The Inability of Steady-Flow Models to Explain the Extreme-Ultraviolet Coronal Loops

Details The Inability of Steady-Flow Models to Explain the Extreme-Ultraviolet Coronal Loops The Inability of Steady-Flow Models to Explain the Extreme-Ultraviolet Coronal Loops

Mar 2004

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004apj...603..322p&link_type=abstract

The Astrophysical Journal, Volume 603, Issue 1, pp. 322-329.

Astronomy and Astrophysics

Astronomy

37

Hydrodynamics, Sun: Corona, Sun: Uv Radiation

Scientific paper

Recent observations from the Transition Region and Coronal Explorer (TRACE) and the EUV Imaging Telescope (EIT) show that warm (T~1-1.5 MK) EUV coronal loops in active regions generally have enhanced densities, enhanced pressure scale heights, and flat filter ratio (temperature) profiles in comparison with the predictions of static-equilibrium theory. It has been suggested that mass flows may explain these discrepancies. We investigate this conjecture using one-dimensional hydrodynamic simulations of steady flows in coronal loops. The flows are driven by asymmetric heating that decreases exponentially along the loop from one footpoint to the other. We find that a sufficiently large heating asymmetry can produce density enhancements consistent with a sizable fraction of the observed loops, but that the pressure scale heights are smaller than the corresponding gravitational scale heights, and that the filter ratio profiles are highly structured, in stark contrast to the observations. We conclude that most warm EUV loops cannot be explained by steady flows. It is thus likely that the heating in these loops is time dependent.

Affiliated with

Also associated with

No associations

Rating

The Inability of Steady-Flow Models to Explain the Extreme-Ultraviolet Coronal Loops 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 The Inability of Steady-Flow Models to Explain the Extreme-Ultraviolet Coronal Loops, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Inability of Steady-Flow Models to Explain the Extreme-Ultraviolet Coronal Loops will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1621007