Resumo

NESCI, R. et al. AGB Candidates in the field of γ CAS. Rev. mex. astron. astrofis [online]. 2018, vol.54, n.2, pp.341-354. ISSN 0185-1101.

We report the spectroscopic and photometric monitoring of a sample of 530 candidate AGB stars in a 5 × 5 degrees field, selected from the IPHAS catalog; historic light curves were derived from Asiago IR plates taken in the years 1965 -1984. We found 10 Miras, 5 stars with long term trends, 3 semiregular and 3 irregular. Spectral types from CCD slit spectra gave 8 M-type, 7 C-type and 6 S-type stars. In the color-color plots made from IPHAS and 2MASS catalogs, the S-type and M-type stars occupy the same regions, while C-type stars are well separated. All C-type stars with IR excess show long term trends in their light curve. Distances of the Mira stars, estimated from their periods and K magnitudes, give a median value 4.9 kpc with a large spread. A comparison with astrometric parallaxes from Gaia DR2 is briefly discussed.

Palavras-chave : stars: AGB and post-AGB; stars: late-type; stars: variables: general.

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