Angular Diameter Measurements of Evolved Variables by Lunar Occultations at 2.2 and 3.8 Μm
نویسندگان
چکیده
We report the angular diameters of two Mira variables (U Ari and Z Sco), three semi-regular and irregular variables (SW Vir, η Gem and µ Gem) and a supergiant semi-regular variable (TV Gem) by lunar occultation observations in the near-infrared broad K-band (2.2 µm). Lunar occultations of η Gem and µ Gem were also observed for the first time simultaneously in both K and L ′ bands yielding angular diameters at 2.2 and 3.8 µm. Effective temperatures and linear radii are also derived for all the observed sources and compared with earlier measurements. The mode of pulsation of both Mira and SR sources in our sample is discussed.
منابع مشابه
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