It is shown that if a thin, isolated and untwisted magnetic flux tube, consisting of a current-free core bounded by a thin current sheath, is in an ‘overall’ equilibrium in a stratified atmosphere, then there is, in general, ...

The equilibrium and stability of a loop in which energy storage occurs prior to a solar flare is discussed. Working on the hypothesis, that the onset of the flare begins only after sufficient magnetic energy has been stored ...