- ... AGB stars
- Based
on observations at the 4.2 m William Herschel Telescope operated on the island of
La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de Los
Muchachos of the Instituto de Astrofisica de Canarias. Also based on
observations with the ESO 3.6 m telescope at La Silla Observatory
(Chile).
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...
- Tables 1-9 are only available in electronic form at http://www.aanda.org
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ... Survey
- The Digitized Sky Survey was
produced at the Space Telescope Science Institute under US Government grant
NAG W-2166.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ... [60]
- Defined as
[12] - [25] = -2.5 log(F12/F25) and [25]-[60] = -2.5
log(F25/F60), where F12, F25 and F60 are the IRAS flux
densities at 12, 25 and 60
m, respectively.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ... SIMBAD
- Set of
Identifications, Measurements, and Bibliography for Astronomical Data, operated
at CDS, Strasbourg, France.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ... IRAF
- Image Reduction and Analysis Facility
(IRAF) software is distributed by the National Optical Astronomy Observatories,
which is operated by the Association of Universities for Research in Astronomy,
Inc., under cooperative agreement with the National Science Foundation.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ... stars
- In contrast, the spectra of the few C-rich AGB stars found
in our spectroscopic survey (see list in Table 3) are dominated by CN and
C2 absorption bands.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ... NIST
- National Institute of Standards and
Technology (NIST); http://physics.nist.gov/cgi-bin/AtData/lines_form.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ... vii) log
(Zr)
- The zirconium abundance is given in the usual scale
12 + log N(Zr). On this scale the solar zirconium abundance is 2.6 dex.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ...1990b)
- This is the only other chemical analysis previously carried out
in Galactic O-rich AGB M-type stars (only six stars!) before the work presented
here. However, these were low-mass stars (
)
and
their study was focussed on the determination of CNO abundances through near-IR
spectra and the s-process enrichment, but they did not study the lithium
enrichment in particular.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
- ... Galaxy
- Note that, in addition, AGB stars are also strongly variable. As an example, Engels et al. (1983) found an
variation of 2 mag between the minimum and maximum light (from -5.0 to -7.1 mag respectively) in the Galactic OH/IR star OH 32.8-0.3.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.