Abstract
A prominence eruption followed by a coronal brightening was
simultaneously observed in radio (17
GHz), soft X-rays, and H(alpha) on 1992 July 30-31. The observations
were performed by newly
developed high-performance instruments:
the Nobeyama Radioheliograph,
the SXT on the
Yohkoh satellite, the Flare Monitoring Telescope of the Hida
Observatory, and some other
H(alpha) telescopes. This event gives us a much more detailed picture of
this type of phenomena
than previously observed. The erupting prominence, which occurred in a
quiet region and was
observed in H(alpha) and radio, ascended with a velocity of about 100
km/sec. The general
structure of the erupting prominence seen at 17 GHz is very similar to
that at H(alpha). While the
prominence expanded rapidly, the total radio flux of the erupting
prominence did not change very
much. Since a prominence consists of fine threads, this fact means that
each thread did not expand
while the prominence expanded. Consequently, the surface filling factor
of the prominence must
have decreased during the eruption. The high-resolution pictures of a
clear coronal arcade
structure were taken in soft X-rays and radio after the prominence
eruption; the physical
parameters of the arcade were derived from these pictures. The mean
temperature was 3.5 x
10(exp 6) K in the early phase, and decreased to 2.6 x 10(exp 6) K
within seven hours. The total
emission measure reached a maximum value of(1.6 x 10(exp 48))/cu cm
after three hours from the
beginning of the arcade brightening, when the electron density at the
ridge of the arcade is
estimated as(2.4 x 10(exp 9))/cu cm. The temporal and spatial
relationship between the erupting
prominence and the coronal arcade is shown. It gives an observational
restriction to the magnetic
field configuration of the models of such events.