Other
Scientific paper
Oct 1999
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1999esasp.446..519o&link_type=abstract
8th SOHO Workshop: Plasma Dynamics and Diagnostics in the Solar Transition Region and Corona. Proceedings of the Conference hel
Other
Scientific paper
In this paper we present results of an emission measure analysis performed on regions of cell, network and bright network emission which were observed in the quiet Sun at Sun centre with the Coronal Diagnostic Spectrometer (CDS) on board SOHO. Seperate emission from the three regions was obtained by a method of image segmentation using a histogram modification technique. From the averaged emission it was possible to produce emission measures over a broad temperature range. These emission measures were then used to produce estimates of radiative and conductive losses in the three regions considered. Using a magnetogram obtained from the MDI instrument on SOHO we show that the bright network emission originates from bipolar magnetic loops and from what appear to be monopole regions, which could be the remains of footpoints of larger loops. The bright network emission shows significantly higher mean magnetic field strength as well as significantly larger radiative energy losses than either of the other two regions. We find some evidence suggesting the presence of cool loops. The process of image segmentation also enabled us to obtain the relative areas of the cell, network and bright network emission as a function of temperature. We found that only the bright network emission showed an expansion in area with temperature and therefore height. Fitting this area curve with the functional form suggested by Rabin (1991),i.e A(T)/A(Th) = [1 + (Gamma2 - 1)(T/Th)nu]1/2/Gamma , for the cross-sectional area of a flux tube, we obtain a value of Gamma=7.1 and nu=2.5 for the constriction and shape factors respectively.
Gallagher Peter. T.
Keenan Francis P.
Mathioudakis Michail
O'Shea Edwin
Phillips Kenneth J. H.
No associations
LandOfFree
A New Study of the Quiet Sun 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 A New Study of the Quiet Sun, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A New Study of the Quiet Sun will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1084938