Astrophysical Sources of Neutrinos and Expected Rates Chuck Dermer U.S. Naval Research Laboratory TeV Particle Astrophysics II Madison, Wisconsin August 28, 2006 Armen Atoyan U. de Montral Jeremy Holmes Florida Institute of Technology Truong Le NRL Nonthermal Neutrinos from Photohadronic Production Mcke et al SOPHIA code Two-Step Function Approximation Atoyan and Dermer 2003 (useful for energy-loss rate estimates) Decay lifetime 900 n seconds Neutron -decay Flavor Changing Threshold m 140 MeV - connection But without (buried sources) without (leptonic emissions) Nonthermal Neutrinos from Secondary Nuclear Production e.g., Kelner, Aharonian, and Bugayov (PRD, 2006) Dermer 1986 Photon Targets (high radiation energy density and either VHE photons or particles) vs. Particle Targets (high target particle density but relatively low nonthermal particle energies) Threshold E p m 140 MeV 1. Isobaric production near threshold 2. Scaling representation at high energies Rules out nuclear production in jet sources ( Atoyan & Dermer 2003) Implications of the Connection Best bet Sources detection probability Gaisser, Halzen, Stanev 1995 Dermer & Atoyan NJP 2006 km-scale telescope (IceCube) has best detection probability near 100 TeV Number of detected: 100 TeV Diffuse Rays and Point Sources of Rays as Candidate Sources Diffuse Sources of Rays 1.Diffuse Galactic Gamma Ray Background (Berezinsky et al. 1993) 2.Supernova Remnants 3.Clusters of Galaxies 4.Diffuse Extragalactic Gamma Ray Background Point Sources of Rays 1.EGRET point source catalog (~ 100 MeV 5 GeV) (all sky) 2.HESS point source catalog (> 300 GeV several TeV) 3.MILAGRO/all-sky water Cherenkov 4.VERITAS/MAGIC in Northern Hemisphere 5.GLAST: fall 2007 EGRET Detection Characteristics Spark Chamber (vs. Silicon Tracker in GLAST) Two-week detection threshold 15 ph(>100 MeV) cm -2 s -1 (Dermer & Dingus 2004) (high-latitude sources; background limited) Hard spectrum (photon index s < 2) Energy range: ~100 MeV 5 GeV Threshold energy flux: ergs cm -2 s -1 Two week observation: ~10 6 sec Threshold fluence: ergs cm -2 s -1 Therefore examine which EGRET sources are bright and have hard spectra Catalog of Established High Energy (> 100 MeV) Gamma-Ray Sources Microquasars GRBs June 11, 1991 Kanbach et al Flare Spectrum -ray spectrum fit by slow-decaying (~255 minutes) pion emission and fast-decaying (~25 minutes) electron bremsstrahlung Energy flux at 100 MeV: ~ ergs cm -2 s -1 Energy fluence at 100 MeV: ~ 2 ergs cm -2 But very soft spectrum s > 3 4 Solar -Ray Flares Measured Integral Flux: = 19 ph(>100 MeV) cm -2 s -1 (Sreekumar et al. 1992) resulting spectral shape consistent with that expected from cosmic ray interactions with matter Third EGRET catalog (Hartman et al. 1999) = 14.4( 4.7) ph(>100 MeV) cm -2 s -1 s = 2.2(0.2) F = 2.3 (E/100 MeV) -0.2 ergs cm -2 s -1 >> 2 yrs to detect neutrinos from the LMC Large Magellanic Cloud Brightest persistent -ray sources F MeV cm -2 s -1 GeV cm -2 s -1 ergs cm -2 s -1 Therefore require only >> 10 5 s ~ 1 day to reach F >> ergs cm -2 s -1 Butspectra drop off steeply above 1 10 GeV (pulsar), 100 MeV (nebula) Thompson 2001 Vela pulsar Pulsed component consistent with electromagnetic cascade radiation in polar cap or outer gap Nebular component consistent with synchrotron + SSC component from cold MHD wind de Jager et al Crab nebula Pulsars Microquasars: VHE -Ray Detection of LS 5039 Aharonian et al. (2005) Confirms ID of Paredes et al. (2000) Cui et al. (2005) Mean orbital separation d 2.5 cm (0.2 AU) Companion Mass 23 M o (Casares et al. 2005) HESS Detection of LS 5039 at 200 GeV 10 TeV Consistent with point source (< 50 ) Multiwavelength Spectrum of LS 5039 Aharonian et al. (2005) F flux = ergs cm -2 s -1 assumed to extrapolate to 100 TeV with s = 2 spectrum requires >>10 8 sec 3 years to reach fluence level of >> ergs cm -2 s -1 (assuming hadronic emission; cf. Dermer and Bttcher 2006 ) Generic problem for detecting sources with F flux > years required to detect with a km-scale telescope Berrington and Dermer (2005) Integral photon flux ph(>E cm -2 s -1 ) 3C 296 Radio Galaxies and Blazars 3C 279, z = L ~10 45 x (f/ ergs cm -2 s -1 ) ergs s -1 Mrk 421, z = Cygnus A L ~5x10 48 x (f/10 -9 ergs cm -2 s -1 ) ergs s -1 FR2/FSRQ FR1/BL Lac Possible photon targets for p + : Internal: synchrotron radiation (Mannheim & Biermann 1992, Mannheim 1993, etc.) requires a compact jet: n phot ( ) L syn / R jet 2 target disappears with jet expansion on: t ' ~ R' jet /c ~ t var /(1+z) External : accretion disk radiation (UV) (i) direct ADR: (Bednarek & Protheroe 1999) anisotropic, effective up to R < 100 R grav < 0.01 pc (ii) ADR scattered in the Broad-Line region (Atoyan & Dermer 2001) quasi-isotropic, up to R BLR ~ pc Impact of the external ADR component: available on yrs scale (independent of L) high p -rates & lower threshold energies: prot MeV/(1- cos ) Photo-hadronic jet models =7 (solid) =10 (dashed) =15 (dot-dashed) (red - without ADR) (for 1996 flare of 3C 279) (3C 279) solid- neutrons escaping from the blob, and dashed- neutrons escaping from BL region (ext. UV) dot-dashed- rays escaping external UV filed ( produced by neutrons outside the blob ) dotted- CRs injected during the flare, and 3dot-dashed- remaining in the blob at l = R BLR Total energetics in UHE particles ( for parameters of the Feb 96 flare) =10 : W CR (>1 PeV) = erg, W n / W CR = 3.3%, W /W CR = 4.4% =15 : W CR (>1 PeV) = erg, W n / W CR = 8.9 %, W /W CR = 0.9% Particle energies in the neutral beam E ~ 1PeV- 3 EeV, E n ~ 10PeV - 30 EeV Neutron & -ray energy spectra & beam power Powerful FSRQ blazars / FR -II Radio Galaxies N eutrons with E n > 100 PeV and rays with E > 1PeV take away ~ 5-10 % of the total W CR (E > eV=1 PeV) injected at R1 PeV) = erg, W n / W CR = , W /W CR = =25 : W CR (>1 PeV) = erg, W n / W CR = , W /W CR = Particle energies in the neutral beam E < 1 EeV, E n ~ 30PeV - 5 EeV neutrons with E n > 100 PeV and rays with E > 1PeV take away 1 PeV) 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 = for = 10 (solid) and N = 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 UHE neutrons & -rays: energy & momentum transport from AGN core UHE -ray pathlengths in CMBR: l ~ 10 kpc - 1Mpc for the predicted E~ eV neutron decay pathlength: l d ( n ) = 0 c n, ( 0 ~ 900 s) l d ~ 1 kpc - 1Mpc for the predicted E~ eV High redshift jets: photomeson processes on neutrons turn on a new interpretation for large-scale jets ? (!) ( ??? ) solid: z = 0 dashed: z = 0.5 d ~ 200 Mpc l jet ~ 1 Mpc (l proj = 240 kpc) L X (jet) = erg/s L X (h.spot) = erg/s x ~ 1.1, radio ~ 0.8 S (syn.lobes) ~ erg/cm 2 s Pictor A in X-rays and radio (Wilson et al, 2001 ApJ 547) Pictor A Fluence distribution of 2135 BATSE GRBs Fluence Distribution of GRBs McCullough (2001) Detection of neutrinos requires GRBs at fluence levels > 3x10 -4 ergs/cm 2 (2-5 GRBs per year at this level) unless GRBs are hadronically dominated 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 ergs cm -2 = 100 Evidence for Anomalous -ray Emission Components in GRBs Long (>90 min) -ray emission (Hurley et al. 1994) GRB Nonthermal processes Two components seen in two epochs MeV synchrotron and GeV/TeV SSC lower limit to the bulk Lorentz factor of the outflow How to explain the two components? Two components seen in two separate epochs How to explain the two components? 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 (Gonzlez et al. 2003) GRB Second Gamma-ray Component in GRBs: Other Evidence (Requires low-redshift GRB to avoid attenuation by diffuse IR background) Delayed high-energy -ray emission from superbowl burst Seven GRBs detected with EGRET either during prompt MeV burst emission or after MeV emission has decayed away (Dingus et al. 1998) Average spectrum of 4 GRBs detected over 200 s time interval from start of BATSE emission with photon index 1.95 ( 0.25) (> 30 MeV) Atkins et al Bromm & Schaefer 1999 OBrien et al. (2006) Swift Observations of Rapid X-Ray Temporal Decays Tagliaferri et al. (2005) Rates for eV Protons with Equipartition Parameters Standard blast wave model with external density = 1000 cm -3, z = 1 Within the available time, photopion losses and escape cause a discharge of the proton energy several hundred seconds after GRB Rapid blast wave deceleration from radiative discharge causes rapid X-ray declines Dermer 2006 Neutrinos from GRBs in the Collapsar Model (~2/yr) Nonthermal Baryon Loading Factor f b = 20 Dermer & Atoyan 2003 requires Large Baryon-Loading 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 > eV Injection rate density determined by GRB formation rate (= SFR?) GZK cutoff from photopion processes with CMBR Ankle formed by [air production effects (Berezinsky and Grigoreva 1988, Berezinsky, Gazizov, and Grigoreva 2005) 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 UHECR Spectra for Different SFRs Provides good fits to HiRes data with f CR Waiting for next data release of Auger f CR 50 GZK neutrinos from UHECRs produced by GRBs Assume GRBs inject power-law distribution with exponentional cutoff energy = eV with rate density different SFR histories Dermer & Holmes 2006 f CR = 50 AMANDA RICE Halzen & Hooper 2006 Summary - Connection -ray fluence (extrapolated to 100 TeV) > ergs cm -2 required for detection for optically thin sources Best bet for detectable neutrino point source with km-scale detector (IceCube): v from photohadronic processes Blazar AGNs (FSRQs, not BL Lacs) Surrounding target radiation field; 1 PeV neutrino GRBs Signatures of hadronic acceleration in GRBs Microquasars (?) probably too weak Best bet for detectable diffuse neutrino sources: GZK neutrinos from cosmological sources of UHECRs (GRBs) Cosmic-ray induced galactic diffuse emission Lots of room for surprises