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Neutrinos, AGN and Auger data

ANTARES Meeting December 5th, 2007. Neutrinos, AGN and Auger data. Nicolas Busca, APC. Scope. Auger found a correlation of CR with nearby AGN The UHECR flux at Earth is ~ 1 event/yr/1000km 2 Use this flux to normalize the 

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Neutrinos, AGN and Auger data

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  1. ANTARES Meeting December 5th, 2007 Neutrinos, AGN and Auger data Nicolas Busca, APC

  2. Scope • Auger found a correlation of CR with nearby AGN • The UHECR flux at Earth is ~ 1 event/yr/1000km2 • Use this flux to normalize the  • Will only consider interactions of CR with the AGN photon background • Results will refer to point source fluxes (diffuse flux study in progress…)

  3. Review of Auger results • Analysis: • Before May 26th 2006 - exploration • Found 12/15 events in correlation with a VC AGN by scanning for the best combination of angle, energy and redshift • (3.10, Emin = 56EeV, zmax=0.018) • Prescription • After May 26th 2006 - confirmation • Found 8/13 events in correlation with a VC AGN with parameters fixed a priori • Results: • After rescanning, the parameters were found to be  ~ 60, • Emin~60 EeV, zmax~0.024 (100 Mpc)

  4. Review of Auger results AGN correlation Super galactic plane • 21 events of E>57EeV (outside the galactic plane) • 19 within 3.20 of a VC AGN with z<0.018 (75 Mpc)

  5. Review of Auger results AGN correlation Virgo cluster Super galactic plane • 21 events of E>57EeV • 19 within 3.20 of a VC AGN with z<0.018 (75 Mpc)

  6. Review of Auger results AGN correlation 2 events (ESO 139 G12, 73 Mpc) Super galactic plane • 21 events of E>57EeV • 19 within 3.20 of a VC AGN with z<0.018 (75 Mpc)

  7. Review of Auger results AGN correlation 2 events (Cen A, 4 Mpc) Super galactic plane • 21 events of E>57EeV • 19 within 3.20 of a VC AGN with z<0.018 (75 Mpc)

  8. Review of Auger results • What does this mean? • CRs are anisotropic • CRs come preferentially from the direction of some VC AGN • But… • are AGN really the sources? • do CR sources have the same distribution as VC AGNs?

  9. Review of Auger results • What does this mean? • CRs are anisotropic • CRs come preferentially from the direction of some VC AGN • But… • are AGN really the sources? • do CR sources have the same distribution as VC AGNs? CRs traverse the environment of an AGN before reaching us!! (and produce neutrinos…)

  10. Implications for ’s • Production modes: • foreign (to the AGN) foreign CR nucleus • CRs are accelerated away from the nucleus • AGN need not be the source

  11. Implications for ’s • Production modes: • foreign (to the AGN) • local foreign local CR CR nucleus nucleus • CRs are accelerated away from the nucleus • AGN need not be the source • CRs are accelerated near the core of the AGN

  12. Implications for ’s • Production modes: • foreign (to the AGN) • local Interactions: + isospin symmetric interactions foreign local CR CR nucleus nucleus • CRs are accelerated away from the nucleus • AGN need not be the source • CRs are accelerated near the core of the AGN

  13. CR propagation in AGNs R R ~ 30 Rs ~ 6x1012 cm ~ 2x10-12 Mpc • Local: • CRs traverse exactly R • Foreign: • CR traverse Leff =  R •  is a free parameter

  14. AGN photon background Photon background (Cen A) Steinle (2006)

  15. AGN photon background

  16. Proton interaction length Cen A model Stecker (1991)

  17. Proton interaction length Cen A model Stecker (1991) thick thick

  18. Spectrum normalization • same exposure to both sources • same flux at Earth • but very different luminosity since DCenA ~ 4Mpc and DESO ~ 75 Mpc • ’s normalized together with the spectrum ESO 139 G12 Cen A

  19. Results: local mode • source optically thick above the photopion threshold • no UHECRs would be observed from the source • model is excluded

  20. Results: foreign mode,  = 1e-3

  21. Results: foreign mode,  = 6e-4

  22. Results: foreign mode,  = 3e-4

  23. Results: foreign mode,  = 1e-4

  24. Results: foreign mode,  = 1e-4 Evolution with spectral index ~ 10x each 0.2 (2.0 is 105 x less than 2.7)

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