Observations of Coronal Structures Above an Active Region by EIT and Implications for Coronal Energy Deposition

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

40

Scientific paper

Solar EUV images recorded by the EUV Imaging Telescope (EIT) on SOHO have been used to evaluate temperature and density as a function of position in two largescale features in the corona observed in the temperature range of 1.0-2.0MK. Such observations permit estimates of longitudinal temperature gradients (if present) in the corona and, consequently, estimates of thermal conduction and radiative losses as a function of position in the features. We examine two relatively cool features as recorded in EIT's Feix/x (171Å) and Fexii (195Å) bands in a decaying active region. The first is a long-lived loop-like feature with one leg, ending in the active region, much more prominent than one or more distant footpoints assumed to be rooted in regions of weakly enhanced field. The other is a near-radial feature, observed at the West limb, which may be either the base of a very high loop or the base of a helmet streamer. We evaluate energy requirements to support a steady-state energy balance in these features and find in both instances that downward thermal conductive losses (at heights above the transition region) are inadequate to support local radiative losses, which are the predominant loss mechanism. The requirement that a coronal energy deposition rate proportional to the square of the ambient electron density (or pressure) is present in these cool coronal features provides an additional constraint on coronal heating mechanisms.

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

Observations of Coronal Structures Above an Active Region by EIT and Implications for Coronal Energy Deposition 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 Observations of Coronal Structures Above an Active Region by EIT and Implications for Coronal Energy Deposition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observations of Coronal Structures Above an Active Region by EIT and Implications for Coronal Energy Deposition will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-765733

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