Betelgeuse Fainter in the Submillimeter Too: An Analysis of JCMT and APEX Monitoring during the Recent Optical Minimum
Abstract
Betelgeuse, the nearest red supergiant star to Earth, underwent an unusually deep minimum at optical wavelengths during its most recent pulsation cycle. We present submillimeter observations taken by the James Clerk Maxwell Telescope and Atacama Pathfinder Experiment over a time span of 13 yr including the optical dimming. We find that Betelgeuse has also dimmed by ∼20% at these longer wavelengths during this optical minimum. Using radiative-transfer models, we show that this is likely due to changes in the photosphere (luminosity) of the star as opposed to the surrounding dust, as was previously suggested in the literature.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 2020
- DOI:
- 10.3847/2041-8213/ab9ca6
- arXiv:
- arXiv:2006.09409
- Bibcode:
- 2020ApJ...897L...9D
- Keywords:
-
- Red supergiant stars;
- Submillimeter astronomy;
- Variable stars;
- Time domain astronomy;
- 1375;
- 1647;
- 1761;
- 2109;
- Astrophysics - Solar and Stellar Astrophysics;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- Accepted for publication in ApJ Letters June 14th 2020, 7 pages, 3 figures, 2 tables