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High Energy Neutrinos and Gamma-Ray Bursts

High Energy Neutrinos and Gamma-Ray Bursts. Kohta Murase (YITP) S. Nagataki, K. Ioka, T. Nakamura K. Asano, S. Inoue, H. Takami K. Sato, F. Iocco, P.D. Serpico. taken from IceCube homepage. Neutrinos as a Probe of Cosmic-Ray Acceleration.

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High Energy Neutrinos and Gamma-Ray Bursts

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  1. High Energy Neutrinos andGamma-Ray Bursts Kohta Murase (YITP) S. Nagataki, K. Ioka, T. Nakamura K. Asano, S. Inoue, H. Takami K. Sato, F. Iocco, P.D. Serpico

  2. taken from IceCube homepage Neutrinos as a Probe of Cosmic-Ray Acceleration Astrophysical Accelerators(GRB, AGN, Cluster of Galaxies…) → cosmic-rays accelerated above TeV even up to ZeV pp/ pγ → π , K　→ ν , γ pp/pγ reaction Neutrinos → good evidence of cosmic-ray acceleration (Especially useful as a probe of ~100 PeV energy cosmic-rays) Cosmic-rays → Deflection by magnetic fields (talk by Dr. Takami) Gamma-rays above TeV →Attenuation by CMB and CIB (talk by Dr. Asano) km3 telescopes (IceCube/KM3Net) Various model predictions have become testable • GRB (talk by Prof. Meszaros) • Merits! - time and position coincidence • Testing the shock model (baryonic or not?) • Magnetic field/amount of baryons • The origin of observed UHECRs?

  3. Plan of Talk Model-Predictions for High-Energy Neutrinos from Astrophysical Sources 1. Neutrino Emission & Gamma-Ray Bursts a. Pre-Swift Predictions (Prompt Emission) b. Swift-Era Predictions (Flares and so on) c. Neutrinos and Progenitors • Connection between Astrophysical Neutrino Sources and High-Energy Cosmic-Rays

  4. Gamma-Ray Bursts

  5. AfterglowsEp,max ~ ZeVEeV ν, GeV-TeV γ Meszaros (2001) Prompt Emission Ep,max ~ EeV-ZeV PeV ν, GeV-TeV γ Below Photosphere Ep,max ~ PeV-EeV TeV-PeV ν, invisible γ Flares/Early Afterglows Ep,max ~ EeV PeV-EeV ν, GeV γ

  6. Outline Prompt (Waxman & Bahcall 97), Afterglow (Waxman & Bahcall 00/Dermer 02) • Assumption that observed UHECRs come from GRBs (in original works) • Prediction of neutrinos associated with prompt and afterglow emission (And many studies, e.g., Halzen & Hooper 99, Guetta et al. 04, Asano 05) • Treatment of pγreaction: • Rectangular approx.→More sophistication • Inclusion of various cooling processes • Treatment of the GRB rate history: • GRB rate models→e.g. Guetta et al. (04,07) Δ-resonance KM & Nagataki, PRD, 73, 063002(2006) + Motivated by the recent Swift’s discoveries, we have predicted new possibilities of neutrinos and cosmic rays. KM & Nagataki, PRL, 97, 051101 (2006) KM, Ioka, Nagataki, & Nakamura, ApJL, 651, L5 (2006) KM, PRD, 76, 123001 (2007)

  7. AfterglowsExternal Shock ModelEeV ν, GeV-TeV γ (Waxman & Bahcall 00)(Dermer 02) Meszaros (2001) Prompt Emission from Classical (High-Luminosity) GRBs Internal Shock Model PeV ν, GeV-TeV γ (Waxman & Bahcall 97)

  8. Prompt Neutrino Emission z=1 A r~1013.5 cm B r~1014.5 cm Γ=300, Uγ=UB EGRB,γ=1053 ergs (A&B) r~1013-1015cm large uncertainties... • Inner range (~1013 cm) • neutrino efficient, UHECRs impossible • Middle range (~1014 cm) • neutrino efficient, UHE proton possible • Outer range (~1015 cm) • neutrino inefficient, UHE nuclei survive A: muon events ~ 0.1 B: muon events ~ 0.01 C: muon events ~ 1 (C is a very extreme case) Only nearby/energetic bursts can be promising (r-determination ← GLAST (e.g., KM & Ioka 08))

  9. The Cumulative Background Set A - r~1013-1014.5cm KM & Nagataki, PRD, 73, 063002(2006) Set B - r~1014-1015.5cm • ~10 events/yr by IceCube ( fiducial baryon load) • Our models are tested by AMANDA/IceCube group. The optimistic model is being constrained (Achterberg et al. 08) The key parameter – baryon loadingΕHECR ≡ε2 N(ε) Γ=102.5, Uγ=UB Current AMANDA limit higher baryon loading EHECR ~ 5 EGRB,γ fiducial baryon loading EHECR ~ EGRB,γ Towards testing the GRB-UHECR hypothesis through νs

  10. Early AfterglowsEeV ν, GeV-TeV γ (Dermer 07)(KM 07) Meszaros (2001) Prompt Emission from Low-Luminosity GRBs PeV ν, GeV-TeV γ (KM et al. 06) (Gupta & Zhang 06) Flares PeV-EeV ν, GeV γ (KM &Nagataki 06)

  11. Novel Results of Swift (XRF060218) • 1. Low-luminosity (LL) GRBs? • e.g., GRB060218 (XRF060218) • ・The 2nd nearby event (~140Mpc) • ・Associated with a SN Ic • ・Thermal component • (shock breakout?) • ・Much dimmer than usual GRBs • (ELL,γ ~ 1050 ergs ~ 0.001 EGRB,γ) • ・LL GRBs (e.g., XRF060218, GRB980425) • → more frequent than HL GRBs • (Local Rate ~ 102-3 Gpc-1 yr-3 ) • (Soderberg et al. 06, Liang et al. 07 • Guetta et al. 07 etc…) Rate Liang et al. (07) dark bright Luminosity

  12. Neutrinos from LL GRBs • Ex.) XRF060218-like burst • Prompt nonthrmal emission Epk ~ 5 keV • ↑Internal shock model (e.g., Toma, Ioka, Sakamoto, & Nakamura 07) • Prolonged thermal emission kT ~ 0.15 keV D=10Mpc Muon events ~ 1 event Muon events ~ 0.1 event r/Γ2=fixed See also Gupta & Zhang 07 For early afterglows see Yu, Dai, & Zheng (08) KM, Ioka, Nagataki, & Nakamura, ApJL, 651, L5 (2006)

  13. Novel Results of Swift (Flares) • 2. Flares in the early afterglow phase • Energetic (Eflare,γ ~ 0.1 EGRB,γ(Falcone et al. 07)) • (Eflare,γ ~ EGRB,γ for some flares such as GRB050502b) • δt >~ 102-3 s, δt/T < 1 → internal dissipation models • (e.g. late internal shock model) • Flaring in the (far-UV)/x-ray range (Epeak ~ (0.1-1) keV) • (Maybe) relatively lower Lorentz • factors (Γ ~ a few×10) • Flares are common • (at least 1/3 ~ 1/2 of LGRBs) • (even for SGRBs) • Baryonic (possibly dirty • fireball?) vs non-baryonic? • ↑neutrinos! Flares Burrows et al. (07)

  14. Energetics Photopion (p→π) Production Efficiency Nonthermal Baryon Energy Neutrino Energy Flux ∝ Rate × × ↓Normalizing all the typical values for HL GRBs to 1 Hence, we can expect flares and LL GRBs are important!

  15. Neutrino Predictions in the Swift Era KM & Nagataki, PRL, 97, 051101 (2006) KM, Ioka, Nagataki, & Nakamura, ApJL, 651, L5 (2006) See also, Gupta & Zhang 07 HL GRBs Possible dominant contribution in the very high energy region Flares (Eflare,γ = 0.1 EGRB,γ ) LL GRBs (ELL,γ ~ 0.001 EGRB,γ ) ν flashes → Coincidence with flares/early AGs, a few events/yr νs from LL GRBs → little coincidence with bursts, a few events/yr Approaches to GRBs through high-energy neutrinos Flares→information on flare models (baryonic or nonbaryonic etc.) LL GRBs→νs as an indicator of far SNe associated with LL GRBs

  16. Notes on Early Afterglow Emission Prompt shallow decay Its origin is still controversial... ・Forward Shock Model (energy injection etc.) ・Reverse Shock Model (Genet et al. 07, Beloborodov 07) ・Late Prompt Emission Model (Ghisellini et al. 07) steep decay t KM, PRD, 76, 123001 (2007) high baryon loading EHECR ~ EGRB,γ fiducial baryon loading EHECR ~ Eshallow,γ ~ 0.1 EGRB,γ (For forward shock νs, see Dermer 02, 07) • Typically Eshallow,γ ~ 0.1 EGRB,γ (Liang et al. 07) • RS-FS model: ν-detection by IceCube would be difficult… • Late prompt emission model: ν-detection may be possible.

  17. Meszaros (2001) Below Photosphere TeV ν (Meszaros & Waxman 01) (Schneider et al. 02) ( Razzaque, Meszaros, & Waxman 03)

  18. Below/Around Photosphere Below/around the photosphere (even inside the star) Cosmic-ray acceleration could be still expected (e.g., Meszaros & Waxman 01, Razzaque et al. 03) (pp optical depth) ~ np σpp(r/Γ) >~ 0.1 →pp reaction important pp reaction → based on Geant4 & SYBILL codes r=1012.5 cm Γ=100, UB=0.1Uγ strong meson/muon cooling ↓ kaon-contribution is important (Ando & Beacom 05) (Asano & Nagataki 06)

  19. Neutrinos and Progenitor termination shock Termination shock → shock dissipation → thermalization ~keV → providing target photons (Meszaros & Waxman 01) Fig. from Razzaque, Meszaros, & Waxman Schneider et al. (POPIII) Precursor = successful GRBs (GRB rate) Choked = failed GRBs (SN Ibc rate) (pp neutrinos are not shown→) Fabio, KM et al., ApJ (08)

  20. Connection betweenAstrophysical Neutrino Sources and High-Energy Cosmic-Rays

  21. GRB-UHECR Hypothesis The original argument (Waxman 95, Vietri 95) Comparable Possible but requiring high baryon loading… (Lower local rate leads to higher baryon load…) ← UHECR-normalization (except for Flares) KM, PRD, 76, 123001 (07) HL Prompt ~ 30 events/yr LL Prompt ~ 10 events/yr AG (ISM) ~ 0.1 events/yr AG (WIND) ~ 1 event/yr Flare ~ 2 events/yr (not UHECR source)

  22. Notes: HL/LL GRBs and UHECRs KM, Ioka, Nagataki, & Nakamura, submitted (2008) UHECR production is possible in low-luminosity GRBs The source number density ← PAO, TA Burst Models →Sensitive to effective EGMF strength (structured + intergalactic) Necessity of future observations and theoretical studies (see talk by Dr. Takami)

  23. Notes: Heavy Nuclei? Wang, Razzaque, & Meszaros (2008) KM, Ioka, Nagataki, & Nakamura, submitted (2008) Recent PAO results → (tentative) existence of heavier nuclei (Unger et al. 07) UHE nuclei production in GRBs (IS, RS, and FS models) and hypernovae → Possible at enough large radii r Survival of UHE heavy nuclei → neutrino “dark” → TeV gamma-ray “bright” <escape of TeV gamma-rays> + secondary delayed emission (Totani 98, Asano & Inoue 07) (KM, Asano, & Nagataki, ApJ (07), Takahashi, KM, et al., in prep. (08)) (talk by Dr. Asano) Γ=102.5 Γ=1000

  24. Neutrinos from AGN The most frequently discussed UHECR candidates (talk by Prof. Blandford, Dr. Inoue) Many theoretical papers on neutrinos (Szabo & Protheroe, Stecker et al., Rachen & Biermann, Muniz & Meszaros, Mannheim, Atoyan & Dermer…) Ex.) Giant AGN Flare model (Farrar & Gruzinov 08) r=1017.5 cm Γ=10 Muon event rate ~(0.1-1) events/yr

  25. Neutrinos from Clusters of Galaxies KM, Inoue & Nagataki, to be submitted (08) KM, Inoue, & Nagataki, in prep. (08) Cluster shocks (e.g., accretion shocks) → Emax ~ Z 1019 eV may be possible CGs ⇔ The origin of second knee cosmic-rays?? Broken PL required SN shock + CG shock Shock radius ~ virial radius → Muon events ~ a few events/yr Diffusion from Central AGN Model (Berezinsky et al., Colafrancesco & Blasi) Broken PL spectrum → (0.1-1)% of EGRET limit (See talk by Dr. Inoue)

  26. GZK Neutrinos Takami, KM, Nagataki, Sato (08) PAO limit Auger 07 limit Emax=1022eV CMB+CIB (Best-fit model of Kneiske et al. 04) • Ankle model vs dip model → dip model leads to 10 PeV bump • Strong evolution model → detection in the near future • (Yukusel & Kistler 07)

  27. High-Energy Neutrinos and GRBs: Summary • We have performed more sophisticated calculations on neutrino spectra under the internal/external model. →Our results have been tested by AMANDA/IceCube. • We have predicted new possibilities of neutrino emission from GRBs, motivated by Swift observations. 1. Neutrinos from flares and early afterglows 2. Neutrino bursts from low luminosity (LL) GRBs • We can also expect other neutrino signals (CG, AGN etc). • Neutrinos (and gamma-rays) are useful as a probe of cosmic-ray acceleration in astrophysical sources. • If detected, we can obtain the important clues to models of the source and cosmic-ray acceleration. • The connection between GRBs and UHECRs? • High energy neutrino astronomy will come soon!

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