Age of a millisecond binary pulsar

摘要

The recently reported properties of the millisecond binary pulsar J1012+5307 and its-white-dwarf companion suggest that the ages of such systems can be substantially overestimated. Lorimer et al. determined a characteristic age of the radio pulsar to be 7,000 million years (7 Gyr), whereas they estimated the companion to be at the most 0.3 Gyr old. The latter age was based on cooling timescales for white dwarfs, as calculated by Iben and Tutukov, and led to the suggestion that the pulsar did not start on the spin-up line, but near its current spin period of 5 milliseconds.