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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 - PowerPoint PPT Presentation
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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
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Glitches in the Crab pulsar
● Small glitch/3yr● Decay rapidly● Permanent increase in slowdown rate after the glitch
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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
Glitch Parameters:
Q=0.8(4)
810)8(4.2/
310)2(5/
d4
410)9(28.1/ p
Short fits of the Crab glitch
Glitches in the Crab pulsar
Glitches in the Vela Pulsar
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1996 , Oct , UT13.394MJD ~ 50369.394Q~0.4
62.15(2) 10 900 dd
Linear increase of vdot
Other glitches
• Frequent glitching pulsars• Various glitch recovery• Slow glitch• Tiny glitches• Unseen glitches
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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
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频繁跃变的脉冲星— PSR B1737-30 的 8 个跃变
W. Z. Zou,N. Wang, R. N. Manchester,et al 2008, MNRAS, 384, 1063J. P. Yuan, N. Wang, R. N. Manchester, Z. Y. Liu, 2009, MNRAS
• 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
9 610 2 10
61.85 10
Various glitch recovery多种形式的周期跃变恢复过程
J. P. Yuan, N. Wang, R. N. Manchester, Z. Y. Liu ,拟投稿 MNRAS
• Vela like 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
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
Tiny glitches 微跃变 11 910 10
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
Glitch Model:
◇ Amplitude in ΔP and agree with our observation◇ In agreement with the Crab pulsar glitch:
◇ Correlation in sign
ttQtt pdg )]/exp(1(1[)()( 0
pdd tt )/exp()(
Fractional decayQ = △νd/ △νg
Size △ν/ν=10-6
time constant τd=400 d
P
0P 0pP
•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.
• Detected one glitch in PSR J1835-1106
Other pulsars
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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.
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Statistics
The glitch activity is
proportional to spin-
down rate
1 gg
g
At
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Statistics
• 199 glitches in 63 pulsars,• Mostly occur in young pulsars.
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
直径2
0
公
里
外核,原子粒子流
内核,固态亚原子粒子?
极端物理条件下的固态物理
2I R
I R
当 Δν/ν=10-8 : ΔR=-0.1mm
星 震 由于偶极辐射损由于偶极辐射损
失能量,脉冲星的自转失能量,脉冲星的自转
并不是常数,它们是逐并不是常数,它们是逐
渐减慢的。能量被注入渐减慢的。能量被注入
到超新星遗迹。然到超新星遗迹。然
而而…………
28
跃变的产生:基于中子星的解释 Starquake model: change in ellipticity
Two component models-crust and superfluid: sudden unpinning of superfluid vortices, release the angular momentum to the crust
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跃变的产生:基于中子星的解释
Try to solve different type of pulsar glitches:•Crab like•Vela like•Old pulsars•Slow glitch pulsars
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Timing Noise
Continuous Restless Small scale
Red Long term Quasi-periodic
Activity parameter
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3( ) log6
t t
If t=108, we have Δ8.Fit to many pulsars we have:
8 6.6 0.6 log( )P
• Phase noise ∝ t1/2
• Frequency noise ∝ t3/2
• Frequency-derivative (slowdown) noise ∝ t5/2
Random walk in , and
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