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arXiv · 0909.2642

Near-IR spectra of IPHAS extremely red Galactic AGB stars

N. J. Wright·M. J. Barlow·R. Greimel·J. E. Drew·M. Matsuura·Y. C. Unruh·A. A. Zijlstra
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Abstract

We present a library of 139 near-IR spectra of cool asymptotic giant branch stars that will be useful for comparison with theoretical model atmosphere calculations and for modeling the integrated emission from intermediate-age stellar populations. The source list was selected from the `extremely red' region of the INT Photometric H Alpha Survey (IPHAS) colour-colour plane that is overwhelmingly dominated by very late-type stars. The spectral library also includes a large fraction of S-type and carbon stars. We present a number of spectral classification sequences highlighting the various molecular features identified and discuss a number of rare features with uncertain identifications in the literature. With its focus on particularly cool photospheres this catalogue serves as a companion to recent spectroscopic atlases of MK standards in the near-IR. Finally the relationship between IPHAS (r'-i') and (r'-H Alpha) colours and spectroscopically determined properties is discussed and a strong correlation between (r'-H Alpha) colour and the C/O abundance index for S-type and carbon stars is noted. This relation has the potential to separate O-rich, S-type and carbon stars in the Galaxy based on their photometry alone.

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N. J. Wright, M. J. Barlow, R. Greimel, J. E. Drew, M. Matsuura, Y. C. Unruh, A. A. Zijlstra. 2009-09-14. Near-IR spectra of IPHAS extremely red Galactic AGB stars. https://doi.org/10.1111/j.1365-2966.2009.15536.x

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