.6um)
146-152 E7.2 Jy e_FW2 ? rms uncertainty on FW2
154-162 E9.4 Jy FI3 ? Flux in GLIMPSE I3 band (5.76um)
164-170 E7.2 Jy e_FI3 ? rms uncertainty on FI3
172-180 E9.4 Jy FI4 ? Flux in GLIMPSE I4 band (7.96um)
182-188 E7.2 Jy e_FI4 ? rms uncertainty on FI4
190-198 E9.4 Jy FA ? Flux in MSX6C A band (8.28um)
200-206 E7.2 Jy e_FA ? rms uncertainty on FA
208-216 E9.4 Jy FS09 ? Flux in AKARI S09 band (9um)
218-224 E7.2 Jy e_FS09 ? rms uncertainty on FS09
226-234 E9.4 Jy FW3 ? Flux in WISE W3 band (11.6um)
236-242 E7.2 Jy e_FW3 ? rms uncertainty on FW3
244-252 E9.4 Jy F12 ? Flux in IRAS 12um band
254-260 E7.2 Jy e_F12 ? rms uncertainty on F12
262 A1 --- l_FC Upper limit flag on FC
264-272 E9.4 Jy FC ? Flux in MSX6C C band (12.13um)
274-280 E7.2 Jy e_FC ? rms uncertainty on FC
282-290 E9.4 Jy FD ? Flux in MSX6C D band (14.65um)
292-298 E7.2 Jy e_FD ? rms uncertainty on FD
300-308 E9.4 Jy FS18 ? Flux in AKARI S18 band (18um)
310-316 E7.2 Jy e_FS18 ? rms uncertainty on FS18
318 A1 --- l_FE Upper limit flag on FE
320-328 E9.4 Jy FE ? Flux in MSX6C E band (21.3um)
330-336 E7.2 Jy e_FE ? rms uncertainty on FE
338-346 E9.4 Jy FW4 ? Flux in WISE W4 band (22.1um)
348-354 E7.2 Jy e_FW4 ? rms uncertainty on FW4
356-364 E9.4 Jy F25 ? Flux in IRAS 25um band
366-372 E7.2 Jy e_F25 ? rms uncertainty on F25
374-382 E9.4 Jy F60 ? Flux in IRAS 60um band
384-390 E7.2 Jy e_F60 ? rms uncertainty on F60
392 A1 --- f_FS65 [c] Flag on FS65 (2)
394 A1 --- l_FS65 Upper limit flag on FS65
396-404 E9.4 Jy FS65 ? Flux in AKARI S65 band (65um)
406-412 E7.2 Jy e_FS65 ? rms uncertainty on FS65
414 A1 --- f_FS90 [c] Flag on FS90 (2)
416 A1 --- l_FS90 Upper limit flag on FS90
418-426 E9.4 Jy FS90 ? Flux in AKARI S90 band (90um)
428-434 E7.2 Jy e_FS90 ? rms uncertainty on FS90
436 A1 --- l_F100 Upper limit flag on F100
438-446 E9.4 Jy F100 ? Flux in IRAS 100um band
448 A1 --- f_FS140 [c] Flag on FS140 (2)
450 A1 --- l_FS140 Upper limit flag on FS140
452-460 E9.4 Jy FS140 ? Flux in AKARI S140 band (140um)
462-468 E7.2 Jy e_FS140 ? rms uncertainty on FS140
470 A1 --- f_FS160 [c] Flag on FS160 (2)
472 A1 --- l_FS160 Upper limit flag on FS160
474-482 E9.4 Jy FS160 ? Flux in AKARI S160 band (160um)
484-490 E7.2 Jy e_FS160 ? rms uncertainty on FS160
--------------------------------------------------------------------------------
Note (1): d: For IRAS 17276-2846, VVV-DR1 fluxes in 10-5Jy:
Fz=761±2 and FY=3017±4.
Note (2): Notes as follows:
a = 2MASS data
b = VVV-DR1 data
c = no confirmed detection
--------------------------------------------------------------------------------
Acknowledgements:
Francisco Jimenez-Esteban [Centro de Astrobiologia (CSIC-INTA), Spain]
History:
* 11-Jan-2017: From electronic version of the journal
* 04-Dec-2018: Table 2 updated (from author)
(End) Patricia Vannier [CDS] 01-Oct-2015