agn inflow/outflow with ska

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AGN inflow/outflow AGN inflow/outflow with SKA with SKA Nozomu Kawakatu (University of Tsukuba) On behalf of SKA-Japan AGN sub-WG Workshop on East-Asia collaboration for SKA@KASI, Nov.30-Dec. 2 2011 (C) J. McKean Cygnus A at 240 MHz with LOFAR

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Cygnus A at 240 MHz with LOFAR. AGN inflow/outflow with SKA. (C) J. McKean. Nozomu Kawakatu ( University of Tsukuba ) On behalf of SKA-Japan AGN sub-WG. Workshop on East-Asia collaboration for SKA@KASI, Nov.30-Dec. 2 2011. Members. N. Kawakatu (Univ. of Tsukuba) M. Kino (NAOJ) - PowerPoint PPT Presentation

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AGN inflow/outflow with SKAAGN inflow/outflow with SKA

Nozomu Kawakatu (University of Tsukuba)On behalf of SKA-Japan AGN sub-WG

Workshop on East-Asia collaboration for SKA@KASI, Nov.30-Dec. 2 2011

(C) J. McKean

Cygnus A at 240 MHz with LOFAR

MembersN. Kawakatu (Univ. of Tsukuba)M. Kino (NAOJ) T. Kawaguchi (Univ. of Tsukuba)A. Doi (ISAS/JAXA)S. Kameno (Kagoshima Univ.)T. Hayashi (Univ. of Tokyo) H. Ito (Yukawa Institute for Theoretical Physics) M. Imanishi (NAOJ/Subaru) H. Nagai (NAOJ) M.Umemura (Univ. of Tsukuba)

Outline1. Why AGN with SKA ?2. AGN outflow3. AGN inflow4. Summary

Because it will have VLBI-order resolution (D~3000km) with sub-μ Jy revel sensitivity!

Wilkinson 2004

Why AGN with SKA?

Key points for AGN science with SKA

1. Wide-band spectra2. Searching for very faint radio emission3. Synergy with ALMA + other telescope

AGN outflow・ Emission from AGN jets remnants - Relativistic thermal emission (NK & Kino, in preparation)- Non-thermal emission (Ito’s talk) ・ Young RGs and BAL QSOs (Hayashi’s talk)

Kino, Ito, Hayashi, Nagai, Kawakatu

AGN jets remnants

Hot spots: reverse shock

Shell :forward shock

AGN jets remnants is good laboratory to reveal the physics of a collisionless shock.

AGN jets ⇒ Collisionless shock

δ : Non-thermal energy /Total energy

nth

Hybrid populations: Relativistic Maxwellian + Power law

52p .

2min/ ~ekT m c

γ: Lorentz factor

Electron number distribution

Power-law index

Plasma temperature

kTnc hs2

hsj ,,

ehsp2

hspj kTnc ,,

kinetic energy of AGN Jets⇒Thermal energy @ hot spots

Kino& Takahara 04

5.2 9.2

e.g., Blandford & McKee 1976, Kino & Takahara 2004

“Shock jump conditons”

Assumption: 2-Temperature plasma

jBulk Lorentz factor

6 3 31[ ], 10 [ ], 10 [ ]hs nth hskpc cm GR N B

10

0.01

p

2 7 22 , 34.2 10 [ ]p b hs HzB Thermal (black)

Non-thermal (blue)

Optically thick Optically thin3310

3210

3110

3010610 710 810 910

Results: Synchrotron spectrum

Thermal bump@10-100MHz

j~ 2

Hot spot

Exploring thermal synchrotron with LOFAR/SKA

◆ Frequency :< 500MHz ⇒ LOFAR(10-250MHz), SKA(Low-band)◆ Spatial resolution :

Spatial resolutionLOFAR ~ 2 arcsec @250MHzSKA ~ 0.1 arecsec @250MHz

Typical hot spots size Cygnus A (z=0.057) 2-3 arecsec3C295 (z=0.46) 0.1-0.2 arcsec

3C295 CygnusA

3C295 lobe z=0.46size=20kpcB=4 x10-4 G

Sign of thermal emission ?

Thermal component

Non-thermal component

VLA@74MHz2

06 7 8 9 10

10th nthN N① th nth BU U U ②data:Taylor & Perley(1992)

AGN inflow

- Imaging Accretion Disk-Corona- Searching for AGNs in ULIRGs/BCDs

Kawaguchi, Imanishi, Kawakatu, Umemura, Doi, Kameno, Hirashita

9 10 11 12 13 14 15 16 17 18 19

46

45 44

43 42

41

40

39

38 Log ν [Hz]

Disk black bodyCyc-syn emission

- Size : ~ 300 Rs - Brightness temperature: Te~Tb ~109K for ν < 20GHz- Targets : Nearby Seyferts

* ~20GHz

Log

νL

ν [e

rg/s

]

SKA

Kawaguchi +01

Imaging Accretion Disk-Corona

Higher freq. is essential to resolve it. ⇒ SKA@high-band

ALMA

Accretion disk

BH

Corona

PI:Kawaguchi

AGN or Starburst in ULIRGs?

Which is the energy source of ULIRGs ?Extremely powerful energy sources behind dust @z <0.1

AGN: compact Starburst: extended

★AGN SB

High surface brightness radio core emission = AGN

IR-spectroscopy study (Imanishi+06,07,08,09)

?

Observations with high spatial resolution at >5 GHz avoiding FFA & SSA are required. ⇒ SKA@high-band

PI:Imanishi

Japanese VLBI Network (JVN)

Noise level: ~ 0.2mJy (10 stations, 4hrs)Spatial resolution: ~3mas@8GHz

Radio bright ULIRGs ( > 5mJy)It would be possible to distinguish between AGNs and starbursts.

Radio faint ULIRGs (< 5mJy)Collaboration with KVN +CVN?

AGNs in Blue Compact Dwarfs?

II ZW 40

VLA(3-4’’)

SMA (5’’)

Hirashita 2011

AGN (RIAF)

Starburst (Free-free) ν-0.1

SKA

0.6

VLA(0.1”) Beck+02

Spectral index is the key to distinguish them. ⇒ SKA@mid-band frequency (1-15 GHz)

ALMA

ν1/3

- BCD: ongoing SF, metal poor- No evidence of bright AGNs (optical and X-ray)

How about Faint AGNs ?

Starburst (Free-free)

PI:Kawakatu

LRIAF,max=2x1038 erg/s MBH=800Msun

1. AGN outflow- Relativistic thermal emission Thermal bump @10-100MHz : LOFAR/SKA → Electron temperature & electron acceleration efficiency “Revealing physics of a collisionless shock”- Non-thermal emission from AGN shells (Ito’s

talk)- Young RGs and BAL QSOs (Hayashi’s talk)2. AGN inflow- Imaging nearby Accretion Disk-Corona- Searching for faint AGNs in ULIRGs /BCDs

Summary

If you are interested in above topics , please join us.If you are interested in above topics , please join us.

Thanks for your attention!감사 합니다

Back-up slides

10],G[100.4B],cm[109.1N 4lobe

33th

027.0

001.0

3C295 lobe z=0.464

How about thermal + Non-thermal emission model ?

This model cannot reproduce the observational data…

Thermal + 2-step acceleration

γmaxγnth

Fermi acceleration

Fermi acceleration

γγ -2.5-2.5

ThermalThermal

γbr

Injection region Injection region γγ00

Lorentz factor γ

N(γ

)

Absorption of electromagnetic waves emitted at the harmonic of cyclotron frequency of cold plasma

Min. of the electron number density

Relativistic Shock Junction (Blandford & McKee 1976)

Stationary hot spot. i.e.,Injection by jet=sideways

escape min. ne by NT. electrons in the hot spot

c

jjNTHS

c

jjHS

c

jjjjc

V

tvA

V

tvA

V

tvA

,

6 31[ ], 10 [ ] 10 [ ]-3hs nth hskpc cm GR N B

Bulk Lorentz factor Γj=O(10) → Thermal bump@10-100MHz

e j~ 2

0.01 30e

5e

3010910810710610 1010

3110

3210

3310

3410

10e

Electron temperature (θe )-dependence

10e

7 31[ ], 10 [ ], 10 [ ]-3hs nth hskpc cm GR N B

Electron acceleration efficiency ( δ ) -dependence

Amplitude of thermal bump → Electron acceleration efficiency

3010910810710610

3110

3210

3310

0.001

0.01

0.1

0.1 0.01

Non-T(black)

(Ito+08)

Magnetic field(B)-dependence

Larger Bhs ⇒ peak frequency is higher.

61[ ], 10 [ ], 10-3hs nthkpc cm eR N

3010910810710610 1010

3110

3210

3310

3410

3510

400,10],G[100.4B

],cm[104.5)(N],cm[109.1N

br4

lobe

35brnth

33th

3C295 lobe z=0.464

]kpc[20R lobe Projected size

注)熱的バンプ磁場、熱的電子数、温度大→斜め右上方向にシフトローブのサイズ大→ほぼ真上にシフト

]kpc[5.22R lobe

Viewing angle : 63°Consistent with type 2 AGN

Thermal+2-Step Acceleration Model

1 3 3 3

3

1.9 10 [ ], ( ) 5.4 10 [ ],

2.1 10 [ ], 10, 400, 2.5

th nth br

HS br

N cm N cm

B G p

Prediction: Radio spectra from hot spot in 3C295

LOFAR, SKA?

Taylor & Perley(1992)

5.2p,400,10],G[100.4B

],cm[104.5)(N],cm[109.1N

br4

lobe

35brnth

33th

3C295 lobe z=0.464

Thermal+2-Step Acceleration Model

]kpc[5.22R lobe

VLA@74MHz

1R hsplpl,

30min

100min

300min

]G[10B],cm[10N],kpc[1R 3hs

33thhs

Pure non-thermal cases

1th,

b2minmin

FRII range

FRII range

Ukrainian T-shaped Radio telescope, second modification (UTR-2)

Resolution: 40’x 40’Frequency: 10-30MHzCollective area: 150,000 m3

EmaxEmin

Non-thermal

Non-thermal EE -s-s

thermalthermal

emission e+e-

e+

e-p

e-

Thermal electron or thermal/non-thermal proton are needed!

Missing Power problem

BNT

BNTNT

pptot PPPPPPPP

Electron energy

Can we observe thermal emission from cocoon/hot spots?

Total pressure of cocoon

e.g., Ito+08

D=1Gpc

 Emissions from Shells Associated with Dying Radio galaxies

SKA@mid & high band + ALMA

Physics of forward shock

:electron acceleration efficiency

Ito’s talk

In general, AGN shell is dim, but…

Fate of expanding radio bubbles

Its fate is governed by v_h @~kpc. i.e., Supersonic or Sub-sonic? SKA can fill the gap mini-lobes and large FR I and IIs.

Kawakatu, Nagai, Kino, 2008

ρext Ah vh2=const

dece

lera

tion

acceleration

R=200pc R=2.2 kpc

R=22 kpc

Other Candidates ?

O’Dea +1990

Interesting GPS sources

Multiple IMBHs in BCD? 

3

32ISM

sun2

BH42

E

Bondibondi s/km40

v

cm10

n

M10

M105.7

cL

Mm

BCD (~100pc)

IMBHs

33ISM cm10n Hirashita & Hunt +06, Hirashita & Sakamoto

+10

RIAF.max

3

sun

BH2bondi m~

s/km40

v

M400

M103m

sun7

*

sun6

gas

M10M

M10M

sun

BH3

M400

Ms/erg~L103L 38

EddRIAF 10

You may detect RIAF emission from multiple IMBHs.

Spatial resolution : 0.01” :1pc@10Mpc , 0.1”: 10pc@10Mpc

Bondi accretion

SED of young BCDs

II ZW 40 (age ~ 3Myr)

VLA(3-4’’)

SMA (5’’)

Hirashita 2011

Free-Free

AGNLRIAF,max=2x1038 erg/s MBH=800Msun, α=0.1

ν1/3

SB (Free-free)ν-0.1

VLA(0.1’’)ALMA

0.6

SKA

dust

Maximum Luminosity of RIAF

2cMM

M1.0L

RIAFmax,RIAF 2

2

c

L3M: Edd

RIAFmax,

0.1for EddmaxRIAF, L103L 3

制動放射∝密度の2乗

RIAFmax,M

M

2M

-advvis QQ

-radvis QQ

Log(surface density)

Log

(Mas

s ac

cret

ion

ra

te)

maxNo solution of RIAF

0.1(MRI) 01.0e.g., Balbus & Hawley 1991: Machida et al. 2000

Low luminosity AGN SED : SgrA*

ν4/3

Peak frequency :Peak luminosity :

2/12/1 mm 2/32/1 mm

Mahadevan 97

What are AGNs?

Accretion disk

SMBH ~108-9M

Relativistic Jet v ~ c

2AGNL Mc

Compact (~ 100 AU) and luminous (~ 1046-47 erg/s) objects cf. typical galaxies 1044erg/s @ kpc

~60

kpc

AGN jets: Biggest ( ~ 100kpc) and powerful relativistic plasma fountain in the universe.

Japanese VLBI Network (JVN)

Noise level: ~ 0.2mJy (10 stations, 4hrs)Spatial resolution: ~3mas@8GHz

Radio bright ULIRGs ( > 5mJy)It would be possible to distinguish between AGNs and starbursts.

If these are not enough (FFA,SSA), we may need observations at 22GHz. Collaboration with KVN +CVN?

2500

km

5000 km