Bibcode
Karpen, J. T.; Luna, M.; Knizhnik, Kalman J.; Muglach, Karin; Gilbert, Holly; Kucera, Therese A.; Uritsky, Vadim
Referencia bibliográfica
American Astronomical Society, AAS Meeting #224, #111.06
Fecha de publicación:
6
2014
Número de citas
0
Número de citas referidas
0
Descripción
On 20 August 2010 an energetic disturbance triggered large-amplitude
longitudinal oscillations in a large fraction of a nearby filament. The
triggering mechanism appears to be episodic jets connecting the
energetic event with the filament threads. We analyzed this periodic
motion to characterize the underlying physics of the oscillation as well
as the filament properties. The results support our previous theoretical
conclusions that the restoring force of large-amplitude longitudinal
oscillations is solar gravity, and the damping mechanism is the ongoing
accumulation of mass onto the oscillating threads. Based on our previous
work, we used the fitted parameters to determine the magnitude and
radius of curvature of the dipped magnetic field along the filament, as
well as the mass accretion rate onto the filament threads. These derived
properties are nearly uniform along the filament, indicating a
remarkable degree of homogeneity throughout the filament channel.
Moreover, the estimated mass accretion rate implies that the footpoint
heating responsible for the thread formation, according to the thermal
nonequilibrium model, agrees with previous coronal heating estimates. We
also estimated the magnitude of the energy released in the nearby event
by studying the dynamic response of the filament threads, and concluded
that the initiating event is likely to be a microflare. We will present
the results of this investigation and discuss their implications for
filament structure and heating. This work was supported by NASA’s
H-SR program.