1. Gamma Ray Sources Chuck Dermer Naval Research Laboratory Washington, DC USA TAUP 2007, Sendai, Japan, September 2007 Ground-based Cherenkov: VERITAS HESS Cangaroo III MAGIC  MAGIC-2 Milagro Topics in Astroparticle and Underground Physics Space-based: EGRET  GLAST AGILE Ongoing revolution in our understanding of  -ray sources TeV astronomyGeV astronomy + multi-wavelength/ multi-messenger information (talk by W. Hoffman) focus on GeV and extragalactic sources

2. The Gamma-Ray Sky Diffuse/unresolved emissions (Quasi)-quiescent radiations Pulsing sources Flaring sources Bursting sources

3. EGRET Detector Spark Chamber Energy range: ~100 MeV – 5 GeV Pointing Instrument (psf ~ 5.7° at 100 MeV) Two week observation: ~10 6 sec Field-of-view: ~1/24 th of the Full Sky Two-week detection threshold 15  10 -8 ph(>100 MeV) cm -2 s -1 (high-latitude sources; background limited) F Threshold energy flux: 10 -10 ergs cm -2 s -1 Energetic Gamma Ray Experiment Telescope on the Compton Gamma Ray Observatory Flew 1991 -- 2000

4. GLAST Detector LAT Tracker Energy range: ~ 50 MeV – 100 GeV Scanning Instrument (psf ~ 3.5° at 100 MeV) Views whole sky every 3 hours Field-of-view: ~1/5 th of the Full Sky One year detection threshold 0.4  10 -8 ph(>100 MeV) cm -2 s -1 (high-latitude sources; background limited) F threshold energy flux: 3 10 -12 ergs cm -2 s -1 Gamma Ray Large Area Space Telescope Large Area Telescope + GLAST Burst Monitor Launch: February 2008 (talk by C. Cecchi)

5. EGRET (> 100 MeV) All-Sky Map Requires background cosmic-ray/gas model to find  -ray sources

6. Catalog of Established High Energy (> 100 MeV) Gamma-Ray Sources High mass binaries/microquasars GRBs (Hartman et al. 1999) (271 Sources, plus 5 GRBs) (66/27 hi/low confidenceAGNs) + Radio galaxy (Cen A)

7. Casandjian & Grenier ‘07 Revised EGRET Catalog Before: After: 107 3EG sources not confirmed –most Gould Belt sources 32 new sources from 9-year data GeV/TeV irradiated cloud "sources"

8.  -Ray Supernova Remnants No unambiguous identification of a SNR with EGRET SNR maps with HESS –RX J1713.7-3946 –Vela Jr –RCW 86 Cosmic Ray Origin Problem –  rays from Compton- scattered CMB –  rays from CR p + p,N   0 Detection of  0 bump with GLAST Aharonian et al. 2007

9. Detection of LMC with EGRET   = 19  10 -8 ph(>100 MeV) cm -2 s -1 (Sreekumar et al.1992) spectral shape consistent with that expected from cosmic ray interactions with matter Scale to local galaxies (SMC, Andromeda) Starburst Galaxies (M82, NGC 253;  3 Mpc) IR Luminous Galaxies (Arp 220;  72 Mpc) (Torres 2004) Normal, Starburst and IR Luminous Galaxies

10. Clusters of Galaxies F  few  10 -13 ergs cm -2 s -1 at 1 TeV Implies >> years required to detect with a km-scale telescope UHECRs and secondary  rays from clusters? (talk by S. Inoue) Berrington and Dermer (2005) Integral photon flux ph(>E cm -2 s -1 ) (Armengaud, Sigl, & Miniati 2006)

11. 3C 296 Radio Galaxies and Blazars 3C 279, z = 0.538 L ~10 45 x (f/10 -10 ergs cm -2 s -1 ) ergs s -1 Mrk 421, z = 0.031 Cygnus A L ~5x10 48 x (f/10 -9 ergs cm -2 s -1 ) ergs s -1 FR2/FSRQ FR1/BL Lac FR1/2 dividing line at radio power  10 42 ergs s -1 BL Lacs: optical emission line equivalent widths < 5 Å

12. Redshift Distribution of EGRET  -Ray Blazars

13. Standard Blazar Model Collimated ejection of relativistic plasma from supermassive black hole Relativistic motion accounts for lack of  attenuation; superluminal motion; super- Eddington luminosities High energy beamed  rays made in Compton or photo- hadronic processes FSRQs have intense external radiation field from broad line-region gas

14. Evolution from FSRQ to BL Lac Objects in terms of a reduction of fuel from surrounding gas and dust FSRQ BL Lac Sambruna et al. (1996); Fossati et al. (1998) Böttcher and Dermer (2000) Cavaliere and d’Elia (2000) Understanding the blazar main sequence Blazar Main Sequence: Supermassive Black Hole Growth and Evolution

15. Black Hole Jet Physics Variability and Black Hole Mass Energy Source: Accretion vs. Rotation Two Component Synchrotron/ Compton Leptonic Jet Model Location of  -ray Emission Region Accretion Disk    SMBH Relativistically Collimated Plasma Outlfows Observer BLR clouds Dusty Torus Ambient Radiation Fields  BL Lac vs. FSRQ Hadronic Jet Model

16. Leptonic Blazar Modeling z = 0.538 L ~5x10 48 x (f/10 14 Jy Hz) ergs s -1 Temporally evolving SEDs Evolution of electron distribution with time: information about acceleration (e.g., loop diagrams); Correlated behavior expected for leptonic emissions Infer B field, Doppler power, jet power, location Böttcher et al. 2007

17. Infer intrinsic spectrum with EBL absorption Implied large Doppler factors of TeV blazars Orphan TeV flares Linear jets Aharonian et al., Nature, 2005 Evidence for Anomalous  -Ray Components in Blazars z = 0.186

18. d ~ 200 Mpc l jet ~ 1 Mpc (l proj = 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 ApJ 547) Pictor A

19. Sreekumar et al. (1998) Blazars as High Energy Hadron Accelerators astro-ph/0610195 Synchrotron and IC fluxes from the pair-photon cascade for the Feb 1996 flare of 3C279 (3C 279) dotted - CRs injected during the flare; solid - neutrons escaping from the blob, dashed - neutrons escaping from Broad Line Region (ext. UV) dot-dashed -  rays escaping external UV field ( produced by neutrons outside the blob ) 3dot-dashed- Protons remaining in the blob at l = R BLR Powerful blazars / FR -II Neutrons with E n > 100 PeV and  rays with E  > 1PeV take away ~ 5-10 % of the total W CR (E > 10 15 eV=1 PeV) injected at R<R BLR

20. UHE neutrons &  -rays: energy & momentum transport from AGN core UHE  -ray pathlengths in CMBR: l  ~ 10 kpc - 1Mpc for the E n ~ 10 16 - 10 19 eV Neutron decay pathlength: l d (  n ) =  0 c  n, (  0 ~ 900 s)  l d ~ 1 kpc - 1Mpc for the predicted E~ 10 17 - 10 20 eV High redshift jets: photomeson processes on neutrons turn on solid: z = 0 dashed: z = 0.5 Detection of single high-energy from blazars  neutral beams could power large-scale jets

21. Neutrinos: expected fluences/numbers Expected  - fluences calculated for 2 flares, in 3C 279 and Mkn 501, assuming proton aceleration rate Q prot (acc) = L rad (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. N.B. : all neutrinos are expected at E>> 10 TeV

22. GRBs Multiple Classes 1. Long duration GRBs 2. X-ray flashes 3. Low-luminosity GRBs 4. Short Hard Class of GRBs Long Duration GRBs Massive Star Origin Collapse to Newly Formed Black Hole Prompt phase: internal or external relativistic shocks Afterglow phase: external shock Mean redshift: ~1 (BATSE), ~2 (Swift)GRB/Supernova connection Kouveliotou et al. 1993

24. Anomalous  -ray Emission Components in GRBs Long (>90 min)  -ray emission (Hurley et al. 1994)

25. Anomalous High-Energy Emission Components in GRBs Evidence for Second Component from BATSE/TASC Analysis Hard (-1 photon spectral index) spectrum during delayed phase − 18 s – 14 s 14 s – 47 s 47 s – 80 s 80 s – 113 s 113 s – 211 s 100 MeV 1 MeV (González et al. 2003) GRB 941017

26. Second Gamma-ray Component in GRBs: Other Evidence Delayed  -ray emission from superbowl burst GRB 930131 Low significance Milagrito detection of GRB 970417A (Requires low-redshift GRB to avoid attenuation by diffuse IR background) Atkins et al. 2002Sommer et al. 1994

27. Photon and Neutrino Fluence during Prompt Phase Hard  -ray emission component from hadronic-induced electromagnetic cascade radiation inside GRB blast wave Second component from outflowing high-energy neutral beam of neutrons,  - rays, and neutrinos Nonthermal Baryon Loading Factor f b = 1  tot = 3  10 -4 ergs cm -2  = 100

28. Gamma-Ray Bursts as Sources of High-Energy Cosmic Rays Solution to Problem of the Origin of Ultra-High Energy Cosmic Rays (Wick, Dermer, and Atoyan 2004) (Waxman 1995, Vietri 1995, Dermer 2002) Hypothesis requires that GRBs can accelerate cosmic rays to energies > 10 20 eV Injection rate density determined by GRB formation rate (= SFR?) GZK cutoff from photopion processes with CMBR Ankle formed by pair production effects (Berezinsky and Grigoreva 1988, Berezinsky, Gazizov, and Grigoreva 2005)

29. Star Formation Rate: Astronomy Input Hopkins & Beacom 2006 USFR LSFR HB06 SFR6, pre-Swift Le & Dermer 2006 SFR6, Swift SFR6, pre-Swift Fitting Redshift and Opening-Angle Distribution

30. Cosmogenic GZK  -Ray Intensity (Le & Dermer 2006) Dermer, unpublished calculations, 2007 astro-ph/0611191

31. Neutrinos from GRBs in the Collapsar Model (~2/yr) Nonthermal Baryon Loading Factor f b = 20 Dermer & Atoyan 2003 requires Large Baryon-Loading (diffuse background from GRBs: talk by K. Murase)

32. Sreekumar et al. (1998) Unresolved  -Ray Background Strong, Moskalenko, & Reimer (2000) Data: Star-forming galaxies (Pavlidou & Fields 2002) Starburst galaxies (Thompson et al. 2006) Pulsar contribution near 1 GeV Galaxy cluster shocks ( Keshet et al. 2003, Blasi Gabici & Brunetti 2007) Dark matter contribution ( talk by Bergstrom) BL Lacs: ~2 - 4% (at 1 GeV) FSRQs: ~ 10 - 15% astro-ph/0610195

33. GeV  -ray Astronomy: Some Important Problems Particle acceleration theory Origin of galactic cosmic rays Jet physics, differences between radio/  -ray black hole sources Blazar demographics Search for hadronic emission components: Acceleration of UHECRs in extragalactic sources (predictions for astronomy) Origin of diffuse/unresolved  -ray background Summary Waiting for GLAST…