NOPR Collection:

Nighttime Fading of an If Radio Signal due to Irregularlties in Lower Ionosphere

Sat, 01 Dec 1973 00:00:00 GMT

Title: Nighttime Fading of an If Radio Signal due to Irregularlties in Lower Ionosphere Authors: Sinha, A.K.; Saha, B. Abstract: Two distinctive periods of finding were observed in the night time recording of field strength of an If radio-navigational signal on 280 kHz transmitted from China Bay (lat.9ᵒ11’ N; long. 81ᵒ11’E) in Ceylon, at a distance of about 1800 Km from Calcutta (lat. 22ᵒ34’N, long. 88ᵒ24’E). The result obtain suggest an origin of the two distinctive fading periods from two different scale size, ranges of the drifting irregularities at the Ionospheric region involved. Further, it is observed that the longer period would be dominant at an effective frequency of 50 kHz. Page(s): 297-288

Propagation of an hf Signal over a Long Transequatorial Path in the Afro-Asian Zone

Sat, 01 Dec 1973 00:00:00 GMT

Title: Propagation of an hf Signal over a Long Transequatorial Path in the Afro-Asian Zone Authors: Sen, A. K.; Trehan, S. K. Abstract: Field strength of hf signal in the 11m band propagated through a transequatorial path from the South African Station at Johannesburg (26° 13' S; 28° 56' E) has been recorded in Calcutta (22° 34' N; 88° 24' E). The records exhibit a tendency for the signal strength to attain a maximum around 1745 hrs IST. The results obtained have been discussed in relation to the behaviour of the equatorial anomaly at the ionospheric reflection points involved. Page(s): 296-297

Thermal Conduction in Protonosphere - An Exact Solution of Heat Flow Equation

Sat, 01 Dec 1973 00:00:00 GMT

Title: Thermal Conduction in Protonosphere - An Exact Solution of Heat Flow Equation Authors: Singh, B.; Sharma, S Abstract: An exact solution to the heat equation for the protonospheric plasma is obtained. The variations of temperature in the nighttime protonospheric plasma are analyzed in the fight of this solution. Page(s): 293-295

Massive Spheres in General Relativity & Large Gravitational of Quasars

Sat, 01 Dec 1973 00:00:00 GMT

Title: Massive Spheres in General Relativity & Large Gravitational of Quasars Authors: Durgapal, M. C.; Gehlot, G. L. Abstract: The effect of a layer of high density matter surrounding a spherical configuration has been studied. It has been shown that the maximum surface red-shift z_s can be as large as 4^.828. It is also shown that z_s, and (radius) ratio increase when a sphere is surrounded by a layer of high density matter. Models of quasar proposed and the ratios (core mass/total mass) for some quasars with z_s> 2 have been tabulated for two specific distributions of matter at the core. Page(s): 287-292