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arXiv · 2202.12434

First High Resolution Interferometric Observation of a Solar Prominence With ALMA

Nicolas Labrosse·Andrew S. Rodger·Krzysztof Radziszewski·Paweł Rudawy·Patrick Antolin·Lyndsay Fletcher·Peter J. Levens·Aaron W. Peat·Brigitte Schmieder·Paulo J. A. Simões
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Abstract

We present the first observation of a solar prominence at $84-116$ GHz using the high resolution interferometric imaging of ALMA. Simultaneous observations in H$\alpha$ from Bia{\l}kaw Observatory and with SDO/AIA reveal similar prominence morphology to the ALMA observation. The contribution functions of 3 mm and H$\alpha$ emission are shown to have significant overlap across a range of gas pressures. We estimate the maximum millimetre-continuum optical thickness to be $\tau_\mathrm{3mm}\approx 2$, and the brightness temperature from the observed H$\alpha$ intensity. The brightness temperature measured by ALMA is $\sim 6000-7000$ K in the prominence spine, which correlates well with the estimated brightness temperature for a gas temperature of 8000 K.

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Nicolas Labrosse, Andrew S. Rodger, Krzysztof Radziszewski, Paweł Rudawy, Patrick Antolin, Lyndsay Fletcher, Peter J. Levens, Aaron W. Peat, Brigitte Schmieder, Paulo J. A. Simões. 2022-02-25. First High Resolution Interferometric Observation of a Solar Prominence With ALMA. https://doi.org/10.1093/mnrasl/slac021

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