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MACROS 2013 , IAP, Nov. 27-29, 2013 . Neutrino from GRBs and hypernova remnants. Xiang-Yu Wang Nanjing University, China. Collaborators: H.N. He, R. Y. Liu, K. Murase, S. Inoue, S. Nagataki, Z. G. Dai, R. Crocker, F. Aharonian. Outline.
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MACROS 2013 , IAP, Nov. 27-29, 2013 Neutrino from GRBs and hypernova remnants Xiang-Yu Wang Nanjing University, China Collaborators: H.N. He, R. Y. Liu, K.Murase, S. Inoue, S. Nagataki, Z. G. Dai, R. Crocker, F. Aharonian
Outline • GRB and HNe as a candidate source for ultra-high energy cosmic rays • Neutrino messenger for constraining GRB properties • Could the TeV-PeV neutrinos recently detected by IceCube originate from GRBs or HNe ?
Acceleration of UHECRs 1. AGN (Berezinsky..) R_L<R B*R>E/Zqv Hillas Plot 2. GRB (Waxman, Vietri, …) 3 Galaxy clusters (Inoue..) Pulsars (Fang…) Hypernova …
CR acceleration in GRBs • Internal shocks (Waxamn 95) • External shocks (Vietri 95) Credit: P. Meszaros 1E12-1E13 cm 1E17-1E18 cm
Debating point: GRBs can provide enough CR flux? UHECR flux GRB flux GRB: E_γ=1E52.5 erg, R_0=1/Gpc^3/yr • Uncertainties: • 1)Local GRB rate R_0 • 2)ECR/Eγ =? (Eγ =Ee) • require Galactic sources up to ~1018.5eV • 1/E2 source spectrum [Waxman 95; Bahcall & Waxman 03]
Hypernova model for UHECRs Wang, Razzaque, Meszaros, Dai 2007, PRD • Relativistic analogy of normal SNRs for Galactic CRs • Semi-relativistic shock front can accelerate particles to UHE energies (expanding into the stellar wind of Wolf-Rayet stars )
Nearby hypernova/GRBs SN 1998bw • Radio afterglow modeling of SN1998bw: E>1e49 erg, Γ~1-2 • X-ray afterglow: E~5e49 erg, \beta=0.8 (Waxman 2004) Mildly relativistic ejecta component with energy >1e50 erg
Hypernova model for UHECRs R_L<R B*R>E/Zqv v=c, Z=26 v=0.1c Chakraborti et al. 2010
Energy spectrum Liu & Wang 2012 WR stellar wind Hypernova ejecta (SN1998bw) p=2 p=2
Buried shocks No -ray emission Precursor ’s Razzaque, Meszaros & Waxman ’03 Murase & Ioka ‘13 GRB Neutrino prediction H envelope He/CO star p External shocks Afterglow X,UV,O Internal shocks Prompt -ray (GRB) Afterglow ’s Burst ’s Waxman & Bahcall ’00 Waxman & Bahcall ’97 Murase & Nagataki07 Wang & Dai 09, Murase 08 PeV GeV/TeV EeV
Neutrino production in GRBs • Necessary conditions: • Proton energy fraction: • Proton-electron composition :Ep/Ee= ~10 (assumption) • Poynting-flux dominated jets: very low—detection impossible • Enough thick target • Dense photon field—depend on dissipation radius • Dense medium—optically thick photosphere Ep/Ee= ECR/Eγ =?
IC40+59 results: Non-detection Stacking analysis on 215 GRBs between April 2008 and May 2010 IceCube: Stacked point-source flux limit is below “benchmark” prediction by a factor 3-4.
However, inaccurate calculation by IceCube of the expected flux • 1) Normalization (Li 12, Hummer et al. 12, He et al. 12) • 2) particle physics, realistic photon spectrum,… ---numerical calculation (Hummer+ 12; He+12) IceCube: Correct:
Our result for IC40+59 flux (He, Liu, Wang, Murase, Nagataki, Dai 2012) • For the same 215 GRBs • Using the same benchmark parameters as IceCube team • Our results: stacked neutrino flux from 215 GRBs is still a factor of ~3 below the IceCube sensitvity Benchmark parameters: t_v= 0.01 s Γ = 10^2.5, Baryon ratio Ep/Eγ= 10
Non-benchmark model parameters • Neutrino flux very sensitive to Г • Using more realistic Г Ghirlanda et al. (2012) Liang et al. 2010
General dissipation scenario-constrain the radius R >4 ×10^12 cm • Large dissipation radius scenario (e.g. Magnetic dissipation scenario) • -- OK • Small dissipation radius scenario (e.g. photosphere scenario): • -- Challenged (Zhang & Kumar 2012)
II. Diffuse TeV-PeV neutrinos • 28 events • significance > 4 sigma up atm. Background : down
Origin of the Tev/PeV neutrinos? • Proposed models Cosmogenic nu: No (Roulet+ 2013, Ahlers & Halzen 12) Hadronuclear Origin: Murase, Ahlers & Lacki ’13, He et al. 13 Photonuclear origin: Winter 13 AGNs: Kalashev et al. 13 • Diffuse GRB neutrino? • Theory predictions: Depend on the luminosity function and redshift distribution ( Gupta+ 07; He+ 12; Cholis & Hooper 13) • But did not consider the existing IceCube limit on triggered GRBs
Triggered/un-triggered GRBs Liu & Wang, 2013 We use simulated GRB sample to include dim GRBs • Simulated sample : comparison with Fermi/GBM GRBs
Contribution by un-triggered GRBs • GRBs with10^51–10^53 erg/s contribute the largest • Do not trigger the detectors due to their occurring at relatively high redshifts
Diffuse neutrino emission from triggered and un-triggered GRB Liu & Wang 2013 • Untriggered GRBs produce 2 times larger flux • Total flux • Normal GRB population insufficient to account for two PeV neutrinos !
Contribution by other GRB populations • Low-luminosity GRBs (Murase & Nagataki 06, Liu, Wang, Dai 11, Murase & Ioka 2013) • Pop III GRBs (Gao & Meszaros 12) Larger uncertainties.
Hypernova remnants: pp process Liu, Wang, Inoue, Crocker, Aharonian 2013, arXiv:1310.1263 • General consideration--connect to UHECRs? 1PeV neutrino: HN acceleration ? Required energy (ankle transition): Required energy (second knee): See also Katz et al. ‘13
ISM Hypernova remnant scenario Proton • pp efficiency • Two escape ways: 1) diffusion 2) advection • Hypernovae occur in star-forming galaxies • & starburst galaxies
Neutrino spectrum from HN remnants • SBG: star-burst galaxies • NSF: normal star-forming galaxies • use S=-2.2-2.3
Summary • Neutrino measurements have now put constraints on GRB properties—dissipation radii, composition… • Diffuse GRB neutrinos alone seem insufficient to account for TeV-PeV neutrinos • Hypernova remnants could be a possible source
Comparison – for one burst • Analytic: Delta resonance • Numerical calculation: consider the full cross section, direct pion, multi-pion production channels • Our calculated flux (red curve) is one order of magnitude lower than IceCube collaboration
Neutrino emission For high-redshift star-forming galaxies * The accompanying gamma ray flux remains below the diffuse isotropic gamma ray background