Sunspot Dependence of the Noon Bite-out Phenomenon of the F2 Region at Equatorial Latitudes

摘要: The effect of sunspot activity on the noon bite-out phenomenon is investigated for a number equatorial stations during period 1958–64. It-is well known that forenoon peak prominent maximum and afternoon minimum period. magnitudes two peaks are almost same certain this referred to as ‘Critical number’. It observed critical increases systematically with decreasing |L—I|, where L I geographic latitude magnetic dip respectively.