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ANITA Meeting UC Irvine 23 November 2002 EHE Cosmic Rays, EHE Neutrinos and GeV- TeV Gamma rays David Kieda University of Utah Department of Physics.

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Presentation on theme: "ANITA Meeting UC Irvine 23 November 2002 EHE Cosmic Rays, EHE Neutrinos and GeV- TeV Gamma rays David Kieda University of Utah Department of Physics."— Presentation transcript:

1 ANITA Meeting UC Irvine 23 November 2002 EHE Cosmic Rays, EHE Neutrinos and GeV- TeV Gamma rays David Kieda University of Utah Department of Physics

2 David Kieda, Utah 24 November 2002ANITA Meeting UCI Outline 1)GZK energy Cosmic Ray Measurements 2)GZK energy Cosmic Ray Origin 3)EHE neutrino production 4)EHE neutrino fluxes 5)Conclusion

3 David Kieda, Utah 24 November 2002ANITA Meeting UCI UHE/EHE Cosmic Ray Astrophysics HiRes Fly’s Eye (2002)

4 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Astrophysics Fly’s Eye Detector (Dugway, Utah) Hires Fly’s Eye Detector (Dugway, Utah)

5 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Astrophysics 320 EeV Cosmic Ray: Energy beyond GZK cutoff (D. Bird et al Ap. J 441, 144 (1995)) GZK cutoff: (d>20 Mpc) Greisen PRL 16, 748 (1966) Zatsepin & Kuzmin JETP Lett 4, 78 (1966)

6 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Spectrum HiRes Fly’s Eye (2002)

7 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Spectrum AGASA Array (2002)

8 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Spectrum A simple energy rescale looks promising, But….. Aertures are energy dependent (especially for HiRes & Fly’s Eye) Bachall & Waxman (2002) Discrepancy due to differences energy scale factors (within quoted systematics)?

9 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Arrival Directions Cosmic Ray Akeno (2000). Clustering random chance probabilty ~1% In conflict with HiRes experiment (similar exposure) Hamburg 2001). Large Scale Anisotropy: Probe correlation with anisotropy of local Galactic population (SuperGalactic Plane) or Galactic Center, Galactic Plane. >AGN, starburst, magentar, GRB populations correlated with luminous mass >Dark Matter Halo: Annihilation, Z-burst of relic massive neutrinos Small Scale Anisotropy: Event clustering with < 10 degree separation. Point source searches. Competition between increasing particle rigidity and decreasing statistic>Narrow energy window?

10 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Sources Bottom-Up

11 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Propagation Effects 1) Quantum Gravity Lorentz violation eliminates GZK (Gonzales-Mestres 1999, 2000) *Reduced interaction cross section (smaller final product phase space) *Reduced Lorentz boosted energy of  CMB -> Probe with time delay of TeV Gamma rays from AGN 2) Z-Burst Models: High Energy Neutrino interacts with heavy relic neutrino in Galactic DM halo (But isn’t this just making thing worse?)

12 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Propagation Effects If CR are indeed extragalactic, and if GZK cutoff does exist, pion decay leads to guaranteed neutrino flux. Adapted from C. Spiering (2002).

13 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Sources Bottom-Up AGN with Pair production creating dip at 10 EeV V. Berezinsky et al (2002)

14 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Sources Bottom-Up Nearby Magnetars population (< 50 Mpc) with PetaGauss B fields yields dip Arons astro-ph/0208444

15 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Sources Top-Down Typical Topological defect fragmentation : Production of gammas, e+/e-, neutrinos with fluxes substantially greater than the cosmic rays (O. Kalashev et al 2002)

16 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Neutrinos Top-Down Models vs. Bottom up give strongly different predictions for Neutrino flux Absolute neutrino flux constrained by gamma/neutrino production ratio (GeV/TeV gamma measurements) Absolute neutrino flux constrained by absolute cosmic ray flux (Bachall & Waxman bound, Mannheim, Protheroe & Rachen bound) Some wiggle room if sources are opaque to gammas/cosmic rays and/or large distances to CR sources VERITAS, 2005 4 tel. 2007 7 tel. ANITA 2005 flight MAGIC, 1 tel., 2003 GLAST 2005 flight

17 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Neutrinos Production: Direct production in Top-Down Models (Topologcal defect decay, super-heavy dark matter annihilation, super-heavy X particle decay) Peak Energy ~100 EeV

18 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Neutrinos Production: Direct production in Top-Down Models Z-burst (Gelmaini, Cline, others) Peak Energy > 100 EeV

19 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Neutrinos Production: Secondary interactions of CR &  production/decay near acceleration region at EHE CR source (AGN, GRB) Peak energy ~ 10 PeV (Stecker and Salamon 1996)

20 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Cosmic Ray Background for Radio Cherenkov Measurements? Shock Wave

21 David Kieda, Utah 24 November 2002ANITA Meeting UCI EHE Neutrino Observations C. Spiering (2002). ANITA pushes EeV neutrino limits >Well below diffuse gamma/MPR bounds >Approaches W&B bond

22 David Kieda, Utah 24 November 2002ANITA Meeting UCI Conclusions Shock Wave Super GZK Cosmic rays Exist. Rate, energy spectrum, isotropy statistically limited Difficult to separate Top-Down vs. Bottom up models in cosmic ray properties TeV Gamma, BW & MPR bounds do not exclude a strongly peaked flux above 100 EeV. GZK+Universal EHE CR production yields predictable 10-100 EeV flux Absence of GZK production probably implies GQ Lorentz violation Confluence of next generation TeV gamma ray, high energy neutrino & high energy cosmic ray provide strong constraints. Radio observations by ANITA play a key role in the next 5-10 years.


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