1. 磁場散逸を考慮したパルサー星雲の閉じ込めについて
Shuta J. Tanaka (Konan Univ.)
with
K. Toma (Tohoku Univ.) & N. Tominaga (Konan Univ.)
25, Nov., 2017, ~中性子星の観測と理論~ 研究活性化ワークショップ 国立天文台

2. Introduction

3. Pulsars & PWNe Pulsar Wind Nebulae (PWNe) are powered by pulsars
Crab (Chandra)
Pulsar Wind Nebulae (PWNe) are powered by pulsars
Pulsed emission ~ a few % of Lspin.
Most of Lspin release as relativistic magnetized flow, called pulsar winds.
~ 70 of 2500 pulsars have observable PWNe.

4. Crab Nebula & Pulsar spectra in radio (Bietenholz+15)
PWNe observations
Broadband emission from radio to TeV
Brighter than pulsar itself.
Large angular extent (~ pc in size)
Confined by supernova remnant (SNR)
Expansion and flux evolution
Crab Nebula & Pulsar spectra
(Buhler&Blandford14)
SNR G
diff. image ( )
in radio (Bietenholz+15)
PWN G
Filament motion in opt.
(Nugent+98)
PSR J
G (Chandra)

5. σ-problem

6. Structure of PWNe Light cylinder RLC~108cm Termination Shock
SNR G
PWN G
Crab (Chandra)
Crab (Composite)
Crab (HST)
PSR J
G (Chandra)
Light cylinder
RLC~108cm
Termination Shock
RTS~ 0.1pc
Contact
Discontinuity
RPWN ~ 2pc
Shock Ⅰ Ⅱ Ⅲ Ⅳ Ⅴ
pulsar
Magneto-
sphere
Pulsar wind
region
Pulsar wind nebula
(shocked pulsar wind)
Shocked SN ejecta
Unshocked SN ejecta
+ ISM
vexp << c
(vth ~ c)
vexp ~ c

7. Expansion of PWN is much slower (~ 103 km/s) than pulsar wind (~ c)
KC model
Kennel & Coroniti (1984a, b) (c.f., Rees & Gunn 1974)
1D static MHD model of PWN
Expansion of PWN is much slower (~ 103 km/s) than pulsar wind (~ c)
magnetization of pulsar wind: σ = particle energy flux / Poynting flux
Image of PSR
taken from NASA
Flow velocity [~ v / c]
Distance [r / RTS]
Kennel&Coroniti1984a
v∞ ~ vexp ~ σ c ~ 103 km/s
σ-problem

8. in radio (Bietenholz+15)
Beyond KC model
KC model = 1D static MHD model
1D?
MHD?
static?
Crab (Chandra)
Porth+14a
diff. image ( )
in radio (Bietenholz+15)
Lyutikov+10
3D effects (turbulence)
&
B-field dissipation
(non-ideal MHD)
are discussed.

9. Turbulent B-field
Crab (Chandra)
Shibata+03
Shibata+03
Bucciantini17

10. Magnetic Dissipation

11. Minimum torque by Michel’69
Early Simple Models
Fireball
(Acceleration)
KC model of PWN
(Deceleration)
Low-σ
High-σ
Minimum torque by Michel’69
(Acceleration)

12. B-field conversion & dissipation
Our Model
τdiss : B-field dissipation
τconv: B-field conversion
Λrad: Radiative cooling
TTT17 in prep.
TTT17 in prep.
TTT17 in prep.
c.f., Drenkhan02
TTT17 in prep.
TTT17 in prep.
TTT17 in prep.
B-field conversion & dissipation

13. Results: 4-velocity σ

14. KC modelとの比較
Ishizaki+17
Ishizaki+17
TTT17 in prep.

15. Deceleration of relativistic magnetized outflow is studied.
Summary
Deceleration of relativistic magnetized outflow is studied.
Heuristic model of B-field dissipation is adapted.
B-field dissipation leads efficient deceleration of outflow.
Multi-dimensional effects are not required for deceleration.
Further studies
Broadband emission map
c.f., Drenkhan02