Betelgeuse Fainter in the Submillimeter Too: An Analysis of JCMT and APEX Monitoring during the Recent Optical Minimum

@article{Dharmawardena2020BetelgeuseFI,
  title={Betelgeuse Fainter in the Submillimeter Too: An Analysis of JCMT and APEX Monitoring during the Recent Optical Minimum},
  author={Thavisha E Dharmawardena and Steve Mairs and Peter Scicluna and Graham S. Bell and Iain McDonald and Karl M. Menten and Axel Weiss and Albert A. Zijlstra},
  journal={arXiv: Solar and Stellar Astrophysics},
  year={2020}
}
Betelgeuse is the nearest Red Supergiant star and it underwent an unusually deep minimum at optical wavelengths during its most recent pulsation cycle. We present submillimetre observations taken by the James Clerk Maxwell Telescope and Atacama Pathfinder Experiment over a time span of 13 years including the optical dimming. We find that Betelgeuse has also dimmed by \sim20\% at these longer wavelengths during this optical minimum. Using radiative-transfer models, we show that this is likely… 

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