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Carbon-Rich Mira Variables: Kinematics and Absolute Magnitudes

Michael W. Feast·Patricia A. Whitelock·John W. Menzies
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Abstract

The kinematics of galactic C-Miras are discussed on the basis of the bolometric magnitudes and radial velocities of Papers I and II of this series. Differential galactic rotation is used to derive a zero-point for the bolometric period-luminosity relation which is in satisfactory agreement with that inferred from the LMC C-Miras. We find for the galactic Miras, Mbol = -2.54logP + 2.06 (+/- 0.24), where the slope is taken from the LMC. The mean velocity dispersion, together with the data of Nordstroem et al. and the Padova models, leads to a mean age for our sample of C-Miras of 1.8 +/- 0.4 Gyr and a mean initial mass of 1.8 +/-0.2 solar masses. Evidence for a variation of velocity dispersion with period is found, indicating a dependence of period on age and initial mass, the longer period stars being younger. We discuss the relation between the O- and C-Miras and also their relative numbers in different systems.

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Michael W. Feast, Patricia A. Whitelock, John W. Menzies. 2006-03-18. Carbon-Rich Mira Variables: Kinematics and Absolute Magnitudes. https://doi.org/10.1111/j.1365-2966.2006.10324.x

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