AGB stars and the plate archives heritage

TL;DR

This paper characterizes AGB candidate stars using historical photographic plates, modern CCD data, and spectral classification, enhancing methods to distinguish variable stars and spectral types for larger stellar samples.

Contribution

It introduces an integrated approach combining archival plates, CCD photometry, and spectral data to improve classification and selection of AGB stars.

Findings

Successful identification of AGB candidates using multiple data sources.

Effective spectral classification into C-Type, N-Type, and M giants.

Color-color plots enable efficient spectral type discrimination.

Abstract

We report on the characterization of a number of AGB candidate stars identified with objective-prism plates of the Byurakan Observatory. Digitized photographic sky survey plates and recent CCD photometry have been used to improve the selection and distinguish variable and non-variable stars. Some comparisons among published catalog magnitudes are also made. Slit spectroscopy from the Asiago and Loiano Observatories allowed a firm spectral classification, separating C-Type, N-Type and normal M giants. Color-color plots using WISE, AKARI and 2MASS J-band data allow an efficient discrimination of spectral types, which can be used for the definition of larger statistical samples.