Blazars in gamma-ray views

Blazars in gamma-ray views Challenges of AGN jets@naoj, Mitaka 19 January 2017 Masaaki Hayashida M.Hayashida et al. 2015, ApJ, in press (Institute Cosmic-ray research, (arxiv:1502.04699) the Univ. of Tokyo) Collaborators: Greg Madejski, Roger Blandford (SLAC/KIPAC), Krzysztof Nalewajko (CAMK) Katsuaki Asano (ICRR) 1

A slide from Nagai-san,,, at the workshop of 相対論的ジェットの根元と粒子加速 小研究会 @ICRR, Kashiwa, Feb. 2016! Sorry, Nagai-san,,,,! (Petropoulou, Nalewajko, MH+16)! 3C 279: Hadronic model! We (γ-ray guys)! do not care of radio-ir! we still do not care of radio,,,,! 2

A slide from Nagai-san,,, at the workshop of 相対論的ジェットの根元と粒子加速 小研究会 @ICRR, Kashiwa, Feb. 2016! Aim of this workshop:! to find consistent view!! Radio (VLBI image) AGN Jets simula5on Gamma- ray (MWL SED)

Why γ-ray is important for blazar jets SED of 3C 279 (MH, Madejski, Nalewajko, Sikora+12, ApJ, 754, 114)! jet power is dominant in γ-ray! 19 January 2017! 4

Jet energetics poynting?matter? radio (mm-vlbi)! (Kino+15,16)! poynting dominated @a few-10rs! BH! base poynting! far: matter dominated! >~104-5RS?! γ simulation magnetically driven jet (e.g., BZ mechanism)! 3DMHD simulation! (McKinney&Blandford 09)!

Jet energetics poynting?matter? Gamma-ray! radio (mm-vlbi)! minute-scale variability! à very compact! à high Γ(>50)! (Kino+15,16)! poynting dominated @a few-10rs! BH! base poynting! γ-ray? 102-3 RS! Γ>50! simulation magnetically driven jet (e.g., BZ mechanism)! (LAT collab.16, MH+16)! far: matter dominated! >~104-5RS?! γ

Jet energetics poynting?matter? Gamma-ray! radio (mm-vlbi)! minute-scale variability! à very compact! à high Γ(>50)! (Kino+15,16)! poynting dominated @a few-10rs! BH! (LAT collab.16, MH+16)! base poynting! far: matter dominated! >~104-5RS?! γ-ray?! simulation magnetically driven jetsimulation! 3DMHD (e.g., BZ mechanism)! γ Γ>50! high-compton dominance! à matter dominated jet! (McKinney&Blandford 09)!

Jet energetics poynting?matter? Gamma-ray! radio (mm-vlbi)! minute-scale variability! à very compact! à high Γ(>50)! (Kino+15,16)! poynting dominated @a few-10rs! BH! (LAT collab.16, MH+16)! base poynting! matter dominated! γ-ray? <102RS?! R γ 10Γ>50! 2-3 simulation magnetically driven jetsimulation! 3DMHD (e.g., BZ mechanism)! S! high-compton dominance! à matter dominated jet! (McKinney&Blandford 09)!

Outline of this talk what is the dominant energy component in the jets?! where is the gamma-ray emission site?! 1. 3C 279: Hadronic γ-ray origin model! 2. PKS 2155-304: NuSTAR observation! electron distribution (γ min )! what is the acceleration mechanism?! 3. RXJ 1136.5+6737: New VHE BL Lac! stochastic (Fermi-II) acceleration model! 4. Gamma-ray and radio connections for AGN jets!! Jan. 14, 2016 CTA-Japan workshop! Masaaki Hayashida (ICRR, U. Tokyo)! 9

Blazars in γ-ray views: 3C 279 high-compton dominance (L sync << L IC )! matter-dominated (u B /u e ~ 10-4, Asano&MH15)! fast variability: t var ~5 min opening angle: θ o =1/Γ! BH! emission size (r) ~ δct var /(1+z) ~ 3x10 14 (δ/50) cm à a few R S! distance from BH (R):10 16 (Γ/50) 2 (Γθ o ) -1 cm à 100(Γ/50) 2 R S! Very high luminosity: 10 49 erg s-1! need dense seed photon (Broad line region: R < 10 17 cm)! θ o R r (LAT collab.16, MH+16)! (MH+16)! 10

Blazars in γ-ray views: 3C 279 high-compton dominance (L sync << L IC )! matter-dominated (u B /u e ~ 10-4, Asano&MH15)! fast variability: t var ~5 min opening angle: θ o =1/Γ! BH! emission size (r) ~ δct var /(1+z) ~ 3x10 14 (δ/50) cm à a few R S! distance from BH (R):10 16 (Γ/50) 2 (Γθ o ) -1 cm à 100(Γ/50) 2 R S! Very high luminosity: 10 49 erg s-1! need dense seed photon (Broad line region: R < 10 17 cm)! Hadronic origin γ-ray emission! θ o R r (LAT collab.16, MH+16)! (MH+16)! 11

Hadronic origin γ-ray scenario: 3C 279 (Petropoulou, Nalewajko, MH+17, MNRAS in press, arxiv:1612.05699)! Base code: Petropoulou & Dermer 16, ApJL! GeV γ-ray origin: proton synchrotron (need less power but higher proton energies than photomeson (pγ) origin)! Data : Orbit-D (red: simultaneous UV, X-ray and γ-ray data)! 100PeV! (LAT collab.16, MH+16)! (MH+16)! 12

Hadronic emission origin : 3C 279 Α. δ=20, B=2.2kG, Β. δ=50, B=0.8kG, <u p > ~ 8e4 erg/cm 3 (u B /u p ~1), <u p > ~ 800 erg/cm 3 (u B /u p ~4)! P jet =8e47 erg/s (~14Mc 2 )! P jet =1e48 erg/s! to much,,,! internal γγ absorption (EM cascade)! target γ: e-/p-sync! à unavoidable,,,! internal γγ absorption (EM cascade)! target γ: BLR photons! 13

Hadronic emission origin : 3C 279 Α. δ=20, B=2.2kG, Β. δ=50, B=0.8kG, <u p > ~ 8e4 erg/cm 3 (u B /u p ~1), <u p > ~ 800 erg/cm 3 (u B /u p ~4) P jet =8e47 erg/s (~14Mc 2 )! P jet =1e48 erg/s! Basically, hadronic origin model is not favored for the GeV minutescale flare of 3C 279!! but, if the location is well outside of BLR ( 10 18 cm ~10 4 R s )! (or very dim BLR photon field)! but still B >100 G,! we can avoid the internal γγ absorption then, it can be possible.! internal γγ absorption (EM cascade)! target γ: BLR photons! 14

Blazars in γ-ray views high-compton dominance (L sync << L IC )! matter-dominated (U B /U e ~ 10-4, Asano&MH15)! fast variability: t var ~5 min opening angle: θ o =1/Γ! BH! emission size ~ δct var /(1+z) ~ 3x10 14 (δ/50) cm à a few R S! θ o R r distance from BH:10 16 (Γ/50) 2 (Γθ o ) -1 cm à 100(Γ/50) 2 R S! Very high luminosity: 10 49 erg s-1! need dense seed photon (Broad line region: R < 10 17 cm)! Hadronic emission origin! co-existence of low- and high-energy electrons?! N e (γ) 1 γ min! γ - q for γ-ray! γ max! ~10 3-4! γ 31 May 2016 JETS2016 at Malaga! Masaaki Hayashida (ICRR, U. Tokyo)! 15

Blazars in γ-ray views high-compton dominance (L sync << L IC )! matter-dominated (U B /U e ~ 10-4, Asano&MH15)! fast variability: t var ~5 min opening angle: θ o =1/Γ! BH! emission size ~ δct var /(1+z) ~ 3x10 14 (δ/50) cm à a few R S! distance from BH:10 16 (Γ/50) 2 (Γθ o ) -1 cm à 100(Γ/50) 2 R S! Very high luminosity: 10 49 erg s-1! need dense seed photon (Broad line region: R < 10 17 cm)! Hadronic emission origin! co-existence of low- and high-energy electrons?! 31 May 2016 JETS2016 at Malaga! Masaaki Hayashida (ICRR, U. Tokyo)! 16 N e (γ) 1 θ o R γ - q r for γ-ray! γ max! ~10 3-4! γ min! can reduce power of the matter! γ

PKS 2155-304 (HBL: z=0.116) Well-known southern blazar! One of three best-studied HBL-type blazars (along with Mrk) (ß à FR-I :M87) M BH ~ 10 9 Msolar! minute-scale variability in TeV! Our MWL observations: 2014 April! NuSTAR (3-79 kev):! first observation of this source! XMM-Newton: (0.5-10 kev)! Swift (UVOT):! Fermi-LAT : (0.1-10 GeV)! (HESS Coll. 08)! effective area! 17

X-ray spectrum in a very low state NuSTAR : 2014/04/22-23 (44.9ks)! 2 power-law (PL) model is favored: Γ soft : 3.03 +1.1-0.25, Γ hard : 1.85±0.70! (χ 2 /dof: 304/293 [PL] à 292/291 [2PLs])!! XMM + NuSTAR spectra! Model: logpar + (hard) power low! α(@2kev): 3.04 +0.16-0.14, β=0.3+0.2-0.1 + Γ pl : 2.2±0.4! (χ 2 /dof: 2629/2492 [w/o PL] à 2546/2490 [with PL])! F 2-10 kev ~ 1.1x10-11 erg/cm 2 /s (~1/3 of typical low state)! (Madejski,,,MH+16, ApJ)! XMM (pn) + NuSTAR (FPMA+FPMB)! significant hard tail! N H : Galactic value (1.42x10 20 cm -2 )! Masaaki Hayashida (ICRR, U. Tokyo)! 18

MWL SED and modeling Fermi-LAT: (>0.1 GeV)! 2014/04/17-27! Γ γ =1.71±0.15 F >0.1GeV =(8±2)x10 8 (ph/cm 2 /s)! TS=196! Modeling: one-zone SSC! R=1.3x10 16 cm, Γ j =15, B =0.5 G! Electron: γ min =1, (at most 100) p 1 =2.2, γ br =2.6x10 4, p 2 =3.8, γ max ~10 7! log 10 F [erg s -1 cm -2 ] -9-10 -11-12 NuSTAR + XMM (MJD 56405) Fermi/LAT (MJD 56400-56410) Swift/UVOT The hard-x-ray excess is consistent with the low-energy Inverse-Compton tail! L B ~3.8x10 43, L e ~3.7x10 44, à L B /L e ~ 0.1 (matter-dominated)! (Madejski,,,MH+16, ApJ)! PKS 2155-304 -13-3 -2-1 0 1 2 3 4 5 6 7 8 9 10 11 12 log 10 E [ev] see the case of Mkn 421 (Kataoka+16)! 19

Outline of this talk what is the dominant energy component in the jets?! where is the gamma-ray emission site?! 1. 3C 279: Hadronic γ-ray origin model! 2. PKS 2155-304: NuSTAR observation! electron distribution (γ min )! what is the acceleration mechanism?! 3. RXJ 1136.5+6737: New VHE BL Lac! stochastic (Fermi-II) acceleration model! 4. Gamma-ray and radio connections for AGN jets!! radio galaxy (very briefly)! Jan. 14, 2016 CTA-Japan workshop! Masaaki Hayashida (ICRR, U. Tokyo)! 20

Open questions in Blazar Emission 1. Index harder than 2 for the electron injection spectrum. Kino, Takahara, Kusunose 2002! (see also 3C279, MH+15)! 2. Lower maximum energy! the Bohm factor should be ~10-4 (Inoue&Takahara 96) 3. Too sharp break in the electron spectrum. Compared to the cooling break, the index changes seem large. can be hard to be generated by simple shock acceleration! magnetic reconnection but will efficiently work and generate hard spectra in matter-dominated conditions?! stochastic (Fermi-II) acceleration still a few studies. e.g.,! à Mkn421 (Asano+14) à 3C 279 (Asano&MH+15)!

RX J1136.5+6737 (z=0.1342) High-frequency peaked BL Lac objects (HBL)! RA, Dec: J2000 = 11 h 36 m 30.1 s, 67 37 04! 7th brightest BL Lac in the MAXI/GSC (4-10 kev) 37-month catalog! Swift-BAT (14-195 kev) source (in 21 HBLs) : index: 2.3±0.4! Fermi-LAT: both in 3FGL and 1FHL : Γ >100 MeV = 1.72±0.08! But, very faint in radio and optical bands (Lindfors+16)! MAGIC-I : ULs (>230 GeV): 5.7% C.U. (Albert+08)! R-band [mjy]! 32 northern VHE blazars! (the 2nd MAXI/GSC catalog: Hiroi, Ueda, MH+13, ApJS)!! 9 sources (among 13) are known TeV HBL! 1ES0502+675! 1ES1426+428! RGB0847+115! this source! 1ES0229+200! extremehbl -like! (Lindfors+16)! radio (15 GHz) [Jy]!

Discovery of VHE emission! MAGIC observations! 2014 Jan. May (32 hr.)! 1.3±0.3 % Crab flux (>300 GeV)! (MH+15 ICRC, MAGIC collab. in prep)! no significant variability! preliminary!

SSC with stochastic electron acceleration Geometry: shell structure! in conical jet! θ=1/γ! B =B 0 (R/R 0 ) -1! (Model: Asano+2014, ApJ 784, 64)! <free parameters>! D(ε e ) = D 0 ε e 2 (energy (ε) diffusion coefficient)! n e,0 (electron injection rate), Γ, B 0, R 0! electron spectrum! n (ε e ) ε e -1.0! preliminary! u B /u e = 0.17: matter dominated!

Jet energetics:poynting?matter? BH! base:poynting! where it is?! far: matter dominated! γ-ray?? γ 3DMHD simulation! Gamma-ray emission:! Problems in γ-ray observations! Poor imaging capability! <from observations>! à hard to locate the γ-ray small emission region! emission site! matter-dominated! very high luminosity (10 49 erg/s)! <possible other solutions>! only a part of jet cross section?! very narrow jet? re collimation shock?!

Jet energetics:poynting?matter? BH! base:poynting! where it is?! far: matter dominated! γ-ray?? γ 3DMHD simulation! Advantage of radio observations! best imaging capability!!! important to understand! the connection! Problems in γ-ray observations! Poor imaging capability! à hard to locate the γ-ray emission site! simulations! <my question>! what do you expect (need)! for γ-ray observations?!

knot ejection/passage? Jorstad+16! 43 GHz VLBI! 2007 Jun. to 2013 Jan.! 30-40 sources with >2000 images! 52 γ-ray flare! 83% γ-ray flares accompany knot passages of core! 65% of knot passages are not accompanied by γ-ray flare.! Are there correlation or not?! How much is chance coincidence?! How much is the efficiency? (any biases for searching knots?)! How much of errors in the analysis?! I would like to know statistical arguments in more details!!.! 27

Spine-sheath jet? a slide from Tahakara-san at 相対論的ジェットの根元と粒子加速 小研究会 ( relativistic jet base and particle acceleration )@ICRR, Kashiwa, in Feb. 2016! do we really observe the same jet in radio and γ-ray?! message from Takahara-san! need to observe! fast spin by radio! slow sheath by γ-ray! radio galaxies! 28

NGC 1275 NGC 1275 Previously detected by MAGIC (~3% Crab, Aleksic+14) and VERITAS (~1% Crab, Benbow+15)! flux enhancement at the end of Oct. 2016: ~15% Crab! [VERITAS results (variation in daily scale?)]! MAGIC Atel#9689! VERITAS Atel#9890! <Fermi-LAT LC>! huge flare on Dec.31 2016: ~1.5Crab (2nd, 3rd Jan. 0.7 Crab)! MAGIC Atel#9929, VERITAS Atel#9931! >100 MeV! 1-day bin! 29

M87 MAGIC observations in 2012-2015! low states! 2017 MAGIC observation plans.! Dense monitoring for the April campaign has approved (PI: Daniel Mazin, ICRR)! Usual monitoring! 30

Summary New results of blazars in the γ-ray view.! 1. Hadronic origin for the 3C 279 minute-scale flare! not favored (possible if outside BLR > 10 4 R S )! à matter-dominated jet (σ 10-4 in the leptonic origin)! 2. PKS 2155-304: MWL observations with NuSTAR! hard tail in the hard X-ray, constraint γ min (at most ~100)! à matter-dominated jet (σ~0.1)! 3. RXJ 1136.5+6737: New VHE BL Lac by MAGIC! Hard electron spectrum, stochastic accelerations! à matter-dominated jet (σ~0.1)! Still we do not reach consistent views of jets,,,! In γ-ray: σ <<1, t var,min ~5 min, z diss ~10 2-4 R S, Γ>50, L max ~10 49 erg/s! Gamma-ray and radio connection is very important!!! intensive radio-γ-ray observations for M87 is scheduled. 31 May 2016 JETS2016 at Malaga! Masaaki Hayashida (ICRR, U. Tokyo)! 31