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脉冲星时间噪声和周期跃变

脉冲星时间噪声和周期跃变. Timing irregularities. Timing noise: random fluctuation in pulse frequency with δ ν / ν ＜ 10 -9 Glitch: pulse frequency suddenly increases with 10 -9 ＜ Δ ν / ν ＜ 10 -6. (Lyne et al. 2000). Glitches in the Crab pulsar. ● Small glitch/3yr ● Decay rapidly

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脉冲星时间噪声和周期跃变

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  1. 脉冲星时间噪声和周期跃变 Pulsar Workshop - 2009, NAOC

  2. Timing irregularities • Timing noise: random fluctuation in pulse frequency with δν/ν＜ 10-9 • Glitch: pulse frequency suddenly increases with 10-9＜ Δν/ν＜10-6 Pulsar Workshop - 2009, NAOC

  3. (Lyne et al. 2000)

  4. Glitches in the Crab pulsar ● Small glitch/3yr ● Decay rapidly ● Permanent increase in slowdown rate after the glitch PSR B0531+21 Epoch 51562.7279 ν0=29.845547780(3) s-1 ν1=-3.7457341(7)x10-10 s-2 ν2= 1.0161006(4)x10-20 s-3 ν3=-6.0x10-31 s-4 DM= 56.77(2) cm-3 pc Pulsar Workshop - 2009, NAOC

  5. Glitches in the Crab pulsar Short fits of the Crab glitch Glitch Parameters: Q=0.8(4)

  6. two glitches in PSR B0531+21 (Crab pulsar)

  7. Glitches in the Vela Pulsar 1996，Oct，UT13.394 MJD ~ 50369.394 Q~0.4 Linear increase of vdot Pulsar Workshop - 2009, NAOC

  8. Change of of the Vela Pulsar Pulsar Workshop - 2009, NAOC

  9. Other glitches • Frequent glitching pulsars • Various glitch recovery • Slow glitch • Tiny glitches • Unseen glitches Pulsar Workshop - 2009, NAOC

  10. 频繁跃变的脉冲星Frequent glitching pulsars • PSR B0531+21（The Crab pulsar） • PSR B0833－45（The Vela pulsar） • PSR J0537－6910 • PSR B1338－62 • PSR B1737－30 • PSR B1800－21 • PSR B1046－58 Pulsar Workshop - 2009, NAOC

  11. 频繁跃变的脉冲星— PSR B1737-30的8个跃变 • 20年一共探测到22个周期跃变，相对变化幅度范围在 • 增加 • 最大跃变为： • PSRs J0537−6910, B0833−45, B1046−58 and B1800−21的跃变幅度变化较大，及B1737－30 • PSRs B1338−62, B1757−24 and B1758−23 跃变幅度较均一 W. Z. Zou,N. Wang, R. N. Manchester,et al 2008, MNRAS, 384, 1063 J. P. Yuan, N. Wang, R. N. Manchester, Z. Y. Liu, 2009, MNRAS

  12. Various glitch recovery多种形式的周期跃变恢复过程 • Velalike permanent change in frequency derivative: PSRs • B1046－58, B1610－50, B1706－44 (103—104yr) • Others no permanent change: PSRs B1338－62, J1617－5055, B1737－30, J1708－4009, B1757－24， J2021+3651 J. P. Yuan, N. Wang, R. N. Manchester, Z. Y. Liu，拟投稿 MNRAS

  13. Slow glitch 慢跃变 Zou, W. Z.; Wang, N.; Wang, H. X. et al. 2004, MNRAS, 354, 811 J. P. Yuan, N. Wang, R. N. Manchester, Z. Y. Liu, 2009, MNRAS

  14. Tiny glitches微跃变 PSRs B0144+59, B0402+61, B0525+21, J1705−3423, B1815−14, B1900+06, B1907+10和B2224+65 J. P. Yuan, N. Wang, R. N. Manchester, Z. Y. Liu，已投稿 MNRAS

  15. Unseen glitches

  16. Glitch Model: Fractional decayQ = △νd/△νg Size △ν/ν=10-6 time constant τd=400 d ◇ Amplitude in ΔP and agree with our observation ◇ In agreement with the Crab pulsar glitch: ◇ Correlation in sign

  17. Other pulsars • Detected one glitch in PSR J1835-1106 • Significant cubic terms with opposite signs are present in the pre- and post-glitch data, suggesting a sign change in at the time of the glitch.

  18. The jump in at MJD 52220 has the reversed sign of before and after the glitch. There was little or no change in at the time of the glitch. Pulsar Workshop - 2009, NAOC

  19. Statistics Pulsar Workshop - 2009, NAOC

  20. Statistics Pulsar Workshop - 2009, NAOC

  21. Statistics Pulsar Workshop - 2009, NAOC

  22. Statistics • The glitch activity is proportional to spin-down rate Pulsar Workshop - 2009, NAOC

  23. Statistics Pulsar Workshop - 2009, NAOC

  24. Statistics Pulsar Workshop - 2009, NAOC

  25. Statistics Pulsar Workshop - 2009, NAOC

  26. Statistics • 199 glitches in 63 pulsars, • Mostly occur in young pulsars. Pulsar Workshop - 2009, NAOC

  27. 跃变的产生：基于中子星的解释 中子星的大气，超热等离子体 直径20公里 外壳层，200米深，核子+电子 内壳层，晶体结构1km, 核子+电子+中子滴 外核， 原子粒子流 内核，固态亚原子粒子？

  28. 跃变的产生：基于中子星的解释 • Starquake model: change in ellipticity 由于偶极辐射损失能量，脉冲星的自转并不是常数，它们是逐渐减慢的。能量被注入到超新星遗迹。然而…… 星 震 当Δν/ν=10-8：ΔR=-0.1mm 极端物理条件下的固态物理

  29. 跃变的产生：基于中子星的解释 • Two component models-crust and superfluid: sudden unpinning of superfluid vortices, release the angular momentum to the crust • Try to solve different type of pulsar glitches: • Crab like • Vela like • Old pulsars • Slow glitch pulsars Pulsar Workshop - 2009, NAOC

  30. Timing Noise • Continuous • Restless • Small scale • Red • Long term • Quasi-periodic Pulsar Workshop - 2009, NAOC

  31. Timing Noise——data from Urumqi

  32. Activity parameter If t=108, we have Δ8. Fit to many pulsars we have: • Phase noise ∝t1/2 • Frequency noise ∝t3/2 • Frequency-derivative (slowdown) noise ∝t5/2 Pulsar Workshop - 2009, NAOC

  33. 残差与周期和周期导数 Pulsar Workshop - 2009, NAOC

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