000002315 001__ 2315
000002315 005__ 20160701171703.0
000002315 0247_ $$2DOI$$a10.1051/0004-6361/200911675
000002315 037__ $$aASTROimport-472
000002315 100__ $$aGroenewegen, M. A. T.
000002315 245__ $$aNear-infrared spectroscopy of AGB star candidates in Fornax, Sculptor, and NGC 6822
000002315 260__ $$c2009
000002315 520__ $$aContext: The asymptotic giant branch (AGB) phase is characterised by substantial mass loss that is accompanied by the formation of dust. In extreme cases this will make the star no longer visible in the optical. For a better understanding of AGB evolution it is important to identify and characterise these very red AGB stars.  Aims: The first aim of this article is to improve the census of red AGB stars in three Local Group galaxies, based on near-IR spectroscopic observations of new candidates with red 2MASS (J-K) colours. The opportunity is taken to compare the near-IR spectra with those of Milky Way stars.  Methods: We used ISAAC on the ESO VLT to take J and H-band spectra of 36 targets in Fornax, Sculptor and NGC 6822.  Results: Twelve new C-stars are found in Fornax, and one is confirmed in Sculptor. All C-stars have (J-K) > 1.6, and are brighter than -3.55 in bolometric magnitude. Ten new oxygen-rich late-type giant stars are identified in Fornax, but none is extremely red or very luminous. Five luminous O-rich AGB stars are identified in NGC 6822, of which 3 show water absorption, indicative of spectral type M. Again, none is as red as Milky Way OH/IR stars, but in this galaxy the list of candidate AGB stars is biased against very red objects. In some C-stars with (J-K)>2 an extremely strong 1.53 µm absorption band is found. These stars are probably all Mira variables and the feature is related to the low temperature, high density chemistry that is a first step towards dust formation and mass loss. Based on observations collected at the European Southern Observatory, Paranal, Chile (ESO programme 75.D-0152). Figure 6 is only available in electronic form via  http://www.aanda.org 
000002315 700__ $$a Lançon, A.
000002315 700__ $$a Marescaux, M.
000002315 773__ $$c1031-1040$$i3$$pAstronomy and Astrophysics$$v504$$y2009
000002315 85642 $$ahttp://esoads.eso.org/abs/2009A%26A...504.1031G
000002315 905__ $$apublished in
000002315 980__ $$aREFERD