Pre-impulsive flare energy release according to sub-terahertz and X-ray solar observations

Main Article Content

Viktoriya V. Smirnova
Yurii T. Tsap
Vladimir S. Ryzhov

Abstract

We study time delays between X-ray and sub-terahertz emission at the initial phase of solar flares to clarify the nature of heating of the transition region and upper chromosphere of the Sun. Analysis of a series of events showed that hard X-ray emission is delayed relative to sub-THz emission at the onset of flares by 3–6 minutes for some considered events. The electron thermal conductivity of the coronal plasma cannot ensure the effective heating of the transition region and solar chromosphere. This suggests the heating of the chromospheric plasma in situ during the pre-impulsive phase of solar flares.

Keywords: Sun, solar flares, sub-terahertz radio emission, chromosphere

Supporting Agencies

This work was supported by the RFBR grant No. 20-52-26006 Czech_a (V.V. Smirnova), the RSF grant No. 22-12-0030 (Yu.T. Tsap), and the Ministry of Education and Science research project No. 1021051101548-7- 1.3.8 (Yu.T. Tsap, V.V. Smirnova).

Article Details

Section

Magnetism and Activity of the Sun - 2022 Conference proceedings

How to Cite

Smirnova V.V., Tsap Y.T., Ryzhov V.S., 2024. Acta Astrophysica Taurica, vol. 5, no. 4, pp. 35–38. Available at: https://astrophysicatauricum.org/index.php/aat/article/view/93 (Accessed: 1 April 2026)

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