INVESTIGADORES
MANDRINI Cristina Hemilse
artículos
Título:
Origin of the Submillimeter Radio Emission During the Time-Extended Phase of a Solar Flare
Autor/es:
TROTTET, G.; RAULIN, J.P; GIMÉNEZ DE CASTRO, C.G.; LUTHI, T.; CASPI, A.; MANDRINI, C.H.; LUONI, M.L.; KAUFMANN, P.
Revista:
SOLAR PHYSICS
Editorial:
SPRINGER
Referencias:
Lugar: Berlín; Año: 2011 vol. 273 p. 339 - 361
ISSN:
0038-0938
Resumen:
Solar flares observed in the 200 - 400 GHz radio domain may exhibit a
slowly varying and time-extended component which follows a short (few
minutes) impulsive phase and can last for a few tens of minutes to more
than one hour. The few examples discussed in the literature indicate
that such long-lasting submillimeter emission is most likely thermal
bremsstrahlung. We present a detailed analysis of the time-extended
phase of the 27 October 2003 (M6.7) flare, combining 1 - 345 GHz
total-flux radio measurements with X-ray, EUV, and Há
observations. We find that the time-extended radio emission is, as
expected, radiated by thermal bremsstrahlung. Up to 230 GHz, it is
entirely produced in the corona by hot and cool materials at 7 - 16 MK
and 1 - 3 MK, respectively. At 345 GHz, there is an additional
contribution from chromospheric material at a few 10000 K.
These results, which may also apply to other millimeter-submillimeter
radio events, are not consistent with the expectations from standard
semiempirical models of the chromosphere and transition region during
flares, which predict observable radio emission from the chromosphere at
all frequencies where the corona is transparent.
all frequencies where the corona is transparent.