April 2017 – Community of European Solar Radio Astronomers

The Brightness Temperature of the Quiet Solar Chromosphere at 2.6 mm
by Kazumasa Iwai et al

2017-04-25 1,031 views

The brightness temperature of the Sun constitutes a basic property of the solar atmosphere. The main emission mechanism of the Sun at millimeter and submillimeter wavelengths is thermal free–free emission from the chromosphere, which is an atmospheric layer with a temperature ranging between 6000 to 20,000 K. The opacity of thermal free–free emission depends on the temperature and density in the emission region. In addition, the Rayleigh– Jeans law is applicable […]

How Electron Beams Produce Continuous Coherent Plasma Emission
by H. Che, M. Goldstein, P. Diamond, and R. Sagdeev

2017-04-11 923 views

It is commonly accepted that energetic electron beams can produce drift frequency radio emission or Type III bursts since Ginzburg and Zhelezniakov first proposed the idea in 1958. However, the electron two-stream instability time (see reference 2) in the corona is fraction of a second, while the duration of coronal Type III bursts lasts several orders of magnitude longer. This problem is called the “Sturrock Dilemma” and remains a subject […]