Issue |
Astron. Astrophys. Suppl. Ser.
Volume 118, Number 3, September 1996
|
|
---|---|---|
Page(s) | 397 - 405 | |
DOI | https://doi.org/10.1051/aas:1996207 | |
Published online | 15 September 1996 |
Irregular variables of type Lb. New JHKL'M-photometry for 160 stars*
1
Institut für Astronomie der Universität Wien, Türkenschanzstraße 17, A-1180 Wien, Austria
2
Dpto. de Astrofísica, Fac. de Física, Universidad de La Laguna, 38200-La Laguna, Tenerife, Spain
3
Instituto de Astrofísica de Canarias, 38200-La Laguna, Tenerife, Spain
Corresponding author: Send offprint request to: e-mail: kerschbaum@astro.ast.univie.ac.at
Received:
16
August
1996
Accepted:
10
January
1996
This paper presents new near infrared observations of
160 Irregular variables of type Lb in the
filter bands. These measurements are supplemented by data
for additional 56 stars taken from the
literature. In total 220 datasets are available because of
some multiple observations. From our sample, 216 stars
have near infrared (NIR) photometry now.
Our sample of visually bright Lb-variables displays
very similar infrared properties when compared with SRa-
and SRb-variables. Derived from NIR-two colour diagrams
the oxygen-rich Lbs seem to have intermediate
atmospheric conditions between Miras and normal giants.
There may be a sligthly larger “contamination” with non AGB-giants
than in the case of the semiregulars. Using only our
IR-colours the S- and the Carbon-stars among the Lbs
again are undistinguishable from SR-variables of the same
chemistry.
Key words: stars: asymptotic giant branch (AGB) / stars: variables / stars: mass-loss / infrared: stars
© European Southern Observatory (ESO), 1996