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تسجيل مستخدم جديدThe Crustal Rigidity of a Neutron Star, and Implications for PSR 1828-11 and other Precession Candidates
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We calculate the crustal rigidity parameter, b, of a neutron star (NS), and show that b is a factor 40 smaller than the standard estimate due to Baym & Pines (1971). For a NS with a relaxed crust, the NSs free-precession frequency is directly proportional to b. We apply our result for b to PSR 1828-11, a 2.5 Hz pulsar that appears to be precessing with period 511 d. Assuming this 511-d period is set by crustal rigidity, we show that this NSs crust is not relaxed, and that its reference spin (roughly, the spin for which the crust is most relaxed) is 40 Hz, and that the average spindown strain in the crust is 5 times 10^{-5}. We also briefly describe the implications of our b calculation for other well-known precession candidates.
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