Local Group AGB stars and red supergiants

Pulsation periods are derived for a large fraction of the sample based on a re-analysis of existing data. New deep K-band photometry from the VMC survey and multi-epoch data from IRAC (at 4.5 micron) and AllWISE and NEOWISE have allowed us to derive pulsation periods longer than 1000 days for some of the most heavily obscured and reddened objects. We derive (dust) MLRs and luminosities for the entire sample.

The estimated MLRs can differ significantly from estimates for the same objects in the literature due to differences in adopted optical constants (up to factors of several) and details in the radiative transfer modelling. Updated parameters for the super-AGB candidate MSX SMC 055 (IRAS 00483-7347) are presented. Its current mass is estimated to be 8.5 +- 1.6 solar mass, suggesting an initial mass well above 8 solar mass in agreement with estimates based on its large Rubidium abundance.

Using synthetic photometry, we present and discuss color-color and color-magnitude diagrams which can be expected from the James Webb Space Telescope.