Recent Observations of Betelgeuse and New Instrumentation at the ISI
نویسندگان
چکیده
The Infrared Spatial Interferometer (ISI) has been conducting mid-infrared observations of late-type stars for about 18 years. A long-term set of diameter measurements of Betelgeuse at 11.15 μm shows pronounced changes in the stellar size over time. These changes may arise from variations in the opacity of the environment immediately surrounding the star. New instrumentation is being developed to identify the composition and kinematics of the circumstellar environment of Betelgeuse, and of other late-type stars. A digital spectrometer-correlator is being built and tested that will enable visibility measurements on-and-off individual molecular spectral lines. Results from testing the spectrometer system are presented.
منابع مشابه
Mid-infrared interferometry with high spectral resolution
The Infrared Spatial Interferometer (ISI) is a three telescope interferometer system that operates near 11 microns wavelength using heterodyne detection with CO2 lasers as local oscillators. Stellar measurements have been made using consistent instrumentation for 20 years, allowing comparisons of stellar sizes of red giant and Mira stars over time intervals which are long in comparison to stell...
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