Mona J. Hagyard

TL;DR: In this paper, a quantitative evaluation of the shear in the magnetic field along the neutral line in an active region during an epoch of flare activity is presented, and it is suggested that continued magnetic evolution causes the field's maximum shear to exceed a critical value of shear, resulting in a flare around the site of maximum shears.

TL;DR: In this article, the authors discuss the total transformation of specific vector magnetograms to detail the problems and procedures that one should be aware of in analyzing observational magnetograms and the effect of the 180-deg ambiguity of the observed transverse field is considered.

TL;DR: In this article, the evolution of vector photospheric magnetic fields has been studied in concert with photosphere spot motions for a flare-productive active region over a three-day period (5-7 April, 1980).

TL;DR: In this paper, it was shown that flaring activity as seen in X-rays usually encompasses two or more interacting magnetic bipoles within an active region, and that the basic structure of a flare usually consists of an initiating closed bipole plus one or more adjacent closed bipoles impacted against it.

TL;DR: The NASA/Marshall Space Flight Center's solar vector magnetograph system is described in this article, which allows measurements of all components of the Sun's photospheric magnetic field over a 5 × 5 or 2.0×2.0 arc min square field-of-view with an optimum time resolution of ∼ 100 s and an optimum signal to noise of ∼ 1600.