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تسجيل مستخدم جديدProper motion, age and initial spin period of PSR J0538+2817 in S147
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We present results of timing observations of the 143-ms pulsar J0538+2817 that provide a proper motion measurement which clearly associates the pulsar with the supernova remnant S147. We measure a proper motion of 67$_{-22}^{+48}$ mas yr$^{-1}$, implying a transverse velocity of $v= 385^{+260}_{-130}$ km s$^{-1}$. We derive an age of the pulsar and S147 of only $30pm4$ kyr which is a factor of 20 times less than the pulsars characteristic age of $tau_c = 620$ kyr. This age implies an initial spin period of $P_0=139$ ms, close to the present pulse period and a factor of several larger than what is usually inferred for birth periods. Implications for recent X-ray detections of this pulsar are discussed.
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