Research Note

Comparison of 30 THz impulsive burst time development to microwaves, Hα, EUV, and GOES soft X-rays

¹ Center of Radio Astronomy and Astrophysics, Engineering School, Mackenzie Presbyterian University, São Paulo, SP, Brazil
² Space Research and Technology Institute, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
e-mail: rmiteva@space.bas.bg
³ Center of Semiconductor Components, State University of Campinas, Campinas, SP, Brazil
⁴ Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304, USA
⁵ Astronomical Institute of the Academy of Sciences of the Czech Republic, 251 65 Ondřejov, Czech Republic
⁶ LESIA-Observatoire de Paris, 92190 Meudon, France
⁷ Instituto de Astronomía y Física del Espacio (IAFE), CONICET-UBA, Buenos Aires, Argentina
⁸ “Gleb Wataghin” Physics Institute, State University of Campinas, Campinas, SP, Brazil
⁹ “Bernard Lyot” Solar Observatory, Campinas, SP, Brazil
¹⁰ Air Force Research Laboratories, Space Vehicles Directorate, Albuquerque, NM 87117, USA

Received: 15 December 2014
Accepted: 20 November 2015

Abstract

The recent discovery of impulsive solar burst emission in the 30 THz band is raising new interpretation challenges. One event associated with a GOES M2 class flare has been observed simultaneously in microwaves, Hα, EUV, and soft X-ray bands. Although these new observations confirm some features found in the two prior known events, they exhibit time profile structure discrepancies between 30 THz, microwaves, and hard X-rays (as inferred from the Neupert effect). These results suggest a more complex relationship between 30 THz emission and radiation produced at other wavelength ranges. The multiple frequency emissions in the impulsive phase are likely to be produced at a common flaring site lower in the chromosphere. The 30 THz burst emission may be either part of a nonthermal radiation mechanism or due to the rapid thermal response to a beam of high-energy particles bombarding the dense solar atmosphere.