Accurate Position of a Second Pulsed Radio Source

Abstract

In a preceding communication, Pilkington et al. ¹ have reported the discovery of three more pulsed radio sources of the type recently described by Hewish et al. ². One of these sources, CP.0950, is particularly interesting because its period, 0·25307 s, is considerably shorter than those of the other three. This source also shows a much more rapid frequency sweep in the pulse suggesting that the dispersion introduced by the intervening medium is smaller; using a reasonable value (N _e = 0·1 cm^-3) for the interstellar electron density it seems probable that the distance of CP.0950 does not exceed 30 pc. The source lies at a high galactic latitude (b ^II = 44°) so there is therefore a much better possibility of identifying it with an intrinsically faint star than for the case of CP.1919 which lies at b ^II = 4°.