submillimeter emission

New Instrument in Solar Flare Detection: A 50–55 GHz Millimeter-Wave Radiometer Spectrometer by X. Xu et al.

November 25, 2025

Solar flares, among the most intense explosive phenomena in the solar atmosphere, release vast amounts of energy in a short period, resulting in enhanced electromagnetic radiation across multiple bands. These events pose significant threats to Earth’s space environment and human activities in space. High-energy electrons accelerated during flares emit millimeter-wave radiation through gyrosynchrotron radiation, providing unique insights into the underlying magnetic fields and energy release processes (Fleishman et al 2018). […]

Two-element interferometer for millimeter-wave solar flare observations, by Yu et al.

August 29, 2023

Solar radio emission can be significantly influenced by Earth’s atmosphere when transmitting towards the Earth’s surface, due to atmospheric turbulence and the absorption of vapor and oxygen molecules etc. Consequently, antennas receive signals with a ‘dither’ component, indicating a noise signal exhibiting random variations. As a result, the sensitivity of observing systems distorts severely , especially for weaker radio bursts in the millimeter passband. Weak bursts can be usually observed […]

Simultaneous Submillimeter and Hard X-Ray Intermittent Processes during Flares by Guillermo Giménez de Castro et al.*

November 29, 2016

Intermittency is a disruptive characteristic of a process, which can be associated, in many cases, with a sudden energy release. Intermittency is a key characteristic of flares that should become evident in the flux time evolution at many different wavelengths. We investigate the similarities and differences of the intermittency during a solar flare in bremsstrahlung hard X-rays and synchrotron+free-free submillimeter emission. For this we chose a particular event that presents […]

On the thermal nature of 140 GHz emission from the 4 July 2012 solar flare by Yuriy Tsap et al.*

August 30, 2016

The nature of the solar flare sub-THz emission (Kaufmann, 2012) with a positive spectral slope at 200-400 GHz is still not clear [see also previous CESRA highlight]. Some authors associate this emission with thermal bremsstrahlung, while other suggest it is associated with different, non-thermal mechanisms (see Fleishman & Kontar, 2010; Krucker et al., 2013). There are two serious disadvantages of the existing approaches. First, there is a lack of observations in […]

Bright 30 THz impulsive solar bursts by Pierre Kaufmann et al.*

August 23, 2016

Impulsive 30 THz continuum bursts have been recently observed in solar flares, utilizing small telescopes with a unique and relatively simple optical setup concept (Kaufmann et al. 2015). The most intense burst was observed together with a GOES X2 class event on October 27, 2014, also detected at two sub-THz frequencies, RHESSI X-rays and SDO/HMI and EUV. It exhibits strikingly good correlation in time and in space with white light […]