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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. - PowerPoint PPT Presentation
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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
MACROS 2013 , IAP, Nov. 27-29, 2013
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 UHECRs1. AGN (Berezinsky..)
2. GRB (Waxman, Vietri, …)
Hillas Plot
3 Galaxy clusters ( Inoue..) Pulsars (Fang…) Hypernova …
R_L<R B*R>E/Zqv
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?
[Waxman 95; Bahcall & Waxman 03]
yrerg/Mpc10~Const./ 35.432 ppp dnd
• require Galactic sources up to ~1018.5eV
• 1/E2 source spectrum
Uncertainties:
1 ) Local GRB rate R_0
2 ) ECR/Eγ =? (Eγ =Ee)
GRB: E_γ=1E52.5 erg , R_0=1/Gpc^3/yr
yrerg/Mpc10yr Gpc/1erg10/ 35.43-135.522 dnd
UHECR flux
GRB flux
Hypernova model for UHECRs
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 )
Wang, Razzaque, Meszaros, Dai 2007, PRD
Nearby hypernova/GRBs
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 withenergy >1e50 erg
Name Distance comments
SN1998bw 38 Mpc GRB980425
SN2006aj 120 Mpc GRB060218
SN 2010bh 260 Mpc GRB100316D
SN2009bb 40 Mpc No GRB associated
SN 1998bw
Hypernova model for UHECRs
v=c , Z=26
v=0.1c
R_L<R B*R>E/Zqv
Chakraborti et al. 2010
Energy spectrum
WR stellar wind Hypernova ejecta (SN1998bw)
p=2 p=2
Liu & Wang 2012
GRB Neutrino prediction
He/CO starH envelope
Buried shocksNo -ray emission
Razzaque, Meszaros & Waxman ’03Murase & Ioka ‘13
Precursor ’s
Internal shocksPrompt -ray (GRB)
Waxman & Bahcall ’97Murase & Nagataki 07Wang & Dai 09, Murase 08
Burst ’s
External shocksAfterglow X,UV,O
Waxman & Bahcall ’00
Afterglow ’s
p
PeV EeVGeV/TeV
22GeV3.0 p
Neutrino production in GRBs Necessary conditions: Proton energy fraction:1. Proton-electron composition :Ep/Ee= ~10 (assumption)
2. 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
Liang et al. 2010 Ghirlanda et al. (2012)
Constraints on the baryon ratioEp/Eγ
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)
• 28 events• significance > 4 sigma atm. Background
:up
down
0.56.36.10
II. Diffuse TeV-PeV neutrinos
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
Simulated sample : comparison with Fermi/GBM GRBs
Liu & Wang, 2013
We use simulated GRB sample to include dim 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
Untriggered GRBs produce 2 times larger flux
Total flux
Normal GRB population insufficient to account for two PeV neutrinos !
Liu & Wang 2013
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 General consideration--connect to UHECRs?
Required energy (ankle transition): Required energy (second knee):
1PeV neutrino:
Liu, Wang, Inoue, Crocker, Aharonian 2013, arXiv:1310.1263
HN acceleration ?
See also Katz et al. ‘13
Hypernova remnant scenario
pp efficiency
Two escape ways: 1) diffusion 2) advection
Hypernovae occur in star-forming galaxies & starburst galaxies
ISMProton
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 thediffuse isotropic gamma ray background