Mid-Atlantic Radio-Loud AGN Meeting, 27 September 2013 , STScI Radio-Loud AGNs as the Sources of the Ultra-High Energy Cosmic Rays Chuck Dermer (NRL) Naval Research Laboratory, Washington, DC charles.dermer@nrl.navy.mil Recent work with Matteo Cerruti (CfA), Catherine Boisson (LUTH), Andreas Zech (LUTH), Benoît Lott (CEN Bordeaux), Hajime Takami (KEK), Kohta Murase (IAS) We argue in favor of the hypothesis that UHECRs are accelerated in the jets of blazars. This hypothesis explains a number of unusual observations, including extra gamma-ray spectral components; unusual weakly-variable TeV gamma-ray blazars, including 1ES 0229+200 and 1ES 0347-121; flattening of the Stecker-Scully relation between GeV-TeV spectral index and redshift; and VHE gamma-ray production in FSRQs. Joint CTA and Fermi analysis of VHE blazars like KUV 00311-1938 can discriminate between photon-induced and UHECR-induced cascades. The search for gamma-ray echoes in the intergalactic magnetic field with strength B(IGMF) supports studies showing that B(IGMF) > 1e-18 G. Mid-Atlantic Radio-Loud AGN Meeting, 27 September 2013 , STScI Charles Dermer

Five Major Fermi/IACT Blazar Discoveries Observer 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 q BLR clouds G Relativistically Collimated Plasma Jet Dusty Torus Five Major Fermi/IACT Blazar Discoveries W Accretion Disk 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 SMBH G Ambient Radiation Fields

Equipartition Blazar Modeling Use log-parabola function for electron distribution From observations of Lsyn, nsyn, and tvar, derive parameters for B, Doppler factor dD, gpk , r’b Use numerical model to adjust parameters to fit data, implying energy density of the external radiation field and (minimum) absolute jet power Constrain location of the g-ray emission site Explain GeV cutoff in FSRQs and LSP/ISP blazars 3-parameter model: amplitude K, curvature b, gp 3

Equipartition Relations Assume (3-parameter) log-parabola function for electron distribution Use observables and equipartition relations to derive G, B, gp , DR’b log-parabola width gives monoenergetic electron specrum Spectral Relation: What does equipartition mean? Equipartition Relation: 4

Solution to System of Equations Corrections for b ≠  Minimum jet power Dermer et al. (2012) 5

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)

Implications External-field energy densities Jet Model Normally t = 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

GeV Spectral Cutoff Code improvements Explain GeV spectral cutoff by scattering Ly a radiation (Cerruti et al. 2013) Code improvements Multi-line model Thermal spectrum for dust radiation (Ackermann et al. 2013) (Telfer et al. 2002) Electron distribution (Abdo et al. 2009) gg absorption (Poutanen & Stern 2011) Compton scattering model (Finke & Dermer 2011) 12

Spectral Fits to 3C 454.3 Cerruti et al. (2013) Epoch A: August 2008 low state (Abdo et al. 2009) Epoch B: November 2010 high state (Abdo et al. 2011; Wehrle et al. 2012) 13

UHECRs from Radio-Loud AGNs HiRes Collaboration 2008 Auger Collaboration 2009 UHECRs from Radio-Loud AGNs Standard one-zone synchrotron/SSC model Parameters: B, d, R Hillas condition: UHECR sources must satisfy: Extragalactic Adequate energy production rate within GZK volume Sources within GZK radius UHECRs can escape from acceleration region Mechanism to accelerate to ultra-high energies Murase, Dermer, Takami, Migliori (2012)

Gamma-ray and Cosmic-ray Induced TeV emission from Jetted Sources Weakly variable cascade radiation lgg g g n,e+ e+ p0, p p p g 2g n,e- e- ~100 Mpc ~ Gpc UHECR protons with energies ~1019 eV make ~1016 eV e that cascade in transit and Compton-scatter CMBR to TeV energies Essey, Kalashev, Kusenko, Beacom (2010, 2011)

Electromagnetic Signatures of UHECRs Photopair-induced cascade in IGM Polisensky & Ricotti 2011 Murase et al. 2012

>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 g-ray induced cascades gg/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(Eg) Eg-s , 5.6 GeV < Eg < 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) 2 > 100 GeV g-rays within 0.2o Takami, Murase, Dermer 2013 Normalization imposed to fit > 10 GeV Fermi-LAT spectrum from cascade emission 17

Predictions for CTA KUV 00311-1938 (z = 0.61) PG 1246+586 (z = 0.847) Detected by HESS at 5.1s with 52.5 hrs observation (Stegmann 2012) Lg > 3.5x 1046 erg/s LUHECR >1.1 x1047 erg/s PG 1246+586 (z = 0.847) Not yet detected by TeV instrument Lg > 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. PG 1246+586 (z = 0.847) 18

Pair Production and Photohadronic Opacity in 4C +21.35 Inject ultra-relativistic leptons: Dermer, Murase, Takami (2012) Make synchrotron g-rays Detection of 40-700 GeV g rays  x >> 0.1pc →←

Dermer MARLAM 26 September 2013 Summary 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 g-ray production in FSRQs Dermer MARLAM 26 September 2013

EBL Effects on Blazar Spectra GeV spectral breaks in FSRQs, LSP/ISP blazars Rapid variability Two classes of BL Lac objects VHE radiation from FSRQs EBL/IGMF relationship Dermer et al. 2011 GeV-TeV Spectral Index Difference DG Stecker-Scully (2006, 2010) relation Measurements of IGMF (>~ 10-15 G for persistent jet; >~10-18 G for jet active for observing period) Origin of hard component in deabsorbed BL Lac spectra? 21

Fermi Observations of 4C+21.35 PKS 1222+2163 = 4C+21.35, z = 0.432 Fermi-LAT spectrum Fermi LAT observations Major flares 2010 April and June sub-day scale variability hour-scale variability (Foschini et al. 2011) nFn peak at 1 – 10 GeV 22 22

GeV-TeV Connection 21 joint GeV-TeV sources Abdo et al. (2009) 46 Extragalactic Sources listed in the VHE sky Wagner’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 tgg(Ec,z) = 1 at Ec ≈ 100 GeV/z for 0.03 < z < 3 Model the >10 GeV Fermi-LAT emission by cascade g rays vs. cascades induced by UHECRs Find minimum required jet powers and predictions for CTA Neronov et al. 2012 23

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 24

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 3C 454.3 Abdo et al. 2009 Ackermann et al. 2010 25

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 MAGIC observations of Mrk 501 2005 July 9 Feb 2010 VERITAS OBS of MRK 421, Albert et al. 2007 26

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 27

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 28

MAGIC Observations of PKS 1222+2163 = 4C+21.35 z = 0.432, flare of 17 June 2010 MAGIC spectrum MAGIC observations Emission over 30 minutes Flaring on timescales of 10 minutes Lg ~ 1047 erg/s (TeV energies) Lg ~ 1048 erg/s (GeV energies) Black hole mass: 1.5x108 Mo (Wang et al. 2004)  extreme MAGIC light curve G = 3.7 Fermi-LAT and MAGIC spectrum Aleksic et al. (2011) Tanaka et al. (2011)

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 Abdo et al. 2011a Variable class Mrk 421, Mrk 501 PKS 2155-305 0716+714, etc. Extreme sources tvar < RS/c Mrk 501 Abdo et al. 2011b 30

Five Big Fermi/IACT Blazar Discoveries Mrk 421 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 421 tv = 4 d Abdo et al. 2011a B′=0.015G, d=12, R′=1.3x1017 cm Abdo et al. 2011a Abdo et al. 2011a Variable class Mrk 421, Mrk 501 PKS 2155-305 Extreme sources tvar < RS/c SSC Model fits time-averaged emission Mrk 501 B′=0.038G, d=21, R′=5.2x1016 cm Mrk 501 tv = 1 d Mrk 501 Abdo et al. 2011b Abdo et al. 2011b Abdo et al. 2011b 31

TeV BL Lac Objects Highly variable class Weakly variable class Extreme sources tvar < RS/c SSC Model fits Large inferred G factors Weakly variable class Weak Fermi LAT fluxes GeV-TeV spectrum: EBL, IGMF Mrk 421 Tavecchio et al. 2011 1ES 0229+200 z = 0.14 1ES 0347-121 z = 0.186 1ES 1101-232 z = 0.14 1ES 0548-322 z = 0.069 RGB J0152+0.17 z = 0.08 Abdo et al. 2011b Albert et al. 2007 Compton-scattered CMBR from extended jet/lobe Böttcher et al. 2008 32

GeV spectral breaks in FSRQs, LSP/ISP blazars Rapid variability VHE g rays from FSRQs GeV spectral breaks in FSRQs, LSP/ISP blazars Rapid variability Two classes of BL Lac objects VHE radiation from FSRQs EBL/IGMF relationship Senturk et al. 2013 And PKS 1510-089 With HESS and MAGIC 33