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Precision Timing Measurements of PSR J1012+5307

Ch. Lange·F. Camilo·N. Wex·M. Kramer·D. C. Backer·A. G. Lyne·O. Doroshenko
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Abstract

We present results and applications of high precision timing measurements of the millisecond pulsar J1012+5307. Combining our radio observations with results based on optical observations, we derive complete 3-D velocity information for this system. Correcting for Doppler effects, we derive the intrinsic spin parameters of this pulsar and a characteristic age of 8.6 +/- 1.9 Gyr. Our upper limit for the orbital eccentricity of only 8 * 10^-7 (68% C.L.) is the smallest ever measured for a binary system. We demonstrate that this makes the pulsar an ideal laboratory to test certain aspects of alternative theories of gravitation. Our precise measurements suggest deviations from a simple pulsar spin-down timing model, which are consistent with timing noise and the extrapolation of the known behaviour of slowly rotating pulsars.

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Ch. Lange, F. Camilo, N. Wex, M. Kramer, D. C. Backer, A. G. Lyne, O. Doroshenko. 2001-02-18. Precision Timing Measurements of PSR J1012+5307. https://doi.org/10.1046/j.1365-8711.2001.04606.x

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