Imaging Spectroscopy of a Solar Filament Using a Tunable Hα Filter

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

6

Scientific paper

Observations using a narrow band Hα filter still remain one of the best ways to investigate the fine structures and internal dynamics of solar filaments. Hα observations, however, have been usually carried out with the peak response of the filter fixed at a single wavelength, usually at the centerline, in which the investigation is limited to the Hα morphology and its time evolution. In this paper, we demonstrate that the Hα spectroscopy that takes Hα images successively at several wavelengths is a useful tool in the study of solar filaments on the solar disk. Our observation of a filament was carried out on August 3, 2004 at Big Bear Solar Observatory using the 10-inch refractor. The Lyot Hα filter was successively tuned to five wavelengths: -0.6, -0.3, 0.0, +0.3, and +0.6 Å from the Hα line center. Each set of wavelength scan took 15 s. After several steps of data reduction, we have constructed a five-wavelength spectral profile of intensity contrast at every spatial point. The contrast profile at each spatial point inside the filament was reasonably well fit by the cloud model as far as the contrast is high enough, and allowed us to construct the maps of τ0, v, Δ λD and S in the filament. We also found that the line center method that is often used, always yields line-of-sight velocities that are systematically lower than the cloud model fit. Our result suggests that taking Hα images at several wavelengths using a tunable filter provides an effective way of deriving physically meaningful parameters of solar filaments. Particularly constructing the time sequence of v maps appears to be a useful tool for the study of internal dynamics, like counterstreaming, in filaments.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Imaging Spectroscopy of a Solar Filament Using a Tunable Hα Filter does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Imaging Spectroscopy of a Solar Filament Using a Tunable Hα Filter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Imaging Spectroscopy of a Solar Filament Using a Tunable Hα Filter will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-983620

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.