J/A+A/376/997 Galactic mass-losing AGB stars (Le Bertre+, 2001)
Galactic mass-losing AGB stars probed with the IRTS. I.
Le Bertre T., Matsuura M., Winters J.M., Murakami H., Yamamura I.,
Freund M., Tanaka M.
<Astron. Astrophys. 376, 997 (2001)>
=2001A&A...376..997L 2001A&A...376..997L
ADC_Keywords: Stars, carbon ; Mass loss ; Infrared sources ; Stars, distances
Keywords: stars: carbon - stars: mass-loss - stars: AGB and post-AGB -
ISM: evolution - galaxy: solar neighbourhood - infrared: stars
Abstract:
AGB mass-losing sources are easy to identify and to characterize in
the near-infrared range (1-5µm). We make use of the near-infrared
data acquired by the Japanese space experiment IRTS to study a sample
of sources detected in the 2 celestial strips surveyed by the IRTS.
Mass-loss rates and distances are estimated for 40 carbon-rich sources
and 86 oxygen-rich sources of which 8 are probably of S-type. Although
the sample is small, one sees a dependence of the relative
contribution of the two kinds of sources to the replenishment of the
interstellar medium (ISM) on the galactocentric distance. E.g. from 6
to 8kpc, oxygen-rich sources in our sample contribute 10-12 times as
much as carbon rich sources, whereas from 10 to 12kpc, the latters
contribute 3-4 times as much as the formers. Therefore, one would
expect a gradient in the composition of the ISM between 6 and 12kpc
from the Galactic Centre, especially in its dust component. Most of
the replenishment (>50%) by AGB stars is due to sources with mass-loss
rate larger than 10-6M☉/yr.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 51 126 Properties of the 126 selected mass-losing
AGB sources
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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- 3 I3 --- [LMW2001] Sequential number
5- 14 A10 --- IRAS IRAS name
16- 20 F5.2 mag [2.20] The [2.20] magnitude (1)
22- 25 F4.2 mag [2.20-3.77] The [2.20-3.77] colour index (1)
27- 30 I4 pc DSun Distance to the sun
32- 36 I5 pc z Distance above the Galactic plane
38- 42 F5.2 kpc DGC Distance to the Galactic Center
44- 49 F6.3 [10-6solMass/yr] log(dM/dt) Mass-loss rate
51 A1 --- Comp [OC] Composition (2)
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Note (1): The magnitudes and colours are corrected for reddening.
[2.20] is the flux at 2.20µm, [3.77] the flux at 3.77µm.
Note (2): (C) stands for a carbon-rich composition and (O), for an oxygen-rich
composition.
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History:
From electronic version of the journal
(End) James Marcout, Patricia Bauer [CDS] 11-Oct-2001