Multi-wavelength observations of filament oscillations induced by shock waves

Two cases of filament oscillations induced by large-scale coronal shock waves are presented. For the first case, a chain of transverse oscillating filaments are observed in a proper order after the passing of a shock wave, and it is found that the they were triggered by the surface component of the dome-shaped shock wave. For the second case, simultaneous transverse oscillation of a limb prominence and longitudinal oscillation in an on-disk filament are launched by a single shock wave. It is found that the interaction angle between the shock wave and the prominence axis is the key to launch transverse or longitudinal filament oscillations. In addition, filament magnetic fields are estimated, using the measured parameters.

The Observation and Study of Two Prominence Events in the Infrared

This paper reports the first extremely near infrared observation of two prominence events on Jan. 8, 1999 and Feb. 9, 1999 at H Pfund β (46525Å) and H Bracket α (40512Å) using the McMath Telescope. We scanned the spectrograph slit across the prominences parallel to the limb to obtain three-dimensional data cubes (two spatial dimensions and one spectral dimension). By fitting these observed lines, we can directly determine some important physical parameters such as Doppler width (ΔλD), the optical thickness at line center (τΔ0), and the line displacement (Δλ0). Combined with simultaneous observation of Balmer Hα, Hβ, and Ca K lines, the new results of structure and dynamics of limb prominence is presented. These results imply that these infrared lines can penetrate through the prominence and become a potential probe and tool, while Hα and Hβ sense the prominence skin only.