2007/04/07 by Fangjun Lu, Q. Daniel Wang, E. V. Gotthelf +1
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Pulsars and Gravitational Waves Research #astro-ph
paper · pdf · doi:10.1086/518713
published as Astrophys.J.663:315-319,2007 · 14 pages with 7 figures included, accepted to ApJ
arxiv created 2007/04/07 · openalex publication_date 2007/06/22 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
We present new X-ray timing and spectral observations of PSR J1930+1852, the young energetic pulsar at the center of the nonthermal supernova remnant G54.1+0.3. Using data obtained with the Rossi X-Ray Timing Explorer ( RXTE ) and Chandra X-ray observatories we have derived an updated timing ephemeris of the 136 ms pulsar spanning 6 years. During this interval, however, the period evolution shows significant variability from the best-fit constant spin-down rate of = 7.5112(6) × 10 -13 s s -1 , suggesting strong timing noise and/or glitch activity. The X-ray emission is highly pulsed (71% ± 5% modulation) and is characterized by an asymmetric, broad profile (~70% duty cycle) that is nearly twice the radio width. The spectrum of the pulsed emission is well fitted with an absorbed power law of photon index Γ = 1.2 ± 0.2; this is marginally harder than that of the unpulsed component. The total 2-10 keV flux of the pulsar is 1.7 × 10 -12 ergs cm -2 s -1 . These results confirm PSR J1930+1852 as a typical Crab-like pulsar.