Sub-THz and Hα activity during the preflare and main phases of a GOES class M2 event

Kaufmann P.; Marcon R.; Gimenez De Castro C.G.; White S.M.; Raulin J.-P.; Correia E.; Fernandes L.O.; De Souza R.V.; Godoy R.; Marun A.; Pereyra P.

Sub-THz and Hα activity during the preflare and main phases of a GOES class M2 event

Tipo

Artigo

Data de publicação

2011

Periódico

Astrophysical Journal

Citações (Scopus)

6

Autores

Kaufmann P.
Marcon R.
Gimenez De Castro C.G.
White S.M.
Raulin J.-P.
Correia E.
Fernandes L.O.
De Souza R.V.
Godoy R.
Marun A.
Pereyra P.

Resumo

Radio and optical observations of the evolution of flare-associated phenomena have shown an initial and rapid burst at 0.4THz only followed subsequently by a localized chromospheric heating producing an Hα brightening with later heating of the whole active region. A major instability occurred several minutes later producing one impulsive burst at microwaves only, associated with an M2.0 GOES X-ray flare that exhibited the main Hα brightening at the same site as the first flash. The possible association between long-enduring time profiles at soft X-rays, microwaves, Hα, and sub-THz wavelengths is discussed. In the decay phase, the Hα movie shows a disrupting magnetic arch structure ejecting dark, presumably chromospheric, material upward. The time sequence of events suggests genuine interdependent and possibly non-thermal instabilities triggering phenomena, with concurrent active region plasma heating and material ejection. © 2011. The American Astronomical Society. All rights reserved.