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UHECRs & GRBs Eli Waxman Weizmann Institute, ISRAEL
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The acceleration challenge R B v v 2R t RF =R/ c) l =R/ 22 22 [Hillas, ARA&A (1984); Waxman 04]
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The suspects Active Galactic Nuclei (steady): ~ few requires L>10 47 erg/s Few, brightest AGN Gamma Ray Bursts (transient): ~ 300 requires L>10 51 erg/s Average L ~10 52 erg/s
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The Suspects losses 1/ [Hillas 84; Arisaka 02]
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Comments on “ Magnetars ” Newborn Neutron stars (Hypothesis) with: B~10 14 G, ~10 4 /sec L EM ~10 50 erg/s for t<1 min. Some difficulties: Wind should penetrate envelope with <10 -12 M sun entrainment Acceleration mechanism: Unknown NS ~1 M sun envelope EM wind [e.g. Blasi, Epstein, Olinto 00; Arons 02] [Waxman 04]
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Gamma-ray Bursts M on ~1 Solar Mass BH Relativistic Outflow e - acceleration in Collisionless shocks MeV ’s: L ~10 52 erg/s ~300 [Piran, Phys. Rep. 99; Meszaros, ARA&A 02; Waxman, Lec. Notes Phys. 598 (2003).] e - Synchrotron X-ray, UV Radio UHE p Acceleration
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Proton/electron acceleration: ‘ 95 Protons Acceleration/expansion: Synchrotron losses: Particle spectrum: p energy production: Electrons MeV ’ s: Optical depth: spectrum: energy production [Waxman 95, PRL 75, 386; ApJ 452, L1; Note: Constraints independent of details of acceleratiomn model (e.g. Gialis & Pelletier 04)]
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1997: BeppoSAX (GRB afterglows) Detection of (predicted) X-ray, Optical & Radio “ afterglow ” Identification of “ host ” galaxies, ~2 Detailed tests of the model Size measurements [scintillation, VLBI, sub-rel.] X-ray to radio (synchrotron) spectra [e.g. Meszaros, ARA&A 02] [Waxman, Kulkarni & Frail 98; Taylor, Frail, Berger & Kulkarni 04; Frail, Waxman & Kulkarni 00; Berger, Kulkarni & Frail04] [e.g. 970508, Wijers & Galama 98]
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Afterglow: UHECR implications L =10 51 erg/s -> L =10 52 erg/s Early optical afterglow: u B /u e ~1, ~10 2.5 Revised rates, energy 10/Gpc 3 yr -> 0.5/Gpc 3 yr E =10 52 erg -> E =10 53.5 erg [Zhang,Kobayashi, Meszaros 03; Soderberg, Ramirez-Ruiz 03] [Schmidt 01; Guetta, Piran, Waxman 03]
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Proton/electron acceleration Protons Acceleration/expansion: Synchrotron losses: Particle spectrum: p energy production: Electrons MeV ’ s: Optical depth: spectrum: energy production [Waxman 04] [Waxman 95] Afterglow 0.02 52
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UHECR generation Galactic heavy nuclei X-Galactic protons X-Galactic protons Generation spectrum & rate (z evolution follows SFR): <10 19 eV Galactic heavy nuclei Fly ’ s Eye fit: J G ~E -3.50 [Waxman 95; Bahcall & Waxman 03] [Watson 91, Nagano & Watson 00] ~10 19 eV
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Model vs. Data [Bahcall & Waxman 03] Ruled out at 5
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“ GZK sphere ” AGN, Radio-galaxies GRBs : For R GRB (z=0)~0.5/Gpc 3 yr Prediction: p D B [Waxman 95; Miralda-Escude & Waxman 96, Waxman 03]
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GRB Model Predictions >3x10 20 eV: Few, narrow spectrum sources; Fluctuations (no homogeneous GZK). Auger AGASA multiplets- statistical significance? [Miralda-Escude & Waxman 96] [Teshima 03; Finley & Westerhoff 04] [Watson 91, Cronin 93]
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“ Generic ” GRB ’ s Weak dependence on model parameters [Waxman & Bahcall 97, 99; Rachen & Meszaros 98; Alvarez- Muniz & F. Halzen 99; Guetta, Spada & Waxman 01; Guetta, Hooper, Alvarez-Muniz, Halzen & E. Reuveni 04]
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Summary GRBs >10 19 eV protons (acceleration, rate) Predictions 10 3 km 2 area detectors experiments: HiRes, Auger, T.A., EUSO/OWL GRBs 100TeV ’ s Flux 1Gton detectors Experiments: Baikal, AMANDA IceCube, Antares, Nestor, NEMO detection GRBs: CR puzzle, GRB progenitors & physics physics: appearance Lorentz Inv. (10 -16 ), Weak equivalence principle (10 -6 )
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Direct size measurement: Scintillation Finite size, cosmological source: h crit. ~few x 10 17 cm nene d d > Diffractive scintillation h [Frail, Waxman & Kulkarni 00]
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“ Cannon balls ” Proper motion: D&D 2003: >1.4 mas for 030329 Obs.: 0.1+-0.1 Inconsistent with scintillation suppression [ Dado, Dar & De Rujula 02]
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