UHECRs from Black-Hole Jet Sources Chuck Dermer Space Science Division US Naval Research Laboratory, Washington, DC charles.dermer@nrl.navy.mil "Searching for the Origins of Cosmic Rays" Trondheim, Norway, June 15-18, 2009 Happy Birthday, Venya!

Black-Hole Jet Sources of UHECRs Nonthermal g rays  relativistic particles + intense photon fields Leptonic jet model: radio/optical/ X-rays: nonthermal lepton synchrotron radiation Hadronic jet model: Photomeson production second g-ray component pg → p → g, n, n Neutrons escape to decay and become UHECR protons (Neutral beam model: Atoyan & Dermer 2003) Large Doppler factors required for g-rays to escape Photohadronic vs. ion synchrotron models

Outline Requirements for UHECR sources: Extragalactic (but within the GZK radius) Emissivity (>1044 erg Mpc-3 yr-1) Power (> 1046 erg s-1) (for Fermi acceleration) Extragalactic Gamma Ray Sources from Fermi Radio Galaxies and Blazars as Sources of the UHECRs Gamma-Ray Bursts as Sources of the UHECRs Dermer, Razzaque, Finke, Atoyan (New Journal of Physics, 2009) Razzaque, Dermer, Finke (Nature Physics, submitted, 2009) Dermer and Menon, “High Energy Radiation from Black Holes: Gamma Rays, Cosmic Rays, and Neutrinos” (Princeton University Press, 2009)

GZK Horizon Distance for Protons Horizon distance vs. MFP: Linear distance where proton with measured energy E had energy eE CMBR only: Auger limits: Auger finds that sources of UHECRs with energies > 60 EeV come from d < 75 Mpc Correlsation with sources require that deflection in IGM field < 0.1 rad GZK cutoff consistent with UHECR protons For model-dependent definition: Harari, Mollerach, and Roulet 2006

UHECR Emissivity knee ankle

UHECR Emissivity Yamamoto et al. (2007) 1020 0.4 1019 0.8 1018 3 1017 40 Sources of UHECRs need to have a local luminosity density (emissivity) of 1044 erg/Mpc3-yr

UHECR Acceleration by Relativistic Jets Proper frame (´) energy density of relativistic wind with apparent luminosity L x Maximum particle energy G Lorentz contraction  DR´= G DR R´= R/ G What extragalactic sources have (apparent isotropic) L >> 1046 ergs s-1? Those with (apparent isotropic) Lg > 1046 ergs s-1

Fermi Bright Sources (3 month source list) Subset of LAT Bright Source List, 0FGL (Fermi Gamma-ray LAT): Abdo et al. arXiv:0902.1340 (ApJ, in press) LAT Bright AGN Sample (LBAS): Abdo et al. arXiv:0902.1559 (ApJ, in press) 0FGL: 205 LAT Bright Sources Test Statistic > 100 Significance > 10s 132 |b|>10 sources 114 associated with AGNs Compare EGRET: 31 >10s sources (total) (10 at |b|>10) August 4 – October 30, 2008

UHECRs from Radio Galaxies and Blazars Cygnus A FRII/FSRQ L ~1045 x (f/10-10 ergs cm-2 s-1) ergs s-1 Mrk 421, z = 0.031 Fanaroff-Riley Classification: Morphology correlates with radio power at 2x1025 W/Hz at 178 MHz ( 4x1040 ergs s-1), or total radio power of 1042 ergs s-1 Optical emission lines in FR IIs brighter by an order of magnitude than in FR Is for same galaxy host brightness FRI/BL Lac 3C 279, z = 0.538 FRI/II dividing line at radio power 1042 ergs s-1 L ~5x1048 x (f/10-9 ergs cm-2 s-1) ergs s-1 3C 296 BL Lacs: optical emission line equivalent widths < 5 Å

Luminosity Density of Blazars Minimum luminosity density of Radio Galaxies from LBAS 1044 ergs Mpc-3 yr-1

Cen A power: Bolometric radio luminosity: 4×1042 erg s-1 Centaurus A ~100 kpc × 500 kpc lobes 5e41 ergs/s in LBAS Gamma = 2.8 Need > 1046 erg s-1 apparent power to accelerate UHECR protons by Fermi processes Cen A power: Bolometric radio luminosity: 4×1042 erg s-1 Gamma-ray power (from Fermi): 5×1041 erg s-1 Hard X-ray/soft g-ray power: 5×1042 erg s-1 UHECR power: few ×1040 erg s-1

What is Average Absolute Jet Power of Cen A? Total energy and lifetime: Cocoon dynamics (Begelman and Cioffi 1989 for Cyg A) Use synchrotron theory to determine minimum energy B field, absolute jet power Pj. Jet/counter-jet asymmetry gives outflow speed: Hardcastle et al. 2009

Mean B-field and Average Absolute Jet Power in Cen A Hardcastle et al. 2009 Pj(Cen A)  1044 erg s-1 Apparent jet power 100 x larger?

Search for UHECRs Enhancements from Radio Galaxies and Blazars Blue: Auger, > 56 EeV (1◦) Red: HiRes > 56 EeV (1◦) Magenta: AGASA, > 56 EeV (1.8◦) Orange: AGASA, 40-56 EeV (1.8◦) Pink and purple circles: angular deflections of UHECRs with 40 EeV and 20 EeV from source AGN, respectively, in the galactic disk magnetic field. Green circles represent angular deflections in assumed 0.1 nG intergalactic magnetic field, assuming no magnetic-field reversals. GC GC Hammer-Aitoff projection in galactic coordinates of UHECR arrival directions and directions to nearby prominent AGN; the direction to the Galactic Center is at the left and right extremities of this plot. Thick blue, red, and orange and magenta circles correspond to UHECRs with > 56 EeV from Auger, > 56 EeV from HiRes, and > 40 EeV from AGASA, respectively. The radii of the circles reflect the angular errors in the reconstructed cosmic ray directions, which is 1◦ for both Auger and HiRes and 1.8◦ for AGASA. The centers of the concentric green, purple and pink circles correspond to the named AGN directions. The pink and purple circles represent angular deflections from the source AGN of the arriving cosmic rays with 40 EeV and 20 EeV energies, respectively, in the µG galactic disk magnetic field, using eq. (2). The green circles, on the other hand, represents angular deflection in an assumed 0.1 nG intergalactic magnetic field, assuming no magnetic-field reversals. The dashed and dot-dashed curves correspond to the equatorial and super-galactic planes. z

UHECRs from Gamma Ray Bursts GRB: Burst of g rays accompanying black-hole formation Classes of GRBs Long duration GRBs (collapse of massive stellar core) Short hard class of GRBs (coalescence of compact objects) Low luminosity GRBs All-sky g ray map in Galactic coordinates (Galactic coordinates) Long Duration GRBs Found in Star Forming Galaxies GRB/Supernova connection Collapse to Newly Formed Black Hole Prompt phase: internal or external relativistic shocks Afterglow phase: external shock Mean redshift: ~1 (BATSE), ~2 (Swift) g-ray Light Curve of GRB Swift mission discovered that short hard class of GRBs are related to old stellar populations (Gehrels et al. 2005)

GRB X-ray/g-ray Emissivity GRB fluence: > 20 keV fluence distribution of 1,973 BATSE GRBs (477 short GRBs and 1,496 long GRBs). 670 BATSE GRBs/yr (full sky) Vietri 1995; Waxman 1995 (independent of beaming) Baryon loading (Band 2001)

Ultra-high Energy Cosmic Rays from Gamma Ray Bursts Inject -2.2 spectrum of UHECR protons to E > 1020 eV Injection rate density determined by birth rate of GRBs early in the history of the universe High-energy (GZK) cutoff from photopion interactions with cosmic microwave radiation photons Ankle formed by pair production effects (Berezinsky and colleagues) Wick, Dermer, and Atoyan 2004 Test UHECR origin hypothesis by detailed fits to measured cosmic-ray spectrum

Effects of Different Star Formation Rates g-ray signatures of UHECRs at source can confirm this hypothesis Hopkins & Beacom 2006

Fermi LAT GRBs as of 090510 192 GBM GRBs ~30 short GRBs 8 LAT GRBs

Light Curves of GRBs 080825C, 081024B First LAT GRB. Note: Preliminary First LAT GRB. Note: delayed onset of high-energy emission extended (“long-lived”) high-energy g rays First short GRB with >1 GeV photon detected

GRB 080916C: Luminous Fermi GRB ±30 deg region around GRB 080916C GRB at 48˚ from the LAT boresight at T0‏ RGB= <100 MeV, 100 MeV - 1 GeV, >1 GeV Before the burst (T0-100 s to T0)‏ During the burst (T0 to T0+100 s)‏ Black region = out of FoV

GRB 080916C: Notable Firsts Largest number, ~145, of >100 MeV photons from a GRB  Allows time-resolved spectral studies First high-energy 100 MeV – GeV detection of a GRB with known redshift z = 4.35±0.2 from GROND photometry on 2.2 m in La Silla, Chile (Greiner et al. 2009) Large fluence burst (2.4×10-4 ergs s-1) at 10 keV – 10 GeV energies  Apparent isotropic energy release 8.8×1054 erg  Supports the black-hole jet paradigm of GRB Highest energy photon, E = 13.22+0.70-1.54 GeV from a GRB with measured redshift  Constraints on the jet Doppler factor/bulk Lorentz factor, emission region  Implications for Extragalactic Background Light (EBL) models  Limit on Quantum Gravity mass scale Significant  4s delay between onset of >100 MeV and 100 keV radiation  Implications for high-energy spectral modeling, leptonic/hadronic origin Results published in Science (Abdo et al., vol. 323, issue 5922, page 1668, 2009)

Light Curves of GRB 080916C Again, two notable features: 8 keV – 260 keV 260 keV – 5 MeV LAT raw LAT > 100 MeV LAT > 1 GeV T0 Again, two notable features: Delayed onset of high-energy emission Extended (“long-lived”) high-energy g rays seen in both long duration and short hard GRBs

Interpretation of Delayed Onset of >100 MeV Emission Random collisions between plasma shells  Separate emission regions from forward/reverse shock systems  Second pair of colliding shells produce, by chance, a harder spectrum  Expect no time delays for >100 MeV in some GRBs, yet to be detected Opacity effects  Expansion of compact cloud, becoming optically thin to >100 MeV photons  Expect spectral softening break evolve to higher energy in time, not observed GRB 080916C Up-scattered cocoon emission Synchrotron-self-Compton for < MeV External Compton of cocoon photons, arriving late from high-latitude, to >100 MeV Toma, Wu, Meszaros (2009) Proton synchrotron radiation Inherent delay to build-up proton synchrotron flux which sweeps into LAT energy range from high-energy end Razzaque, Dermer and Finke (2009)

Synchotron Radiation from UHE Protons Instantaneous energy flux F (erg cm-2 s-1); variability time tv, redshift z Implies a jet magnetic field rb is baryon loading-parameter (particle vs. g-ray energy density) xB gives relative energy density in magnetic field vs. particles G > Gmin  103G3 from gg opacity arguments Fluence (50-300): 3.4x10^-7 ergs.cm-2

Fermi Acceleration of Protons in GRB Blast Waves Protons gain energy on timescales exceeding Larmor timescale, implying acceleration rate f is acceleration efficiency Saturation Lorentz factor: Proton saturation frequency (in mec2 units): Observer measures a time for protons to reach Fluence (50-300): 3.4x10^-7 ergs.cm-2

Time for Proton Synchrotron Radiation to Brighten gg processes induce second generation electron synchotron spectrum at i.e., ~ 500 MeV for standard parameters Time for proton synchrotron radiation to reach esat,e: Fluence (50-300): 3.4x10^-7 ergs.cm-2

Long GRBs as the Sources of UHECRs Maximum energy of escaping protons Long GRB rate 2fb Gpc-3 yr-1 at the typical redshift z  1–2 10 smaller at 100d100 Mpc due to the star formation fb > 200 larger due to a beaming factor 60E60 EeV UHECR deflected by an angle IGM field with mean strength BnGnG coherence length of l1 Mpc Number of GRB sources within 100 Mpc with jets pointing within 4 of our line-of-sight is  If typical long duration GRBs have a narrow core accelerating UHECRs, then GRBs could account for Auger events within GZK radius.

Extended High Energy Emission GRB 080916C All LAT detected GRBs show significant high energy emission extending after the low energy emission has (almost) disappeared below detectability (discovered originally with EGRET on Compton Observatory; Hurley et al. 1994) GRB080916C shows HE emission that extends more than 1000 sec. beyond the detectable keV-MeV emission Could be due to … Delayed arrival of Compton-scattered synchrotron photons (SSC) Though no hard spectrum observed as expected from SSC, unknown reason for delay Emission from >TeV -ray induced cascade in CMB (e.g., Razzaque, Meszaros & Zhang 2004) Requires very small (<10-16 G) intergalactic magnetic field Long-lived hadronic emissions (Böttcher and Dermer 1998) Abdo et al., Science, 323, 1668 (2009)

Ruled out: Viable: UHECRs accelerated by black-hole jets UHECR Origin Ruled out: Galactic sources young neutron stars or pulsars, black holes, GRBs in the Galaxy Particle physics sources superheavy dark matter particles in galactic halo top-down models, topological defects Clusters of galaxies Viable: Jets of AGNs: radio-loud or radio-quiet? Cen A!, M87? GRBs: Magnetars? Others? Requires nano-Gauss intergalactic magnetic field UHECRs accelerated by black-hole jets

Neutral Beam Model for UHECRs in Blazars Possible photon targets for p +: Internal: synchrotron radiation External: accretion disk radiation (UV) (i) direct accretion disk radiation: (ii) accretion disk radiation scattered in the broad-line region (Atoyan & Dermer 2001) quasi-isotropic, up to RBLR~ 0.1-1 pc Impact of the external accretion-disk radiation component: high p-rates & lower threshold energies: =7 (solid) =10 (dashed) =15 (dot-dashed) (red - without ADR) (for 1996 flare of 3C 279)

Blazars as High Energy Hadron Accelerators Powerful blazars / FR-II Neutrons with En > 100 PeV and rays with E > 1 PeV take away ~ 5-10 % of the total energy injected at R<RBLR (3C 279) Synchrotron and IC fluxes from the pair-photon cascade for the Feb 1996 flare of 3C279 dotted - CRs injected during the flare; solid - neutrons escaping from the blob, dashed - neutrons escaping from Broad Line Region (ext. UV) dot-dashed - g rays escaping external UV field (from neutrons outside the blob) 3dot-dashed- Protons remaining in the blob at l = RBLR astro-ph/0610195 Sreekumar et al. (1998)

Hadronic g-Ray Emission from Blazars Gamma rays from hadron-induced cascades: Orphan g-ray flares

Neutrinos: Predicted Fluences/Numbers Expected  - fluences calculated for 2 flares, in 3C 279 and Mkn 501, assuming proton aceleration rate Qprot(acc) = Lrad(obs) ; red curves - contribution due to internal photons, green curves - external component (Atoyan & Dermer 2003) Expected numbers of  for IceCube-scale detectors, per flare: 3C 279: N = 0.35 for  = 6 (solid curve) and N = 0.18 for  = 6 (dashed) Mkn501: N = 1.2 10-5 for  = 10 (solid) and N = 10-5 for  = 25 (dashed) (`persistent')  -level of 3C279 ~ 0.1 F (flare) , ( + external UV for p )  N ~ few - several per year can be expected from poweful HE  FSRQ blazars.

energy and momentum transport from AGN core UHE neutrons and  rays energy and momentum transport from AGN core UHE -ray pathlengths in CMBR: l ~ 10 kpc - 1Mpc for En ~ 1016 - 1019 eV Neutron decay pathlength: ld (n) = 0 c n (0 ~ 900 s)  ld ~ 1 kpc – 1 Mpc for E ~ 1017 - 1020 eV solid: z = 0 dashed: z = 0.5

Pictor A l jet ~ 1 Mpc (lproj = 240 kpc) Deposition of energy through d ~ 200 Mpc l jet ~ 1 Mpc (lproj = 240 kpc) Deposition of energy through ultra-high energy neutral beams (Atoyan and Dermer 2003) Pictor A in X-rays and radio (Wilson et al, 2001)

Hadronic GRB Modeling in Collapsar Scenario Nonthermal Baryon Loading Factor fb = 30 Energy injected in protons normalized to GRB synchrotron fluence Injected proton distribution Cooled proton distribution Forms neutral beam of neutrons, g rays, and neutrinos Escaping neutron distribution

Photon and Neutrino Fluence during Prompt Phase Nonthermal Baryon Loading Factor fb = 1 Ftot = 310-4 ergs cm-2 dD = 100 Hard g-ray emission component from hadronic-induced electromagnetic cascade radiation inside GRB blast wave Second component from outflowing high-energy neutral beam of neutrons, g-rays, and neutrinos