2025/06/28 by Liu, Peng, Wang, Mingyang, Yuan, Jianping +4
#FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #Solar and Stellar Astrophysics (astro-ph.SR)
paper · doi:10.48550/arxiv.2506.22765
We conducted a timing analysis of PSR J0922+0638 (B0919+06) using data from the Nanshan 26 m radio telescope and the MeerKAT telescope, spanning from January 2001 to March 2023. During this 22-year period, we discovered a previously unreported small glitch (glitch 1) before the well-known large glitch (glitch 2), occurring at \rm MJD ∼ 53325(3), with a frequency jump amplitude of Δν/ν∼ 0.79(6) × 10-9. We also identified ten slow glitch events, half of which were newly detected. These slow glitches occurred quasi-periodically, with an average interval of approximately 553(21) days, fractional frequency changes ranging from Δν/ν∼ 1.13(1) × 10-9 to 4.08(5) × 10-9, and a maximum fractional change in the first derivative of the frequency of Δν/ν ∼ -4.6 × 10-3. Additionally, our timing noise analysis reveals a change in the spectral index for noise power before and after glitch 2, with values of -6.0 and -5.3, respectively, likely due to this large glitch. Throughout the entire observation period, the first derivative of the spin frequency (ν) showed a periodic structure. The possible modulation period was estimated to be 537(24) days before the 700-day data gap at MJD 56716 and 600(58) days afterward. We discuss the periodic oscillations in pulsar rotation as a possible manifestation of spin-down noise and quasi-periodic slow glitches.