On the Origin of Pulsations of Sub-THz Emission from Solar Flares

Author(s)

Zaitsev, V. V. ^[1] ; Stepanov, A. V. ^[2] ; Kaufmann, P. ^[3]

Affiliation

^[1] Inst Appl Phys, Nizhnii Novgorod 603950 - Russia

^[2] Pulkovo Observ, St Petersburg 196140 - Russia

^[3] Uniersidade Presbiteriana Mackenzie, Escola Engn, Ctr Radioastron & Astrofis Mackenzie, BR-01302907 Sao Paulo - Brazil

• Document type: Journal article
• Source: SOLAR PHYSICS; v. 289, n. 8, p. 3017-3032, AUG 2014.
• Web of Science Citations: 10

Abstract

We propose a model to explain fast pulsations in sub-THz emission from solar flares. The model is based on the approach of a flaring loop as an equivalent electric circuit and explains the pulse-repetition rate, the high-quality factor, Qa parts per thousand yen10(3), low modulation depth, pulse synchronism at different frequencies, and the dependence of the pulse-repetition rate on the emission flux, observed by Kaufmann et al. (Astrophys. J. 697, 420, 2009). We solved the nonlinear equation for electric current oscillations using a Van der Pol method and found the steady-state value for the amplitude of the current oscillations. Using the pulse rate variation during the flare on 4 November 2003, we found a decrease of the electric current from 1.7x10(12) A in the flare maximum to 4x10(10) A just after the burst. Our model is consistent with the plasma mechanism of sub-THz emission suggested recently by Zaitsev, Stepanov, and Melnikov (Astron. Lett. 39, 650, 2013). (AU)

• FAPESP's process: 06/06847-1 - Solar activity emissions from submillimeter waves to infrared (SIRA)
• Grantee: Pierre Kaufmann
• Support type: Research Projects - Thematic Grants