Accurate Position of a Second Pulsed Radio Source
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°.
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