agn inflow/outflow with ska
DESCRIPTION
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 PresentationTRANSCRIPT
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)
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.
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
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
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?