Diameters of Miras and Red Giants Measured by Narrow Bandwidth Mid-IR Interferometry
Abstract
A straight-forward measurement of the diameters of giant stars is, in general, difficult. The diffuse nature of the surrounding stellar atmosphere and the presence of spectral lines as well as circumstellar dust can cause the apparent diameters to differ substantially from the actual photospheric diameter. Using the two-telescope ISI interferometer, with its narrow band heterodyne detection system, we were able to measure stellar diameters at 11.15um, avoiding strong spectral lines and minimizing the errors due to limb darkening. In addition, the mid-infrared spectrum of these stars was observed so that any change in the measured diameter due to spectral lines could be estimated. This change, typically, will be less than 2
- Publication:
-
American Astronomical Society Meeting Abstracts #198
- Pub Date:
- May 2001
- Bibcode:
- 2001AAS...198.2202W