活動銀河核ジェットにおけるシンクロトロン放射電子の空間分布
荻原大樹
筑波大学 計算科学研究センター PD1年目

2021/06/25 14:30-15:00, 2021年度第1回 宇宙史研究センター構成員会議, online΋ͷΛ΋͋Δ (1pc ≈ 3.085 × 10cm)ɻ δΣοτͷதʹ͸ɺϒϩοϒ΍ϊοτͱ‫ݺ‬͹Ε

Active Galactic Nuclei jets
and their host galaxies• collimated relativistic outflow fromAGN

• extends over ~kpc - ~Mpc
• emission from radio to gamma-ray• Almost jets belong to elliptical galaxies• ~10% of AGN have a jet(radio-quiet : radio-loud = 9 : 1)

• possible heating source of galaxy
clusters (cooling flow problem)

Cyg A (NRAO/AUI)ਤ 1.1: Very Large Array (VLA) ి೾๬ԕ‫ʹڸ‬Αͬͯ 1983 ೥ʹ 6cm(5GHz) Ͱ‫؍‬ଌ͞Εͨ
Cyg A ۜՏ (த৺ͷ໌Δ͍఺)ɻ฼ۜՏͷத৺͔֩Β৳ͼΔඇৗʹࡉ͍ 2 ͭͷδΣοτ͕ଘࡏ͢Δ͜ͱ͕Θ͔ΔɻδΣοτઌ୺ʹ͸‫ڊ‬େͳ๐ঢ়ߏ଄ (ϩʔϒ) ͕͋ΔɻδΣοτ͕ઌ୺Ͱࢄҳͯ͠Ͱ͖Δϩʔϒ͕໌Δ͍͜ͱ͔Β FR 2 ‫ిܕ‬೾ۜՏʹ෼ྨ͞Ε͍ͯΔɻ(Copy
Right: NRAO/AUI)Δմঢ়ͷ໌Δ͍ྖҬΛ΋ͭ΋ͷ͕͋Δɻಉ͡δΣοτΛִ࣌ؒؒΛͱͬͯ‫؍‬ଌ͢Δ͜ͱʹΑΓϊοτ͕ޫΑΓ΋଎͘Ҡಈ͍ͯ͠Δ༷ࢠ͕֬ೝ͞Ε͍ͯΔɻ͜͏ͨ͠ӡಈ͸௒ޫ଎ӡಈͱ‫ݺ‬͹ΕΔ͕ɺ࣮ࡍ͸ɺ์ࣹ‫͕ݯ‬૬ର࿦తʹӡಈ͍ͯ͠Δ͜ͱʹΑΔ‫͚͔ݟ‬ͷޮՌͱͯ͠આ໌Ͱ͖Δɻ௒ޫ଎ӡಈ͸ɺδΣοτ಺ͷ෺࣭͕ɺޫ଎ʹඇৗʹ͍ۙ଎౓Ͱӡಈ͍ͯ͠Δ͜ͱΛ͍ࣔࠦͯ͠Δɻͨͩ͠ɺϊοτͷதʹ͸ҐஔΛม͑ͳ͍΋ͷ΍ AGN ํ޲΁ͱӡಈ͍ͯ͠Δ΋ͷ΋͋Δɻϊοτͷӡಈ͸ɺྲྀମͷӡಈͱؔ܎ͷͳ͍์ࣹྖҬͷ࣌ؒมԽΛ‫͍ͯݟ‬ΔՄೳੑ΋͋Δ͜ͱʹ஫ҙ͞Ε͍ͨɻ

M87 (NASA)

Cen A (NASA)“A curious straight ray lies in a gap in the nebulosity in p.a. 20°, apparently
connected with the nucleus by a thin line of matter. The ray is brightest at its inner
end, which is 11’’ from the nucleus.”

description of NGC 4486 (M87), Heber D. Curtis, 1918ୈ 1 ষ INTRODUCTION

8Radio observations

M87

more and more upstream(NRAO/NSF)

Continuing triple-ridge structure• High-resolution VLBI

observations have revealed
characteristic emission
structures of AGN jets.

triple-ridge structureਤ 1.2: 1989 ೥ʹ VLA Ͱࡱ૾͞Εͨ M87 ۜՏɻ਺ Mpc ·Ͱ৳ͼΔδΣοτ͕‫؍‬ଌ͞Ε
The Astrophysical Journal,
817:131 (17pp),
2016 February
1
Hada et al.
͍ͯΔɻM87͸࠷΋ৄࡉʹδΣοτߏ଄͕‫؍‬ଌ͞Ε͍ͯΔఱମͰ͋ΓɺδΣοτ‫ڀݚ‬ͷ
HadaObserva2017ϩθολετʔϯͱ‫ݺ‬͹ΕΔ͜ͱ΋͋Δɻ(Credit:National Radio Astronomy
tory/National Science Foundation)• limb-brightened: M87, Mrk 501,
Mrk 421, Cyg A, 3C84

• triple-ridge: only in high-limb-brightened structureδΣοτͷ‫ܗ‬ঢ়͸ଟछଟ༷Ͱ
ɺ௕͘·͙ͬ͢৳ͼΔ΋ͷ΋͋Ε͹୹͘‫͕ۂ‬Γ͘Ͷͬͨ
z = 15mas
z = 30mas
z = 5mas΋ͷ΋͋Γɺ‫؍‬ଌ೾௕ʹΑͬͯ΋มԽ͢ΔɻCyg A ͷδΣοτ͸฼ۜՏΛத৺ʹ 2 ͭͷδΣοτ͕‫ʹ޲ํٯʹ͍ޓ‬৳ͼ͍ͯΔͷʹରͯ͠ɺM87 ͷδΣοτ͸ยํʹ͔͠৳ͼ͍ͯͳ͍ɻ࣮ࡍʹ͸ɺM87 ʹ΋ 2 ͭͷδΣοτ͕ଘࡏ͢Δ͕‫͍ͯ͑ݟ‬Δํͱ͸‫ٯ‬ଆͷδΣοτ͸զʑ͔Βԕ͔͟Δ޲͖ʹߴ଎Ͱ఻೻͍ͯͯ͠ɺ૬ର࿦తͳυοϓϥʔޮՌ΍ϏʔϛϯάޮՌʹΑͬͯ‫؍‬ଌ͞Εͳ͘ͳ͍ͬͯΔͱߟ͑ΒΕΔɻͲͪΒʹ΋‫ڞ‬௨͍ͯ͠Δͷ͸δΣοτ͕฼ۜՏ͔Β·͙ͬ͢৳ͼͨઌʹ‫ڊ‬େͳ๐ঢ়ߏ଄ (ϩʔϒ) ͕ଘࡏ͢Δ͜ͱͰ͋Δɻϩʔϒ͸δΣοτ͕੕ؒ෺࣭ͱিಥ͠ɺࢄҳ͢Δ͜ͱʹΑͬͯ‫ܗ‬੒͞ΕΔͱߟ͑ΒΕ͍ͯΔɻ΄ͱΜͲ௚ઢঢ়ͷδΣοτΛۜՏத৺ʹ޲͔͔ͬͯ͞ͷ΅ΔͱɺۜՏத৺ͷ௒‫ڊ‬େϒ
Event Horizon Telescope
Hada et al. 2016ϥοΫϗʔϧ෇ۙʹߦ͖ண͘ɻϒϥοΫϗʔϧ͸Ұൠ૬ରੑཧ࿦͕༧‫͢ݴ‬Δ࠷΋‫͍ڧ‬ॏྗ৔ͷ͜ͱͰ͋Γɺೖͬͯ͠·͏ͱޫͰ͑͞΋ൈ͚ग़͢͜ͱ͕Ͱ͖ͳ͍ྖҬͰ͋Δɻ౰વɺϒϥοΫϗʔϧ͔Β͸͍͔ͳΔ෺࣭΋֎΁ग़ͯ͘Δ͜ͱ͸Ͱ͖ͳ͍ɻϒϥοΫϗʔϧ͔Β
Figure 3. VLBA+GBT 86 GHz
false-color total intensity image of the M87 jet. The image is produced by combining the visibility data over the two epochs on 2014

sensitivity observation of M87• jet width profile (next slide)

Blackhole Shadow

February 11 and 26. The restoring beam (0.25 mas ×0.08 mas at PA 0°) is shown in the bottom-right corner of the image. The peak intensity is 500 mJy beam−1 anddistance from BH (pc)
10-4

10-3

10-2

The Astrophysical Journal, 817:131 (17pp), 2016 February 1

106

10-1

Hada et al.

2
1
10
10
Continuing triple-ridge structure

103

104

105
triple-ridge構造

z = 5masz = 15mas

104

z = 30masz∝R1.6

jet width :R(rS)limb-brightened構造z∝R2

Figure 3. VLBA+GBT 86 GHz false-color total intensity image of the M87 jet. The image is produced by combining the visibility data over the two epochs on 2014
February 11 and 26. The restoring beam (0.25 mas ×0.08 mas at PA 0°) is shown in the bottom-right corner of the image. The peak intensity is 500 mJy beam−1 andthe off-source rms noise level is 0.28 mJy beam−1, where the resulting dynamic range is greater than 1500 to 1.

Dc3C273 ~ Dc43 GHz + DcRM ~ 18 . Regarding M87, its
EVPA uncertainty in 86 GHz images would be somewhat
larger 3
than this value, since the lower S/N of polarization
signals (S/N∼4.5; see Section 3.4) from this source gives
another non-negligible thermal error term. This can be
estimated as Dctherm (radian) ~ sp 2P where sp and P arerms noise level and polarized intensity in the polarizationmap(e.g., Roberts et al. 1994). With S/N=P sp ∼4.5, we
obtain Dctherm,M87 ~ 6 . Assuming that Dc3C273 andDctherm,M87 are statistically independent, we estimate a total
error budget for M87 to be DcM87∼±20°.

calibration procedure. The basic information of these data isalso tabulated in Table 1.

10

102

3. RESULTS
3.1. New 86 GHz Images
In Figure 3 we show a representative 86 GHz image of the
M87 jet obtained by our VLBA+GBT observations. For abetter visualization, the image is produced by combining thevisibility data over the two epochs, and restored with aconvolving beam of 0.25 mas ×0.08 mas at a position angle(PA) of 0°. A contour image with a natural weighting scheme isalso displayed in the top panel of Figure 4.
Thanks to the signiﬁcant improvement in sensitivity, adetailed jet structure was clearly imaged down to the weaker
emission regions. The resulting image rms noise of the
combined image was ∼0.28 mJy beam−1. In this period theextended jet was substantially bright down to ∼1 mas from thecore. The weak emission was detected (particularly in thesouthern limb) down to ∼3 mas from the core at a level of 3σ,
and another ∼1–2 mas at 2σ. The peak surface brightness of theimage was 500 mJy beam−1 at this resolution, corresponding to
an image dynamic range greater than 1500 to 1 (the detailed
value varies slightly as a function of the weighting scheme andconvolving beam). This is the highest image dynamic range
obtained so far at 86 GHz for this jet, and is quite comparable
to typical dynamic ranges in VLBA images at 43 GHz(e.g., Ly
et al. 2007). We describe a comparison of our 86 and 43 GHz
images in the next subsection.

2.3. Lower-frequency Data

As supplementary data sets, we additionally made VLBAonly observations of M87 at 24 and 43 GHz close in time withthe 86 GHz sessions. The observations were carried out on
2014 March 8, 26, and May 8, where both 24 and 43 GHz wereused quasi-simultaneously by alternating the receivers quickly.
On March 26 and May 8, all the VLBA stations were present,
while on March 8 the antennas at Mauna Kea and Fort Davis
were absent. We received only RR polarization signals with a
total bandwidth of 128 MHz (on March 8) or 256 MHz (onMarch 26 and May 8). Among these sessions, the data on
March 26 were the best in overall quality, while the data on
March 8 were relatively poor. The initial data calibration(a priori amplitude correction, fringe-ﬁtting, and bandpass) was
made in AIPS, and the subsequent image reconstruction was
performed in Difmap based on the usual CLEAN/self-

EHT

10

5

1

approaching the jet origin!

z∝R
1

10

102

103

104

distance from BH: z(rS)

105

106

107

Nakamura et al. 2018108

A Zoom to the Black Hole in M87 - Hubble Space Telescope on Youtube

Blackhole Shadow

Jet emission near the horizon
Event Horizon Telescope

線形コントア

一般相対論的輻射磁気流体モデル

EHT 2017の観測条件に基づく模擬観測EHT 2020の観測条件に基づく模擬観測(Chael et al. 2019)

対数コントアAkiyama, Asada, Hada
天文月報 2019 年 7 月号 ASTRO NEWSਤ次世代EHT観測でジェット成分の検出が期待
1. ࠓ‫ޙ‬ͷ M87*ͷ‫؍‬ଌ༧૝ɻຊ‫؍‬ଌ͕࣮ࢪ͞Εͨ

2017 ೥ʹ͸࣮ޮ‫౓ײ‬ෆ଍ͷͨΊʹ‫ݕ‬ग़͕೉͔ͬ͠

電波ジェットの起源に迫る観測。
BH近傍の放射イメージを理論的に予測できるか

GRMHD simulationsjet+ radiative transfer calculations

B⊙
E(General Relativistic MagnetoHydroDynamic)

Striped jets from small scale magnetic field

11• The plausible jet launching mechanism is
the Blandford-Znajek process.

• rotational energy of BH→ Poynting flux
→ kinetic energy

disk• GRMHD simulations supports the BZ
process.

Mahlmann, Levinson, Aloy 2020

AstrophysicalJournal Letters, 875:L5 (31pp), 2019 April 10
Figure 8. 3D impression of the accretion of oneThemagnetic
flux
tube onto a rapidly spinning BH (a⇤ = 0.9) in the C-L4-L2 model.
The (outgoing) Poynting flux emerging from the BH horizon is
Figure 7. The B r and B ✓ components in the equatorial planevisualized by ribbons coloured according to the strength of the(model C-H4-L2) show periodic in-spiraling of magnetic flux onto
associated radial energy flow (CGS units; see the colour scale).
the central BH during two subsequent episodes of efficient enThe radial magnetic flux (absolute value) is depicted by the denergy extraction. The shown data has a grid resolution of x, y, z 
sity plot, indicating 3D non-axisymmetric e↵ects in the plunging
0.25rg . The emerging spiral patterns show 3D e↵ects in the plungregion. During peak outflow, extended helical structures of ening region, which break the axial symmetry.
ergy flow build up above the polar regions. Their confinement
and strength decreases after peak efficiency. Click for animation(only Adobe Reader).

• Combined with radiative transfer

calculations, one can create synthetic
images.

Porth et al. 2019
The EHT Collaboration et al.

Figure 1. Views of the radiatively inefficient tur
coordinates (subscript KS). Left: logarithmic rest
integral convolution (luminance), showing ordered
the magnetization with colored contours indicatin(red), the disk is indicated by = 1 (green) andregion outside of the funnel. Right: schematic ofand the ergosphere is shown as black contour. Thii) Opening up of the accreted loop and gradual extension of field lines linking the polar regions to larger verticalheights (Figure 9b).
discussion
on thesimilarities of numerical and physical reiii) Complete opening of the accreted
loop andinitializasistive e↵ects),
agreement with recently pretion of the rearrangement of the jet launchingregion.inInqualitative
thissented simulations
Bromberg et al. (2019); Davelaar et al.
phase the peak energy extraction efficiency
is attained.byThis
A relevantdi↵erence between the 2D models of Parcomes along with the formation of(2019).
larger-scale
flux strucfrey
et al. (2015)
and ours originates from the geometrytures form above the polar regions,developmentof plasand surface
areaof the current sheets between consecutive
moids with strong toroidal field dominanceat theinterfaceloops of alternate polarity. When loops plunge into the BH,of di↵erent polarizations (Figure 9c).
theplunging
shape theircommonand axialiii) Rearrangement of the fields in theregionensu- interface is paraboloidal
Figure 1. Left panel: an EHT2017 image of M87 from Paper IV of this series (see their Figure 15). Middle panel: a simulated image based on a GRMHD model. Rightsymmetric,
withtoroidal
a surface S2D . In contrast, panel:in 3Dtheitmodel
is aimage convolved with a 20 Nas FWHM Gaussian beam. Although the most evident features of the model and data are similar, ﬁne features in theing the development of extended regionsof strong→ comparison with observations andsimulations = “black hole shadow”

EHT 2019 paper 5

Non-thermal emission←非熱的放射モデル

from non-thermal particles• most GRMHD simulations consider only
thermal electrons• Emission from the jet is synchrotron emission
2

Kimura and Tom

Davelaar et al. 2019

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!!!!
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!!!

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bulk acceleration

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BH

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particle acceleration

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jet

〜
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!

• uncertainty of the density distribution
inside the jet→ uncertainty of the synthetic images 〜〜〜＞😉

"

!
!
!

←本研究

!

"

→ large scale dynamics of jets

reconnection!>• What is the spatial distribution?

turbulence

vationgalaxi!
!
2015).
througnectionon-th0connecSironi$9:
turbul#Comis
gamm(see F
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Kimura & Toma 2020
were"!!!!!>

shock? turbulence? magnetic reconnection?
pair-creation?
→ local particle physics

7#(10-)386(4)'

shock

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• How to accelerate electrons relativistically?

!!!

of relativistic electrons.

熱的放射モデル→Difficulty of Jet Simulation

The Astrophysical Journal, 801:56 (11pp), 2015 March 1

Density-floor problem• Thermal plasma cannot dissipate into thehighly magnetized region.

• In GRMHD simulations, the separation

surface between the inflow and outflow
emerges at the balanced surface of thegravity and the Lorentz force.

• Density becomes very low in the jet.

Due to the numerical difficulty, density isreplaced by “floor values” in simulations.
−4 −3/2−6 −5/2

e.g., ρ0;min = 10 r
, umin = 10
(McKinney & Gammie 2004)r

Pu et al. 2015
Figure 1. Schematic illustration of a Poynting ﬂux–dominated (PFD) GRMHD

シミュレーションでジェットを解くのは難しそう。
放射構造を再現することに集中して、準解析的近似解モデルを用いる。

Our Motivation
predict jet images in EHT scale• Focus on the internal structures of jets
• Construct a semi-analytic model which do not suffer the density floor
problem• Determine the density distribution in a jet near the black hole
• In future, our jet model combined with radiative transfer calculations predicts/
reproduce observed jet images and constrain the injection mechanisms.

Basic Equations• basic equations
Maxwell equation:μνμμν∇ν F = J , ∇ν * F = 0
Energy-momentum equation:

∇ν T

μν

= 0,

1
1
μν
μ ν
μλ ν
μν λσ
T = ρu u +F Fλ − g F Fλσ
)
4π (
4
μ

continuity equation: (nu );μ = 0νideal MHD condition: u Fμν = 0• Boyer-Lindquist coordinate in Kerr
spacetime• steady, axisymmetric ∂0 = 0, ∂3 = 0• divide the basic equations into the parallel
component to the field line (Bernoulli eq.)
and the perpendicular component (GradShafranov eq.)

Field Line Configuration• flux function:νΨ(r, θ) = C[(r/rH) (1 − cos θ) + (1/4)ϵr sin θ]• ν = 1: parabolic field shapeforce-free solution−4• ϵ = 10 : MHD deviation• C: constant. Ψ(rH, π/2) = 1• consistent with results of GRMHD
simulations

Lee & Park 2004, Beskin & Nokhrina 2006,
Tchekhovskoy+2008, Pu+2015

• 磁場:

G
G
B
t
t
1
1
B =
=−
F23 = −
∂2Ψ
g11
−g
−g
G
G
B
t
t
2
2
B =
=−
F13 = −
∂1Ψ
g22
−g
−g
2
1
2
Bp = B B1 + B B2

• 電場:
E1 = F01 = ΩF F13 = ΩF∂1ΨEBH
2 = F02 = ΩF F23 = ΩF∂2Ψ
E3 = 0Integral Constants• 4 constant quantities along a field line

ΩF B3
1. Energy flux per the rest-mass energy : Ê = − u0 +4πμη
B32. Angular momentum flux per the rest-mass energy: L̂ = u3 +
4πμη
nu1
nu2
3. mass flux per magnetic field flux: η = −Gt = −Gt
B1
B2
F01 F02
4. “angular velocity” of the field line: ΩF ==F13 F23

Striped jets from small scale magnetic field

11

Gt = g00 + ΩF g03

If the fluid don’t move along the filed line, it rotates with ΩF.

Mahlmann,Levinson, Aloy 2020

Wind Equation• analytic solution of the Bernoulli equation
4i
Aiup = 0,
∑
i=0

•
•

New formulation

number density: n = −

A3 =

k0Bp

2πμηGtk0Bp

A2 = 1 + E k4 +upGt
GϕÊ + Gt L̂
2
M − k0Gt = g00 + ΩF g03

Gϕ = g03 + ΩF g33

A1 =

2

( 4πμηGt )2̂
Bp(k0 − E k2)2̂ηBptoroidal field: B3 = − 4πμη

A4 = 12πμηGt2̂

( 4πμηGt )A0 = k0(k0 − E k2)

k0 = − (g00 + 2ΩF g03 + ΩF g33)

k2 = (1 − ΩF L/E)2

Bp

2

2
ρw2 = g03
− g00g33

k4 = − (g33 + 2g03L/E + g00(L/E)2)/ρw2

4 constants, 4 conditions
conditionsuseparation s• constrain four integral constants by fourrface

1. regularity condition of the magnetosonicpoint of outflow

separation surfaceで湧き出しあり
電磁場は連続的| up(r = rss) | = 10−3

3. electromagnetic condition at the horizon(Znajek condition)

New constraining method→ L, η

trans-field forcebalance → ΩF

4. trans-field force balance at the separation
surface (next slide)
我々はseparation surfaceでのみ質量流速を与える

fast magnetosonic point→E
流体はinflow/outflowで不連続、

2. initial poloidal velocity at the separation
surface

GRMHD simulationは質量流速を全面で手で与える

field lines

ΩF(Ψ = 1) = 0.35ΩH

BH

g33 1/2
g03
B3(r = rH ) = −− ΩF (∂2Ψ)−( g22 ) ( g33)→ L, η
r=rH

Results

Parabolic Jet Modelup

6• poloidal velocity:212
up = u1u + u2u• flow accelerate from theseparation surface

accelerate
up to• density normalization:

B1B 1 + B2B 2 + B3B 3
nnorm =
8πμ[]up ∼ 3 − 4
r=rss,Ψ=1←separation
surfaceOgihara, Ogawa & Toman/nnorm

Figure 1 shows ⌦F ( ) and L̂outaration surface. ⌦F /⌦H = 0.5 antion L̂out ⌦F /Êout = 1 are satisfi
in> 0.1, which mean thattions are consistent with the fortion (Blandford & Znajek 1977)
the monopole force-free solution
BH spin is smaller, Ê0 is large⌦F ( = 1) is closer to 0.5⌦H .
Figure 2 shows up and B3 a
= 0.1, 0.5, 0.9. The outflow
the fast magnetosonic point unlik
configuration case, as discussed
B3 of each flow is almost consta
unless it diverges. This means ththe←separation
Poynting flux to the fluid ene
the monopole
surface field configuration
magnetic field is almost force-fre

3.2. Parabolic configu
3.2.1. P1 mo

In this subsection, we focus on

up and n along field lines
102

102

Ψ = 0.1
Ψ = 0.5
Ψ = 0.9Ψの規格化
軸上で0最外磁力線で1

Ψ = 0.1
Ψ = 0.5
Ψ = 0.9100

101n/nnorm

up

10−2

100

10−4

10−1

10−2
10−1

10−6

100

101

102
r − rH

103

104

105

10−8
10−1

100

101

102
r − rH

103

104

105

線形コントア

Summary

一般相対論的輻射磁気流体モデル

EHT 2017の観測条件に基づく模擬観測EHT 2020の観測条件に基づく模擬観測(Chael et al. 2019)

೥

ͷ

্

δ

• Observations: limb-brightened/triple-ridge
structure, BH shadow• GRMHD simulation: density-floor problem→ cannot simulate jets

• We have constructed the steady,axisymmetric GRMHD jet model which do
not suffer the density floor problem.

• We numerically solve the force-balance

between the field lines at the separation
surface and analytically solve the windequation.

• We determine the 2D distribution of the
EM field, velocity and density in a jet.

対数コントア6

ਤ 1.

Akiyama, Asada, Hada
天文月報 2019 年 7 月号 ASTRO NEWS

Ogihara, Ogawa & TomaΑࠓ‫ޙ‬ͷ M87*ͷ‫؍‬ଌ༧૝ɻຊ‫؍‬ଌ͕࣮ࢪ͞Εͨ

Figure 1 shows ⌦F ( ) and L̂out ⌦2017 ೥ʹ͸࣮ޮ‫౓ײ‬ෆ଍ͷͨΊʹ‫ݕ‬ग़͕೉͔ͬ͠
anaration surface. ⌦F /⌦H = 0.5ΛͨδΣοτ͸ 2020 ೥ʹ͸ଊ͑ΒΕΔͩΖ͏
. = 1 are satisfie
tion L̂out ⌦F /Êoutin> 0.1, which mean that
ͷotions are consistent with the for2)& Znajek 1977)
tion (Blandfordʹʹ։ൃ͞Εͨιϑτ΢ΣΞ͕༻͍ΒΕ͕ͨ,ͦ
the monopole force-free solution dؒ
BH spin is. smaller, Ê0 is largeͷ͏ͪͷҰͭ͸ळࢁΛத৺ʹ։ൃ͞Εͨ⌦F ( = 1) is closer to 0.5⌦H .
ຊ੒Ռͷ‫ ͨͬͳͱإ‬M87*ͷը૾ͷ෮‫ʹݩ‬͸ଟ
Figure 2 shows up and B3೾
al= 0.1, 0.5, 0.9. The outflow d͘͜ͷ๜ਓ͕ࢀՃ͠, ळࢁ͕ੈ࿩ਓͷҰਓͱͯ͠࡞
the fast magnetosonic point unlik
configuration case, as discussed3)༷Λओಋͨ͠. ೔ຊ͸ຊؒɾळ‫ۀ‬൝ͱؔ࿈࿦จ
B3 of each flow is almost consta
unless it diverges. This means thun/nnormpࢁɾ஑ాΛத৺ʹεύʔεϞσϦϯάΛ༻͍ͨըthe Poynting flux to the fluid ener
the monopole field configuration,͕૾Խख๏, ͓Αͼळࢁɾా࡚ɾ৿ࢁɾ࡫ా͕த৺
magnetic field is almost force-freeͱͳͬͯͦΕΛ࣮૷ͨ͠ιϑτ΢ΣΞ SMILI Λ։ྡ

3.2. Parabolic configur
ൃͨ͠. SMILI ͸ϒϥοΫϗʔϧΛը૾Խͨ͠ࡾ
3.2.1. P1 ཁ
moIn this subsection, we focus ‫ج‬onͭͷιϑτ΢ΣΞͷҰͭͱͳΓ, ถࠃ͕ओಋ͠։

culation of the P1 model. We sho
Figure3. Two dimensional
distribution
of inupFigure
and nTaiki Ogihara,
T.
Ogawa(Univ.
of
Tsukuba),K.
Toma(Tohoku
Univ.)
andndistributionofupಈ
eht-imaging
Ͱൃͨ͠΋͏Ұͭͷιϑτ΢ΣΞ
of the P1 model. the number density byhttps://ui.adsabs.harvard.edu/abs/2021ApJ...911...34O/abstractୈ 1 ষ INTRODUCTION

8

一般相対論的M87
輻射磁気流体モデル

EHT 2017の観測条件に基づく模擬観測

線形コントアFuture Prospects

EHT 2020の観測条件に基づく模擬観測(Chael et al. 2019)• Our semi-analytic model, combined withradiative transfer calculations, may help
interpret the high-resolution VLBI
observations and understand the origin ofjetted matter.

(NRAO/NSF)

Continuing triple-ridge structureਤ 1.

• reconstruct limb-brightened structure• proper-motion / polarization• other limb-brightening jetsࠓ‫ޙ‬ͷ M87*ͷ‫؍‬ଌ༧૝ɻຊ‫؍‬ଌ͕࣮ࢪ͞Εͨ

The Astrophysical Journal, 817:131 (17pp), 2016 February 1• No one know the emission structure of jets.
Our analytic model can be adapted easierthan simulations for observed structure.
• and more…

triple-ridge structure2017 ೥ʹ͸࣮ޮ‫౓ײ‬ෆ଍ͷͨΊʹ‫ݕ‬ग़͕೉͔ͬ͠
ਤ 1.2: 1989 ೥ʹ VLA Ͱࡱ૾͞Εͨ M87 ۜՏɻ਺ Mpc ·Ͱ৳ͼΔδΣοτ͕‫؍‬ଌ͞Ε͍ͯΔɻ
M87 ͸࠷΋ৄࡉʹδΣοτߏ଄͕‫؍‬ଌ͞Ε͍ͯΔఱମͰ͋ΓɺδΣοτ‫ڀݚ‬ͷͨδΣ
οτ͸ 2020 ೥ʹ͸ଊ͑ΒΕΔͩΖ͏.

~10r_g• future EHT: jet origin/injection point

Akiyama, Asada, Hada

対数コントア

Hada et al.

HadaObserva2017ϩθολετʔϯͱ‫ݺ‬͹ΕΔ͜ͱ΋͋Δɻ(Credit:National Radio Astronomy
tory/National Science Foundation)
limb-brightened structureBlackhole Shadowʹ։ൃ͞Εͨιϑτ΢ΣΞ͕༻͍ΒΕ͕ͨ

2)δΣοτͷ‫ܗ‬ঢ়͸ଟछଟ༷Ͱ
ɺ௕͘·͙ͬ͢৳ͼΔ΋ͷ΋͋Ε͹୹͘‫͕ۂ‬Γ͘Ͷͬͨ
z = 15mas
z = 30mas
z = 5mas΋ͷ΋͋Γɺ‫؍‬ଌ೾௕ʹΑͬͯ΋มԽ͢ΔɻCyg A ͷδΣοτ͸฼ۜՏΛத৺ʹ 2 ͭͷδΣοτ͕‫ʹ޲ํٯʹ͍ޓ‬৳ͼ͍ͯΔͷʹରͯ͠ɺM87 ͷδΣοτ͸ยํʹ͔͠৳ͼ͍ͯͳ͍ɻ࣮ࡍʹ͸ɺM87 ʹ΋ 2 ͭͷδΣοτ͕ଘࡏ͢Δ͕‫͍ͯ͑ݟ‬Δํͱ͸‫ٯ‬ଆͷδΣοτ͸զʑ͔Βԕ͔͟Δ޲͖ʹߴ଎Ͱ఻೻͍ͯͯ͠ɺ૬ର࿦తͳυοϓϥʔޮՌ΍ϏʔϛϯάޮՌʹΑͬͯ‫؍‬ଌ͞Εͳ͘ͳ͍ͬͯΔͱߟ͑ΒΕΔɻͲͪΒʹ΋‫ڞ‬௨͍ͯ͠Δͷ͸δΣοτ͕฼ۜՏ͔Β·͙ͬ͢৳ͼͨઌʹ‫ڊ‬େͳ๐ঢ়ߏ଄ (ϩʔϒ) ͕ଘࡏ͢Δ͜ͱͰ͋Δɻϩʔϒ͸δΣοτ͕੕ؒ෺࣭ͱিಥ͠ɺࢄҳ͢Δ͜ͱʹΑͬͯ‫ܗ‬੒͞ΕΔͱߟ͑ΒΕ͍ͯΔɻ΄ͱΜͲ௚ઢঢ়ͷδΣοτΛۜՏத৺ʹ޲͔͔ͬͯ͞ͷ΅ΔͱɺۜՏத৺ͷ௒‫ڊ‬େϒ
Event Horizon Telescope
Hada et al. 2016ϥοΫϗʔϧ෇ۙʹߦ͖ண͘ɻϒϥοΫϗʔϧ͸Ұൠ૬ରੑཧ࿦͕༧‫͢ݴ‬Δ࠷΋‫͍ڧ‬ॏྗ৔ͷ͜ͱͰ͋Γɺೖͬͯ͠·͏ͱޫͰ͑͞΋ൈ͚ग़͢͜ͱ͕Ͱ͖ͳ͍ྖҬͰ͋Δɻ౰વɺϒϥοΫϗʔϧ͔Β͸͍͔ͳΔ෺࣭΋֎΁ग़ͯ͘Δ͜ͱ͸Ͱ͖ͳ͍ɻϒϥοΫϗʔϧ͔Β
Figure 3. VLBA+GBT 86 GHz
false-color total intensity image of the M87 jet. The image is produced by combining the visibility data over the two epochs on 2014,ͦͷ͏ͪͷҰͭ͸ळࢁΛத৺ʹ։ൃ͞Εͨ.

ຊ੒Ռͷ‫ ͨͬͳͱإ‬M87*ͷը૾ͷ෮‫ʹݩ‬͸ଟ͘ͷ๜ਓ͕ࢀՃ͠, ळࢁ͕ੈ࿩ਓͷҰਓͱͯ͠࡞

‫ۀ‬൝ͱؔ࿈࿦จ

3)Λओಋͨ͠. ೔ຊ͸ຊؒɾळ

February 11 and 26. The restoring beam (0.25 mas ×0.08 mas at PA 0°) is shown in the bottom-right corner of the image. The peak intensity is 500 mJy beam−1 and