The Density of Coronal Null Points from Hinode and MDI
Solar and Stellar Astrophysics
2009-01-21 v1
Abstract
Magnetic null points can be located numerically in a potential field extrapolation or their average density can be estimated from the Fourier spectrum of a magnetogram. We use both methods to compute the null point density from a quiet Sun magnetogram made with Hinode's NFI and from magnetograms from SOHO's MDI in both its high-resolution and low-resolution modes. All estimates of the super-chromospheric column density (z>1.5 Mm) agree with one another and with the previous measurements: 0.003 null points per square Mm of solar surface.
Keywords
Cite
@article{arxiv.0901.0865,
title = {The Density of Coronal Null Points from Hinode and MDI},
author = {Dana Longcope and Clare Parnell and Craig DeForest},
journal= {arXiv preprint arXiv:0901.0865},
year = {2009}
}