1. AGN 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

2. Members N. 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)

3. Outline 1. Why AGN with SKA ? 2. AGN outflow 3. AGN inflow 4. Summary

4. Because it will have VLBI-order resolution (D~3000km) with sub-μ Jy revel sensitivity! Wilkinson 2004 Why AGN with SKA?

5. Key points for AGN science with SKA 1. Wide-band spectra 2. Searching for very faint radio emission 3. Synergy with ALMA + other telescope

6. 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

7. 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

8. δ ： Non-thermal energy /Total energy Hybrid populations: Relativistic Maxwellian + Power law γ: Lorentz factor Electron number distribution Power-law index

9. Plasma temperature kinetic energy of AGN Jets ⇒ Thermal energy ＠ hot spots Kino& Takahara 04 5.29.2 e.g., Blandford & McKee 1976, Kino & Takahara 2004 “Shock jump conditons” Assumption: 2-Temperature plasma Bulk Lorentz factor

10. Thermal (black) Non-thermal (blue) Optically thick Optically thin Results: Synchrotron spectrum Thermal bump @10-100MHz Hot spot

11. Exploring thermal synchrotron with LOFAR/SKA ◆ Frequency ：＜ 500MHz ⇒ LOFAR(10-250MHz), SKA(Low-band) ◆ Spatial resolution ： Spatial resolution LOFAR ～ 2 arcsec @250MHz SKA ～ 0.1 arecsec @250MHz Typical hot spots size Cygnus A (z=0.057) 2-3 arecsec 3C295 (z=0.46) 0.1-0.2 arcsec 3C295 CygnusA

12. 3C295 lobe z=0.46 size=20kpc B=4 x10 -4 G Sign of thermal emission ? Thermal component Non-thermal component VLA@ 74MHz 2 0 6 7 8 9 10 data:Taylor & Perley(1992)

13. AGN inflow - Imaging Accretion Disk-Corona - Searching for AGNs in ULIRGs/BCDs Kawaguchi, Imanishi, Kawakatu, Umemura, Doi, Kameno, Hirashita

14. 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 body Cyc-syn emission - Size : ~ 300 R s - Brightness temperature: Te~T b ~10 9 K for ν < 20GHz - Targets : Nearby Seyferts * ~ 20GHz Log νL ν [erg/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

15. 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

16. 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?

17. 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 ν 1/3 - BCD: ongoing SF, metal poor - No evidence of bright AGNs (optical and X-ray) How about Faint AGNs ? Starburst (Free-free) PI:Kawakatu L RIAF,max =2x10 38 erg/s M BH =800M sun

18. 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.

19. Thanks for your attention! 감사 합니다

20. Back-up slides

21. 3C295 lobe z=0.464 How about thermal + Non-thermal emission model ? This model cannot reproduce the observational data…

22. Thermal + 2-step acceleration γ max γ nth Fermi acceleration Fermi acceleration γ -2.5 Thermal γ br Injection region γ 0 Lorentz factor γ N(γ) Absorption of electromagnetic waves emitted at the harmonic of cyclotron frequency of cold plasma

23. Min. of the electron number density Relativistic Shock Junction (Blandford & McKee 1976) Stationary hot spot. i.e., Injection by jet=sideways escape min. n e by NT. electrons in the hot spot

24. Bulk Lorentz factor Γ j =O(10) → Thermal bump@10-100MHz Electron temperature (θ e )-dependence

25. Electron acceleration efficiency （ δ ） -dependence Amplitude of thermal bump → Electron acceleration efficiency Non-T(black) (Ito+08)

26. Magnetic field(B)-dependence Larger B hs ⇒ peak frequency is higher.

27. 3C295 lobe z=0.464 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 Viewing angle ： 63° Consistent with type 2 AGN Thermal+2-Step Acceleration Model

28. Prediction: Radio spectra from hot spot in 3C295 LOFAR, SKA? Taylor & Perley(1992)

29. 3C295 lobe z=0.464 Thermal+2-Step Acceleration Model VLA@ 74MHz

30. Pure non-thermal cases

31. FRII range

32. Ukrainian T-shaped Radio telescope, second modification (UTR-2) Resolution: 40’x 40’ Frequency: 10-30MHz Collective area: 150,000 m 3

33. E max E min Non-thermal E -s Non-thermal E -sthermal emission e+e+ e-e- e+e+ e-e- p e-e- Thermal electron or thermal/non-thermal proton are needed!  Missing Power problem Electron energy Can we observe thermal emission from cocoon/hot spots? Total pressure of cocoon e.g., Ito+08

34. 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…

35. 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 ρ ext A h v h 2 =const deceleration acceleration

36. R=200pc R=2.2 kpc R=22 kpc Other Candidates ?

37. O’Dea +1990 Interesting GPS sources

38. Multiple IMBHs in BCD? BCD (~100pc) IMBHs Hirashita & Hunt +06, Hirashita & Sakamoto +10 You may detect RIAF emission from multiple IMBHs. Spatial resolution ： 0.01” :1pc@10Mpc, 0.1”: 10pc@10Mpc Bondi accretion

39. SED of young BCDs II ZW 40 (age ~ 3Myr) VLA(3-4’’) SMA (5’’) Hirashita 2011 Free-Free AGN L RIAF,max =2x10 38 erg/s M BH =800M sun, α=0.1 ν 1/3 SB (Free-free) ν -0.1 VLA(0.1’’) ALMA 0.6 SKA dust

40. Maximum Luminosity of RIAF 制動放射∝密度の２乗 Log(surface density) Log(Mass accretion rate) No solution of RIAF e.g., Balbus & Hawley 1991: Machida et al. 2000

41. Low luminosity AGN SED : SgrA* ν 4/3 Peak frequency ： Peak luminosity ： Mahadevan 97

42. What are AGNs? Accretion disk SMBH ~10 8-9 M  Relativistic Jet v ~ c Compact (~ 100 AU) and luminous (~ 10 46-47 erg/s) objects cf. typical galaxies 10 44 erg/s @ kpc ～ 60 kpc AGN jets: Biggest ( ～ 100kpc) and powerful relativistic plasma fountain in the universe.

43. 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?

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