Chuck Dermer (NRL)Naval Research Laboratory, Washington, DCcharles.dermer@nrl.navy.mil

Recent work withMatteo Cerruti (CfA), Catherine Boisson (LUTH),

Andreas Zech (LUTH), Benoît Lott (CEN Bordeaux),

Hajime Takami (KEK), Kohta Murase (IAS)

Mid-Atlantic Radio-Loud AGN Meeting, 27 September 2013 , STScI

Radio-Loud AGNs as the Sources of the Ultra-High Energy Cosmic Rays

Standard Blazar Model

Leptonic jet model: Nonthermal synchrotron paradigm Associated SSC and EC component(s)

Target photon sources: Accretion-disk radiation Broad-line region radiation IR radiation from molecular torus

Accretion Disk

SMBH

RelativisticallyCollimated Plasma Jet

Observer

BLR clouds

Dusty Torus

Ambient Radiation Fields

GeV spectral breaks in FSRQs, LSP/ISP blazars

– 3C 454.3

Rapid variability– Shorter than the BH dynamical timescale

VHE radiation from FSRQs– 3C 279, 4C +21.35, PKS 1510-089

Two classes of BL Lac objects– Strongly variable (Mrk 421, Mrk 501, PKS 2155-304)– Weaky variable (1ES 0229+200, 0347-121, 1101-232)

EBL/IGMF relationship– Extra component in EBL deabsorbed blazar SED (Finke

et al. 2010)– Stecker-Scully relation– Measuring the IGMF

Five Major Fermi/IACT Blazar Discoveries

Equipartition Blazar Modeling

1. Use log-parabola function for electron distribution

2. From observations of Lsyn, syn, and tvar, derive parameters for B, Doppler factor D, pk , r’b

4. Use numerical model to adjust parameters to fit data, implying energy density of the external radiation field and (minimum) absolute jet power

5. Constrain location of the -ray emission site

6. Explain GeV cutoff in FSRQs and LSP/ISP blazars

3-parameter model: amplitude K, curvature b,p

Equipartition Relations

1. Assume (3-parameter) log-parabola function for electron distribution

1. Use observables and equipartition relations to derive , B, p , R’b

)1( , snucpeBtot uu

4203

4DpkeBT

syns NucL

BsssDbkins uuucrL ,4 42

)]([,,)( 2log2pkepk

pk

xbe NKxxKN

Equipartition Relation:

8,

22B

uuV

Ncmu BBe

b

pkoee

2

2

3pk

crs B

B Spectral Relation:

1eWhat does equipartition mean?

vDb tcr bgives monoenergetic electron specrum

log-parabola width

Solution to System of Equations

16/78/14

4/18/114

16/348

4/1

2

8/1

var

16/1

7546

3

5.173

2

s

e

e

eTscr

s

sD t

L

cmt

B

c

L

8/54

8/314

16/148

4/3

16/13

0.5)(tL

GBe

s

Minimum jet power

16/3

4/1

16/148

8/514

8/34523

s

epk L

t

Dermer et al. (2012)

Corrections for b ≠

FSRQ Modeling

1 GeV

Syn vs. EC beaming effect (Dermer 1995)

FSRQ Modeling: Dependence on b and tvar

1 GeV

BL Lac Modeling

Similar to SEDs of Mrk 421, Mrk 501, but not PKS 2155-304, 1ES 0229+200, 1ES 1101-232. Contrary to flaring periods in Mrk 501

3C 279 Model Data from Hayashida et al. (2012)

3C 279 Model Data from Hayashida et al. (2012)

External-field energy densities

– Normally = 0.1, implies that emission region near outer edge of the BLR, ~0.1-0.3 pc from SMBH

Jet Model– Colliding shells

Jet Power– Less than Eddington luminosity for MSMBH = (3-8)x108

Mo

Particle Acceleration– Second-order Fermi acceleration

Extra high-energy spectral component

Implications

3246

2003.0

4 cmerg

R

L

cR

Lu

pc

IRIR

Multi-line model Thermal spectrum for dust

radiation

Code improvementsExplain GeV spectral cutoff by scattering Ly radiation (Cerruti et al. 2013)

GeV Spectral Cutoff

(Telfer et al. 2002)

(Ackermann et al. 2013)

Electron distribution (Abdo et al. 2009) absorption (Poutanen & Stern 2011)Compton scattering model (Finke & Dermer 2011)

Epoch A: August 2008 low state (Abdo et al. 2009) Epoch B: November 2010 high state (Abdo et al. 2011; Wehrle et al. 2012)

Spectral Fits to 3C 454.3

Cerruti et al. (2013)

UHECRs from Radio-Loud AGNs

Standard one-zone synchrotron/SSC model

Hillas condition:

Parameters: B, , R

1. Extragalactic2. Adequate energy production

rate within GZK volume3. Sources within GZK radius4. UHECRs can escape from

acceleration region5. Mechanism to accelerate to

ultra-high energies

UHECR sources must satisfy:

Murase, Dermer, Takami, Migliori (2012)

HiRes Collaboration 2008

Auger Collaboration 2009

Gamma-ray and Cosmic-ray Induced TeV emissionfrom Jetted Sources

,e+

,e-

e+

e-p p

UHECR protons with energies ~1019 eV make ~1016 eV e that cascade in transit and Compton-scatter CMBR to TeV energies

~100 Mpc ~ Gpc

Essey, Kalashev, Kusenko, Beacom (2010, 2011)

Weakly variable cascade radiation

e+

e-

Electromagnetic Signatures of UHECRs

Photopair-induced cascade in IGM

Murase et al. 2012

Polisensky & Ricotti 2011

>10 GeV Sources Explained by Cascade Emission

Fermi-LAT analysis– Pass 7– > 10 GeV – Source class– ROI between 8 and 15 degrees– Use 2FGL source list to remove background sources

-ray induced cascades– /Compton cascade– Use Kneiske et al. (2004) for low and best-fit EBL– Assume no suppression from IGMF ( 10-15 G < BIGMF < 10-20 G)

– Intrinsic source spectrum F(E) E-s , 5.6 GeV < E < 100 TeV

UHECR-induced cascade– Bethe-Heitler pair production, photopair production, expansion– UHECR proton sources spectrum: F(Ep) ~ Ep

-2.6exp(- Ep /Ep,c), Ep,c =1019 eV

– Assume no suppression from IGMF (10-10 G < BIGMF for protons)

KUV 00311-1938 (z = 0.61)

Normalization imposed to fit > 10 GeV Fermi-LAT spectrum from cascade emission

2 > 100 GeV -rays within 0.2o

Takami, Murase, Dermer 2013

Predictions for CTA

KUV 00311-1938 (z = 0.61)– Detected by HESS at 5.1s with 52.5 hrs observation

(Stegmann 2012)– L > 3.5x 1046 erg/s

– LUHECR >1.1 x1047 erg/s

PG 1246+586 (z = 0.847)– Not yet detected by TeV instrument– L > 7.5x1046 erg/s

– LUHECR >2.0x1047 erg/s

Other sources detectable by 50 hour observations with CTA in the Neronov et al. (2012) list are Ton 116, B3 1307+433, 4C +55.17, and PKS 1958-179.

KUV 00311-1938 (z = 0.61)

PG 1246+586 (z = 0.847)

Pair Production and Photohadronic Opacity in 4C +21.35

Detection of 40-700 GeV rays x >> 0.1pc →←pcttcr min)10/()100/(06.0 var

2var

2

Inject ultra-relativistic leptons:

Ben

Ben

20

Make synchrotron -raysDermer, Murase, Takami (2012)

• Modeling– New equipartition technique for fitting blazar SEDs– Fits to 3C 279– Emission region at outer edge of BLR– Explain GeV cutoffs of 3C 454.3

• UHECRs:– Blazars are the likely source of UHECRs, as can be tested with CTA– UHECRs from blazars would explain

• extra high-energy spectral components• Stecker-Scully relation,• weakly variable BL Lac class• VHE -ray production in FSRQs

Dermer MARLAM 26 September 2013

Summary

• GeV spectral breaks in FSRQs, LSP/ISP blazars• Rapid variability• Two classes of BL Lac objects• VHE radiation from FSRQs• EBL/IGMF relationship

EBL Effects on Blazar Spectra

GeV-TeV Spectral Index Difference Stecker-Scully (2006, 2010) relation

Measurements of IGMF

(>~ 10-15 G for persistent jet;

>~10-18 G for jet active for observing period)

Dermer et al. 2011

Origin of hard component in deabsorbed BL Lac spectra?

Fermi Observations of 4C+21.35

PKS 1222+2163 = 4C+21.35, z =

0.432Fermi LAT observations • Major flares 2010 April and June• sub-day scale variability • hour-scale variability (Foschini et al. 2011)• F peak at 1 – 10 GeV

Fermi-LAT spectrum

22

GeV-TeV Connection

21 joint GeV-TeV sourcesAbdo et al. (2009)

46 Extragalactic Sources listed in the VHE skyWagner’s catalog

Neronov et al. (2012) source catalog of 13 candidates of VHE emission at z > 0.5

–EBL effects greater on more distant blazars– (Ec,z) = 1 at Ec ≈ 100 GeV/z for 0.03 < z < 3

Model the >10 GeV Fermi-LAT emission by cascade rays vs. cascades induced by UHECRs

Find minimum required jet powers and predictions for CTA

Neronov et al. 2012

Five Big Fermi/IACT Blazar Discoveries

GeV spectral breaks in FSRQs, LSP/ISP blazars Rapid variability VHE radiation from FSRQs Two classes of BL Lac objects EBL/IGMF relationships

LBAS, Abdo et al. 2009

Five Big Fermi/IACT Blazar Discoveries

GeV spectral breaks in FSRQs, LSP/ISP blazars Rapid variability VHE radiation from FSRQs Two classes of BL Lac objects EBL/IGMF relationship

Ackermann et al. 2010 Abdo et al. 2009

3C 454.3

Five Big Fermi/IACT Blazar Discoveries

GeV spectral breaks in FSRQs, LSP/ISP blazars Rapid variability Two classes of BL Lac objects VHE radiation from FSRQs EBL/IGMF relationships

Albert et al. 2007

2005 July 9

MAGIC observations of Mrk 501

Feb 2010 VERITAS OBS of MRK 421,

Five Big Fermi/IACT Blazar Discoveries

GeV spectral breaks in FSRQs, LSP/ISP blazars Rapid variability Two classes of BL Lac objects VHE radiation from FSRQs EBL/IGMF relationship

HESS obs. of PKS 2155-304

RS/c = 104M9 s

tvar ~ 5 min = 300 s(?) M << 108 M0

28 July 2006 flare

Aharonian et al. 2007

Five Big Fermi/IACT Blazar Discoveries

GeV spectral breaks in FSRQs, LSP/ISP blazars Rapid variability Two classes of BL Lac objects VHE radiation from FSRQs EBL/IGMF relationship

Ackermann et al. 2010

3C 454.3

29

MAGIC Observations of PKS 1222+2163 = 4C+21.35

z = 0.432, flare of 17 June 2010MAGIC observations• Emission over 30 minutes• Flaring on timescales of 10 minutes• L ~ 1047 erg/s (TeV energies)

• L ~ 1048 erg/s (GeV energies) Black hole mass: 1.5x108 Mo (Wang et al. 2004)

extreme

Aleksic et al. (2011)

MAGIC spectrum

MAGIC light curve

Fermi-LAT and MAGIC spectrum

Tanaka et al. (2011)

= 3.7

Five Big Fermi/IACT Blazar Discoveries

GeV spectral breaks in FSRQs, LSP/ISP blazars Rapid variability Two classes of BL Lac objects VHE radiation from FSRQs EBL/IGMF relationship

Mrk 421

Mrk 501

Abdo et al. 2011b

Abdo et al. 2011a

Variable class– Mrk 421, Mrk 501–PKS 2155-305– 0716+714, etc.–Extreme sources– tvar < RS/c

GeV spectral breaks in FSRQs, LSP/ISP blazars Rapid variability Two classes of BL Lac objects VHE radiation from FSRQs EBL/IGMF relationship

Mrk 421

Mrk 501

Abdo et al. 2011b

Abdo et al. 2011a

Mrk 421

Mrk 501

Abdo et al. 2011b

Abdo et al. 2011a

Mrk 421

Mrk 501

Abdo et al. 2011b

Abdo et al. 2011a

B =0.015G, ′ =12, R =1.3x10′ 17 cm

B =0.038G, ′ =21, R =5.2x10′ 16 cm

tv = 1 d

tv = 4 d

Five Big Fermi/IACT Blazar Discoveries

Variable class– Mrk 421, Mrk 501–PKS 2155-305–Extreme sources– tvar < RS/c– SSC Model fits time-averaged emission

TeV BL Lac Objects

Highly variable class– Extreme sources– tvar < RS/c– SSC Model fits– Large inferred factors

Weakly variable class–Weak Fermi LAT fluxes –GeV-TeV spectrum: EBL, IGMF

Mrk 421

Abdo et al. 2011b

Albert et al. 2007

1ES 0229+200 z = 0.141ES 0347-121 z = 0.1861ES 1101-232 z = 0.141ES 0548-322 z = 0.069RGB J0152+0.17 z = 0.08

Tavecchio et al. 2011

Compton-scattered CMBR from extended jet/lobe Böttcher et al. 2008

GeV spectral breaks in FSRQs, LSP/ISP blazars Rapid variability Two classes of BL Lac objects VHE radiation from FSRQs EBL/IGMF relationship

VHE rays from FSRQs

Senturk et al. 2013

And PKS 1510-089With HESS and MAGIC