202139 Pulsar Workshop 2009 Beijng 4 202139 Pulsar

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色 散 2021/3/9 Pulsar Workshop, 2009, Beijng 4

色 散 2021/3/9 Pulsar Workshop, 2009, Beijng 4

散射 导致脉冲轮廓展宽 2021/3/9 Pulsar Workshop, 2009, Beijng 5

散射 导致脉冲轮廓展宽 2021/3/9 Pulsar Workshop, 2009, Beijng 5

散射 导致脉冲轮廓展宽 2021/3/9 Pulsar Workshop, 2009, Beijng 6

散射 导致脉冲轮廓展宽 2021/3/9 Pulsar Workshop, 2009, Beijng 6

Apparent source diameters S 2021/3/9 d D-d Pulsar Workshop, 2009, Beijng 10

Apparent source diameters S 2021/3/9 d D-d Pulsar Workshop, 2009, Beijng 10

星际介质在空间的分布 β=11/3:Kolmogorov谱 当β≥ 4 时,陡谱模型 ( Bandford & Narayan 1985 ) 内尺度模型(inner scale)(Coles et

星际介质在空间的分布 β=11/3:Kolmogorov谱 当β≥ 4 时,陡谱模型 ( Bandford & Narayan 1985 ) 内尺度模型(inner scale)(Coles et al. 1987) 2021/3/9 Pulsar Workshop, 2009, Beijng 12

描述DISS动态谱(薄屏模型) Theory prediction of DISS parameters (Thin scattering screen model) β<4 β>4 Kolmogorov谱 (β=11/3):

描述DISS动态谱(薄屏模型) Theory prediction of DISS parameters (Thin scattering screen model) β<4 β>4 Kolmogorov谱 (β=11/3): 2021/3/9 Pulsar Workshop, 2009, Beijng 16

V iss: Pulsar transverse velocities derived from diffractive scintillation spectra: 脉冲星的自行为主导 地球公转速度沿视线 方向曲线变化 忽略介质速度

V iss: Pulsar transverse velocities derived from diffractive scintillation spectra: 脉冲星的自行为主导 地球公转速度沿视线 方向曲线变化 忽略介质速度 曲线变化

Gupta (1994): Thin screen, S d D-d 18

Gupta (1994): Thin screen, S d D-d 18

 =11/3: Kolmogorov fluctuation spectrum =4 2021/3/9 Pulsar Workshop, 2009, Beijng 19

=11/3: Kolmogorov fluctuation spectrum =4 2021/3/9 Pulsar Workshop, 2009, Beijng 19

u=s. F/sd : describe the scattering strength s. F is the Fresnel scale at

u=s. F/sd : describe the scattering strength s. F is the Fresnel scale at the scattering disk at which the geometric phase difference is 1 radian compared to the direct path; sd is a scale at the observer at which the average phase changes is 1 radian. u<1: weak scattering u>1: strong scattering

2021/3/9 Pulsar Workshop, 2009, Beijng 21

2021/3/9 Pulsar Workshop, 2009, Beijng 21

流量变化和调制指数 2021/3/9 Pulsar Workshop, 2009, Beijng 22

流量变化和调制指数 2021/3/9 Pulsar Workshop, 2009, Beijng 22

For nearby pulsars, the modulation is weak, and DISS will be main effect. For

For nearby pulsars, the modulation is weak, and DISS will be main effect. For Kolmogorov spectrum, m u 5/6 → m<1 For larger DM, DISS effect is weaker, and m DM-1. But RISS is stronger, with m u-1/3. (u D, so m DM-1/3) 2021/3/9 Pulsar Workshop, 2009, Beijng 23

Oral presentation at IAUC 182 Submitted to CJAA Diffractive scintillation(DISS): Refractive scintillation(RISS): d :

Oral presentation at IAUC 182 Submitted to CJAA Diffractive scintillation(DISS): Refractive scintillation(RISS): d : short long △ d: narrow wide

闪烁研究 五颗脉冲星在 1540 MHz的长期星际闪烁监测 l 每 9天观测一次,数据 2001年 1月2002年 6月 l 积分2-6 hr,子积分2-4 min

闪烁研究 五颗脉冲星在 1540 MHz的长期星际闪烁监测 l 每 9天观测一次,数据 2001年 1月2002年 6月 l 积分2-6 hr,子积分2-4 min l 被观测脉冲星: PSR B 0329+54 PSR B 1823+26 PSR B 1929+10 PSR B 2020+28 PSR B 2021+51 Pulsar Workshop, 2009, Beijng 25 2021/3/9 Wang, N. ; Manchester, R. N. ; Johnston, S. ; Rickett, Bet al. : 2005, MNRAS, 358, 270

PSR B 0329+54 的动态谱 DM= 26. 8 pc cm-3 D = 1. 06 kpc

PSR B 0329+54 的动态谱 DM= 26. 8 pc cm-3 D = 1. 06 kpc 3 hr 的观测 结果: Δtd~ 10 -30 min Δνd ~ 5 -15 MHz 2021/3/9 Pulsar Workshop, 2009, Beijng 26

闪烁二维动态谱 2021/3/9 Pulsar Workshop, 2009, Beijng 28

闪烁二维动态谱 2021/3/9 Pulsar Workshop, 2009, Beijng 28

二维自相关函数 2021/3/9 Pulsar Workshop, 2009, Beijng 29

二维自相关函数 2021/3/9 Pulsar Workshop, 2009, Beijng 29

2021/3/9 Pulsar Workshop, 2009, Beijng 30

2021/3/9 Pulsar Workshop, 2009, Beijng 30

Modelling ACFs for PSR B 0329+54 strong scattering thin disk Kolmogorov spectrum

Modelling ACFs for PSR B 0329+54 strong scattering thin disk Kolmogorov spectrum

闪烁参数与频率的依赖关系 a. b. c. d. 2021/3/9 Bhat, Rao & Gupta 1999 Gupta, Rickett &

闪烁参数与频率的依赖关系 a. b. c. d. 2021/3/9 Bhat, Rao & Gupta 1999 Gupta, Rickett & Lyne 1994 Stinebring, Fainon & Mckinnon 1996 Our results Pulsar Workshop, 2009, Beijng 32

Daily Observations of Interstellar Scintillation in PSR B 0329+54 Obs: Mar 12— 31, 2004

Daily Observations of Interstellar Scintillation in PSR B 0329+54 Obs: Mar 12— 31, 2004 Wang, N. ; Yan, Z. ; Manchetser, R. N. et al. : 2008, MNRAS

Daily Observations of Interstellar Scintillation in PSR B 0329+54

Daily Observations of Interstellar Scintillation in PSR B 0329+54

Modulation indices Observed > prediction !!

Modulation indices Observed > prediction !!

闪烁参数的互相关 Cross correlation Wang, N. ; Yan, Z. ; Manchetser, R. N. et al.

闪烁参数的互相关 Cross correlation Wang, N. ; Yan, Z. ; Manchetser, R. N. et al. : 2008, MNRAS, accepted

二次谱 Secondary Spectra, Two dimensional FFT of dynamic spectrum Observing the structure of central

二次谱 Secondary Spectra, Two dimensional FFT of dynamic spectrum Observing the structure of central image !

2021/3/9 Pulsar Workshop, 2009, Beijng 40

2021/3/9 Pulsar Workshop, 2009, Beijng 40

Kolmogorov Spectrum β=3. 67

Kolmogorov Spectrum β=3. 67

折射式衍射特征时间 Theory prediction:

折射式衍射特征时间 Theory prediction:

Structure Function

Structure Function

TC 93模型 Taylor & Cordes 1993 2021/3/9 NE 2001模型 Cordes & Lazio 2003 a,

TC 93模型 Taylor & Cordes 1993 2021/3/9 NE 2001模型 Cordes & Lazio 2003 a, b Pulsar Workshop, 2009, Beijng 45

闪烁和自行速度的相关性 Harrison & Lyne 1993 2021/3/9 Gupta 1995 Pulsar Workshop, 2009, Beijng 46

闪烁和自行速度的相关性 Harrison & Lyne 1993 2021/3/9 Gupta 1995 Pulsar Workshop, 2009, Beijng 46

 2021/3/9 Putney & Stinebring 2006 Pulsar Workshop, 2009, Beijng 47

2021/3/9 Putney & Stinebring 2006 Pulsar Workshop, 2009, Beijng 47

2021/3/9 Pulsar Workshop, 2009, Beijng 48

2021/3/9 Pulsar Workshop, 2009, Beijng 48

 Putney & Stinebring 2006

Putney & Stinebring 2006