A Study of Whistlers Observed at Agra

Abstract

Results of whistler observations during the period Jan-July 1979 at the low latitude ground station of Bichpuri, Agra (geomag. lat., 17° 12') are presented and some unusual characteristics such as high dispersion and lower cut-off frequency below the waveguide cut-off frequency are explained. To explain the propagation characteristics of these whistlers in the low latitude ionosphere, calculations of enhancement factors in the ducts along the field lines corresponding to different low <i>L </i> values are carried out. The results show that suitable ducts are not formed below <i>L </i> = 1.7 and hence the low latitude whistlers are propagated mostly in non-ducted mode.