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Astrophysical Accelerators of Ultra High Energy Cosmic Rays. → Kyoto U. Susumu Inoue (NAOJ). GRBs. AGNs. clusters. collaborators:. AGNs: H. Takami, T. Yamamoto, K. Sato. GRBs: K. Asano, P. Meszaros. clusters: G. Sigl, F. Miniati, E. Armengaud
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Astrophysical Accelerators ofUltra High Energy Cosmic Rays → Kyoto U. Susumu Inoue (NAOJ) GRBs AGNs clusters collaborators: AGNs: H. Takami, T. Yamamoto, K. Sato GRBs: K. Asano, P. Meszaros clusters: G. Sigl, F. Miniati, E. Armengaud F. Aharonian, N. Sugiyama, K. Murase, S. Nagataki +others
1. introduction with recent Auger results outline 2. AGNs: radio galaxies vs Auger and implications 3. GRBs: synchrotron g-rays from UHE nuclei 4. clusters: heavy nuclei as UHECRs UHE proton-induced X & g-rays contribution to sub-ankle CRs & neutrinos multi-messenger, multi-wavelength approach UHECR gamma-ray neutrino
EUHECR~ 3x1020 eV ~50J ~kinetic E of 100km/h fastball 160km/h tennis serve cosmic vs terrestrial accelerators ELHC~ 7TeV ~< kin. E of housefly (20mg, 7km/h) EKEKPS~ 12GeV ~ kin. E of mosquito (3mg, 5cm/s)
Auger anisotropy Science 318, 938 (2007) also arXiv:0712.2843 • 20/27 events >56 EeV correlated within <3.1 deg • with AGNs <75 Mpc (z<0.018) in Veron-Cetty AGN catalog • 2 events in direction of Cen A (nearest AGN) • 0 events from Virgo region
1. not isotropic! 2. sources are extragalactic, tracing large-scale structure on 100 Mpc (GZK horizon) scale -> Galactic ruled out 3. deflections in Galactic/extragalactic magnetic fields not severe at highest E -> birth of charged particle astronomy! Auger anisotropy: implications but otherwise sources still unknown e.g. heavy-dominant composition disfavored? depends on source+Galactic MF+extragalactic MF warning • still small statistics (~3 sigma)! • Veron-Cetty “catalog” highly nonuniform
Auger composition mixed composition at all E becoming heavier at highest E?? consistency with anisotropy? Watson arXiv:0801.2321
adapted from Yoshida & Dai 98 “Hillas plot” UHECR sources: acceleration E ≦ Ze B R (v/c) confinement B GRBs Emax acceleration vs: escape source lifetime adiab. expansion loss radiative loss B~∝R-1 AGN jets luminosity limit clusters B2/8p=eBL/4pR2G2bc -> L > (2cG2/beBe2)(E/Z)2 =1045.5 erg/s (G2/beB)(E/Zx1020eV)2 R Waxman 03
shock acceleration • - power-law spectrum • dN/dE~∝E-2 for strong shock • very efficient • typically ~10% of kinetic energy • consistent with observations • in-situ: interplanetary shocks, … • SNRs, radio galaxy hot spots, … upstream downstream shock front c.f. other acceleration mechanisms magnetic reconnection unipolar induction …
Inoue astro-ph/0701835 kinetic E input into the universe UHECR sources: energy budget AGNs (radio galaxies) z-dep. LF Willott+ 01 Lkin-Lrad correlation Rawlings 92 supernovae, GRBs ∝ star formation rate Porciani & Madau 01 ESN=1051 erg EGRB=1053 erg, indep. of beaming cluster accretion Press Schechter mass function Lacc(M)~0.9x1046 (M/1015 MQ)5/3 erg/s Keshet+ 04 UHECR budget @1019 eV differential (per unit z) uCR ~3x10-19 erg cm-3 ~1054 erg Mpc-3 dEkin/dz=(dt/dz)∫dL L dn/dL
GeV blazar FR 2 radio galaxy supermassive black hole +accretion disk (flow) active galactic nuclei (AGNs) high- power radio-loud (relativistic jet) ~<1% low- power ~9% radio- quiet (no jet) ~90% TeV blazar (BL Lac) FR 1 radio galaxy Seyfert galaxy radio-quiet quasar
near-nucleus R~1013-1014 cm B~104G? radio-quiet+radio-loud AGN AGNs: acceleration sites Emax~Epg~<1018eV e.g. Szabo & Protheroe 94 inconsistent with observed keV-MeV highest E not expected from Chandra webpage
near-nucleus low+high power (FR 1+2) radio galaxy AGNs: acceleration sites highest E not expected inner jet (blazar) R~1016-1017 cm B~0.1-1G Emax~Epg~<1020eV e.g. Mannheim 93 adiabatic loss -> n conversion escape? shear-layer acceleration? accel./escape nontrivial from Chandra webpage
near-nucleus high power (FR 2) radio galaxy AGNs: acceleration sites highest E not expected inner jet (blazar) Emax~Epg~<1020eV accel./escape nontrivial hot spot R~1021 cm B~1mG Emax~Eesc~1020-21eV e.g. Rachen & Biermann 93 accel./escape easiest from Chandra webpage but still nontrivial escape through cocoon +contact disc.?
Takami, SI, Yamamoto & Sato, in prep. high power (FR2) objects radio galaxies vs Auger radio galaxies (D<75Mpc): black Massaglia 07 1.4 GHz Auger: blue AGASA: green (>40 EeV) red (>20 EeV) no obvious correlations with bright FR2 or 1 radio galaxies! high+low power (FR2+1) objects Cen A statistical fluke? Wall & Peacock 85 2.7 GHz
may still be viable if: radio galaxies as UHECR sources 1. radio activity timescale < time delay during intergalactic propagation ~106-108 yr tdelay, uni(E, D)~107 yr (E20/Z)-2 D100Mpc2 lc,MpcB10nG2 2. acceleration in FR2 hot spots + escape after cessation of activity 3. acceleration in FR1 jets + escape during jet deceleration some combination of the above?
Takami, SI, Yamamoto & Sato, in prep. • real local large scale structure • <B> ∝ r2/3, norm. at cluster time delay in structured EGMF -> Takami’s talk 5<D<50Mpc D<5Mpc BVirgo=0.1mG 50<D<75Mpc E>1019.8 eV=63 EeV 75<D<100Mpc time delay (log yr)
Waxman 95 Vietri 95 GRBs: acceleration sites adapted from Meszaros 01 radio-IR-opt-X afterglow prompt X-g emission optical flash, radio flare internal shocks external reverse shock external forward shock R~G2ctvar~1012-1016 cm B~106-103 G Grel~1 R~Rdec~1016 cm B~10 G Grel~1 R~Rdec-RNR~1016-1018 cm B~10-0.01 G? >>BISM Grel>>1 escape nontrivial accel. nontrivial
Asano, SI & Meszaros, in prep. Vietri 97 synchrotron gamma-raysfrom UHE protons Ep~1020eV -> nsyn~GeV-TeV acceleration/survival of UHE nuclei in GRBs Wang+ arXiv:0711.2065 Murase+ arXiv:0801.2861 Inoue, in prep. synchrotron from UHE nuclei photon energy nsyn∝ E2 Z/A3 power Psyn∝ E2 Z4/A4 loss time tsyn∝ E-1 A4/Z4
Inoue, in prep. abundance at low E=Galactic CR source at fixed E/A H=1, He=0.07, C=3x10-3, O=3.7x10-3, Si= 7x10-4, Fe=7x10-4 nuclear synchrotron spectra (note: metals may be enhanced in GRBs!) normalize to proton synchrotron expansion limited case tacc(∝Z)=tdyn EZ∝Z, nZ∝Z3/A3, tZ∝A4/Z5 p EZ/Ep tZ/tp nfn He Fe x100 nZ/np C,O x10 C,O n Z proton dominant, but tsyn can be shorter!
tacc(∝Z)=tsyn(∝A4/Z4) synchrotron limited case nuclear synchrotron spectra EZ∝A/Z1.5, nZ∝A/Z2, tZ∝A2/Z2.5 p tZ/tp He nfn Fe x100 EZ/Ep nZ/np C,O C,O x10 n Z
tacc(∝Z)=tdis(∝~A1.2) photodisintegration limited case nuclear synchrotron spectra depends on low E spec. EZ∝Z/A1.2, nZ∝Z3/A5.4, tZ∝A5.2/Z5 p tZ/tp EZ/Ep nfn He nZ/np Z n
He observable -> crucial for interpretation of UHECR ankle nuclear synchrotron: implications C,O,Si,Fe… may be observable if H+He depleted (expected in GRB progenitors?) unique probe of UHE nuclei acceleration! He/p<0.05 required pair dip Gal.-extragal. transition Allard+ 07
accretion (minor merger) cluster accretion shocks Ryu+ 03 strong shocks accretion power Lacc(M)=fgasGMM/Rs ~1046 erg/s (M/1015 MQ)5/3 . Mach no. protons v~2000 km/s, Bs~1 mG -> Ep, max~ 1018-1019 eV Kang+ 97 HOWEVER Fe nuclei (Z=26) EFe, max>~1020 eV
SI, Sigl, Miniati & Armengaud, PRD (astro-ph/0701167) nuclei from cluster accretion shocks as UHECRs Emax acceleration vs CMB losses, lifetime shock radius, velocity, etc. Hubble Rs~3.2 Mpc Vs~2200 km/s Bs~ 1 mG (Bs,eq~ 6 mG) Bohm limit shock accel. time tacc=(20/3) rgc/Vs2 escape limit tesc~R2/5k(E) Emax/Z~7x1018 eV heavy nuclei Emax for Bs~1 mGEFe, max~1020 eV
spectrum consistent with some heavy enhancement nuclei from clusters as UHECRs spectrum composition confirmed by Xmax? anisotropy consistent depending on GMF+EMGF? with EGMF fCR~0.005-0.3 no EGMF fCR~0.002 anisotropy composition 100 events>4x1019eV 1000 events>4x1019eV heavier at higher E escape: diffusion away from filaments advection during merger disruption 1019 eV 1020 eV confirmed by Xmax?
solution to Virgo “hole”? Virgo? assume <Z>~10 heavy distortion by Galactic MF Centaurus Hydra A3627 Perseus 8x1014 MQ 78 Mpc Takami & Sato 07 proton deflection angle
p(1018eV) +gCMB→ p+ e+e- (1015eV) SI, Aharonian, Sugiyama 05 UHE proton-induced hard X+g emission from clusters e+e-+B(~mG)→keV, e+e-+gCMB→TeV Coma D=100 Mpc Suzaku NeXT, NuSTAR, SIMBOL-X HESS, MAGIC, CANG.3, VERITAS…
Murase, SI & Nagataki to be submitted sub-ankle energy CRs from clusters? probe through VHE neutrinos
Auger results summary extragalactic origin, but no unambiguous ID with sources AGNs (radio galaxies) little positional correlation with Auger events may still be viable depending on time delay and/or escape properties? GRBs probe of UHE nuclei acceleration through synchrotron GeV-TeV cluster accretion shocks heavy nuclei scenario: may be consistent with spectra, composition anisotropy too? probe through UHE proton-induced hard X-rays + TeV gamma-rays contribution to sub-ankle energies: probe through neutrinos other sources? starburst galaxies, merging galaxies, dormant black holes, extragalactic magnetars … UHECR sources still unknown! none of the above?
history of GRBs 180 bursts before 1991 Galactic NS! after 1991 NS-NS merger -> collapsar Woosley 93
30 events >60 EeV history of UHECRs? TA 2007 AGNs? 1000 events >60 EeV EUSO, AugerN+S… after 201x ??? ??? Inoue 201x???