The Schumann resonances

Abstract

con s id e red d irectly as a ca vit y probl e m ra th er than as a limitin g case of propaga tion in a qua si-waveguid e with a n a rbitra ry (s ph e ri c a ll y sy mm e tri c) co ndu ctivity profil e. By u sing an approx im ation to a th c oreti ca ll y de rived prof ti e, va lu es fur the frequ encies and Q fac to rs of th e lowe r resona nces are computed whi c h compare with ex perim e ntal res ult s as we ll as or be tte r than th e valu es de ri ved fro m pre violl s mode ls.