Charged Cosmic Rays and Neutrinosweb.phys.ntnu.no/~mika/now12.pdf · 2012-09-14 · (resonant)...
Transcript of Charged Cosmic Rays and Neutrinosweb.phys.ntnu.no/~mika/now12.pdf · 2012-09-14 · (resonant)...
[]
Charged Cosmic Rays and Neutrinos
Michael Kachelrieß
NTNU, Trondheim
Introduction
Outline of the talk1 Introduction ⇒ talk by F. Halzen
2 SNRs as Galactic CR sources
3 Extragalactic CRs
◮ transition
◮ anisotropies
◮ composition measurements
4 Astrophysical source models ⇒ talks of S. Ando & F. Halzen
5 Cosmogenic neutrinos
6 Summary
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 2 / 25
Introduction
Outline of the talk1 Introduction ⇒ talk by F. Halzen
2 SNRs as Galactic CR sources
3 Extragalactic CRs
◮ transition
◮ anisotropies
◮ composition measurements
4 Astrophysical source models ⇒ talks of S. Ando & F. Halzen
5 Cosmogenic neutrinos
6 Summary
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 2 / 25
Introduction
Outline of the talk1 Introduction ⇒ talk by F. Halzen
2 SNRs as Galactic CR sources
3 Extragalactic CRs
◮ transition
◮ anisotropies
◮ composition measurements
4 Astrophysical source models ⇒ talks of S. Ando & F. Halzen
5 Cosmogenic neutrinos
6 Summary
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 2 / 25
Introduction
The CR–γ–ν connection:
HE neutrinos and HE photons are unavoidable byproducts of HECRs
astrophysical models, direct flux:◮ strongly model dependent fluxes
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 3 / 25
Introduction
The CR–γ–ν connection:
HE neutrinos and HE photons are unavoidable byproducts of HECRs
astrophysical models, direct flux:◮ strongly model dependent fluxes
astrophysical models, cosmogenic flux:◮ ratio Iν/IN determined by nuclear composition and source evolution
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 3 / 25
Introduction
The CR–γ–ν connection:
HE neutrinos and HE photons are unavoidable byproducts of HECRs
astrophysical models, direct flux:◮ strongly model dependent fluxes
astrophysical models, cosmogenic flux:◮ ratio Iν/IN determined by nuclear composition and source evolution
top-down models:◮ large fluxes with Iν ≫ Ip
◮ ratio Iν/Ip fixed by fragmentation
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 3 / 25
Introduction
The CR–γ–ν connection:
HE neutrinos and HE photons are unavoidable byproducts of HECRs
astrophysical models, direct flux:◮ strongly model dependent fluxes
astrophysical models, cosmogenic flux:◮ ratio Iν/IN determined by nuclear composition and source evolution
top-down models:◮ large fluxes with Iν ≫ Ip
◮ ratio Iν/Ip fixed by fragmentation
prizes to win:◮ astronomy above 100 TeV◮ identification of CR sources◮ determine galactic–extragalactic transition of CRs◮ test/discover new particle physics
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 3 / 25
[]
[]
Diffusive shock acceleration in test particle picture:
energy spectrum dN/dE ∝ 1/E2
escape flux dN/dr ∝ exp(−(r − Rsh)/x0) for r > Rsh
SNRs as CR sources
SNR: Leptonic versus hadronic models [⇒ Giordano ]
Test the SNR CR acceleration paradigm through SNR’s particle radiation:
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 5 / 25
SNRs as CR sources
SNR: Leptonic versus hadronic models [⇒ Giordano ]
Test the SNR CR acceleration paradigm through SNR’s particle radiation:
combining Fermi and IACT contrains models tightly
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 5 / 25
SNRs as CR sources
Maximal energy of SNR: Lagage-Cesarsky limit
acceleration rate
βacc =dE
dt
∣
∣
∣
∣
acc
=3Ev2
sh
ζD(E), ζ ∼ 8 − 20
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 6 / 25
SNRs as CR sources
Maximal energy of SNR: Lagage-Cesarsky limit
acceleration rate
βacc =dE
dt
∣
∣
∣
∣
acc
=3Ev2
sh
ζD(E), ζ ∼ 8 − 20
assume Bohm diffusion D(E) = cRL/3 ∝ E and B ∼ µG
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 6 / 25
SNRs as CR sources
Maximal energy of SNR: Lagage-Cesarsky limit
acceleration rate
βacc =dE
dt
∣
∣
∣
∣
acc
=3Ev2
sh
ζD(E), ζ ∼ 8 − 20
assume Bohm diffusion D(E) = cRL/3 ∝ E and B ∼ µG
⇒ Emax ∼ 1013—1014 eV
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 6 / 25
SNRs as CR sources
Maximal energy of SNR: [Bell, Luzcek ’02, Bell ’04 ]
(resonant) coupling CR ↔ Alfven waves
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 7 / 25
SNRs as CR sources
Maximal energy of SNR: [Bell, Luzcek ’02, Bell ’04 ]
(resonant) coupling CR ↔ Alfven waves
non-linear non-resonant magnetic field amplification
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 7 / 25
SNRs as CR sources
Maximal energy of SNR: [Bell, Luzcek ’02, Bell ’04 ]
(resonant) coupling CR ↔ Alfven waves
non-linear non-resonant magnetic field amplification
observational evidence for B ∼ 0.1 − 1 mG in young SNR rims
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 7 / 25
SNRs as CR sources
SNR RX J1713.7-3946
/%��#�����������������;��"
� �7���!��������;��"
changes on δt ∼ 1 yr imply B ∼ 1mG⇒ Emax ∼ 1016 eV for protons
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 8 / 25
SNRs as CR sources
Tycho observations by VERITAS
Γ = 1.95 ± 0.51stat ± 0.30sys
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 9 / 25
SNRs as CR sources
Tycho observations by VERITAS
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 9 / 25
SNRs as CR sources
Tycho observations by VERITAS
CRs escape before Sedov phase
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 10 / 25
SNRs as CR sources
Tycho observations by VERITAS
CRs escape before Sedov phaseEγ,max >10 TeV requires:
◮ protons with E > 100 TeV
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 10 / 25
SNRs as CR sources
Tycho observations by VERITAS
CRs escape before Sedov phaseEγ,max >10 TeV requires:
◮ protons with E > 100 TeV◮ electrons, ICS on CMB
Eγ =4
3
εγE2
e
m2e
≈ 3 GeV
(
Ee
1TeV
)2
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 10 / 25
SNRs as CR sources
Tycho observations by VERITAS
CRs escape before Sedov phaseEγ,max >10 TeV requires:
◮ protons with E > 100 TeV◮ electrons, ICS on CMB
Eγ =4
3
εγE2
e
m2e
≈ 3 GeV
(
Ee
1TeV
)2
electrons with E > 50 TeV
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 10 / 25
SNRs as CR sources
Tycho: Leptonic versus hadronic models [Morlino, Capriolo ’11 ]
Radio
Suzaku
FermiLAT
VERITAS
10 15 20 259.5
10.0
10.5
11.0
11.5
12.0
12.5
13.0
13.5
LogHΝL @HzD
LogHΝ
FΝL@J
yH
zD
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 11 / 25
SNRs as CR sources
Why is there a universal CR spectrum?age-limited
◮ CRs are advected down-stream, released at end of Sedov phase– adiabatic losses, reduced Emax, no B amplification
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 12 / 25
SNRs as CR sources
Why is there a universal CR spectrum?
age-limitedCRs escape up-stream:
◮ standard approach: homogeneous field & free escape boundary
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 12 / 25
SNRs as CR sources
Why is there a universal CR spectrum?
age-limitedCRs escape up-stream:
◮ standard approach: homogeneous field & free escape boundary◮ filamentation instability: [Reville, Bell ’11 ]
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 12 / 25
SNRs as CR sources
Why is there a universal CR spectrum?
age-limitedCRs escape up-stream:
◮ standard approach: homogeneous field & free escape boundary◮ filamentation instability: [Reville, Bell ’11
]
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 12 / 25
Transition from Galactic to extragalactic CRs Nuclear composition
Transition – KASCADE Grande data
energy (eV/particle)
1410 1510 1610 1710 1810 1910 2010
]1.
5 e
V-1
sr
-1 s
-2 [
m2.
5 E·
dI/d
E
1310
1410
1510
1610
1710
Grande QGSJETII, all-particle (this work)Grande QGSJETII, hydrogen (this work)Grande QGSJETII, He+C+Si (this work)Grande QGSJETII, iron (this work)KASCADE QGSJETII, all-particle (this work)KASCADE QGSJETII, hydrogen (this work)KASCADE QGSJETII, He+C+Si (this work)KASCADE QGSJETII, iron (this work)
Grande QGSJETII, all-particle (this work)Grande QGSJETII, hydrogen (this work)Grande QGSJETII, He+C+Si (this work)Grande QGSJETII, iron (this work)KASCADE QGSJETII, all-particle (this work)KASCADE QGSJETII, hydrogen (this work)KASCADE QGSJETII, He+C+Si (this work)KASCADE QGSJETII, iron (this work)
EAS-TOP, all-particleAkeno, all-particleHiRes II, all-particleGAMMA, all-particleTibet, all-particle
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 13 / 25
Transition from Galactic to extragalactic CRs Nuclear composition
Transition – KASCADE Grande data
energy (eV/particle)
1410 1510 1610 1710 1810 1910 2010
]1.
5 e
V-1
sr
-1 s
-2 [
m2.
5 E·
dI/d
E
1310
1410
1510
1610
1710
Grande QGSJETII, all-particle (this work)Grande QGSJETII, hydrogen (this work)Grande QGSJETII, He+C+Si (this work)Grande QGSJETII, iron (this work)KASCADE QGSJETII, all-particle (this work)KASCADE QGSJETII, hydrogen (this work)KASCADE QGSJETII, He+C+Si (this work)KASCADE QGSJETII, iron (this work)
Grande QGSJETII, all-particle (this work)Grande QGSJETII, hydrogen (this work)Grande QGSJETII, He+C+Si (this work)Grande QGSJETII, iron (this work)KASCADE QGSJETII, all-particle (this work)KASCADE QGSJETII, hydrogen (this work)KASCADE QGSJETII, He+C+Si (this work)KASCADE QGSJETII, iron (this work)
EAS-TOP, all-particleAkeno, all-particleHiRes II, all-particleGAMMA, all-particleTibet, all-particle
rising proton fraction E >∼
1017 eV?
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 13 / 25
Transition from Galactic to extragalactic CRs Anisotropies
PAO result on dipole anisotropy:
[EeV] E0.3 1 2 3 4 5 10 20
Am
plitu
de
-310
-210
-110
1
Rayleigh AnalysisEast/West Analysis
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 14 / 25
Transition from Galactic to extragalactic CRs Anisotropies
PAO result on dipole anisotropy:
[EeV] E0.3 1 2 3 4 5 10 20
]°P
hase
[
180
270
0
90
180
East/West analysisRayleigh analysis
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 14 / 25
Transition from Galactic to extragalactic CRs Anisotropies
Anisotropy of protons at E = 1018 eV [Giacinti et al. ’11 ]
10
15
20
25
30
35
40
2 3 4 5 6 7 8
Dip
ole
ampl
itude
(pe
rcen
t)
B0 (µG)
Profile 2, 200 pcProfile 1, 200 pcProfile 2, 500 pcProfile 1, 500 pc
protons excluded for all reasonable parameters
⇒ measuring protons at E = 1018 eV means fixing transition energy
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 15 / 25
Nuclear composition
Energy spectrum
PAO confirmed the “GZK-suppression” seen first by HiRes
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 16 / 25
Nuclear composition
Energy spectrum
PAO confirmed the “GZK-suppression” seen first by HiRes
interpretation:◮ Emax of sources?◮ does not fix composition: proton GZK, Fe photo disintegration
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 16 / 25
Nuclear composition
Determining nuclear composition: Xmax and RMS(Xmax)Bethe-Heitler model: Nmax ∝ E0 and Xmax ∝ ln(E0)
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 17 / 25
Nuclear composition
Determining nuclear composition: Xmax and RMS(Xmax)Bethe-Heitler model: Nmax ∝ E0 and Xmax ∝ ln(E0)
superposition model: nuclei = A shower with E = E0/A
⇒ Xmax ∝ − ln(A) and RMS(Xmax) reduced
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 17 / 25
Nuclear composition
Determining nuclear composition: Xmax and RMS(Xmax)Bethe-Heitler model: Nmax ∝ E0 and Xmax ∝ ln(E0)
superposition model: nuclei = A shower with E = E0/A
⇒ Xmax ∝ − ln(A) and RMS(Xmax) reduced
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 17 / 25
Nuclear composition
Determining nuclear composition: Xmax and RMS(Xmax)Bethe-Heitler model: Nmax ∝ E0 and Xmax ∝ ln(E0)
superposition model: nuclei = A shower with E = E0/A
⇒ Xmax ∝ − ln(A) and RMS(Xmax) reduced
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 17 / 25
Nuclear composition
Determining nuclear composition: Xmax and RMS(Xmax)Bethe-Heitler model: Nmax ∝ E0 and Xmax ∝ ln(E0)
superposition model: nuclei = A shower with E = E0/A
⇒ Xmax ∝ − ln(A) and RMS(Xmax) reduced
RMS(Xmax) has smaller theoretical error than Xmax
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 17 / 25
Nuclear composition
Nuclear composition via Xmax:
/decade] 18 19
]2>
[g/c
mm
ax<X
650
700
750
800
850
proton
iron
QGSJET01QGSJETIISibyll2.1EPOSv1.99
Auger 2009
HiRes ApJ 2005
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 18 / 25
Nuclear composition
Nuclear composition via RMS(Xmax) from Auger:
E [eV]
1810 1910
E [eV]
1810 1910
]2)
[g/c
mm
axR
MS
(X
10
20
30
40
50
60
70 proton
iron
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 19 / 25
Nuclear composition
Mixed composition:
Mean 744.8RMS 62.02
]2 [g/cmmaxX600 650 700 750 800 850 900 9500
0.02
0.04
0.06
0.08
0.1
0.12
Mean 744.8RMS 62.02
70% proton
30% iron
sum
σ2 =∑
i
fiσ2i +
∑
i<j
fifj(Xmax,i − Xmax,j)2
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 20 / 25
Nuclear composition
What goes wrong?internal discrepancy in PAO:
◮ AGN correlations favor protons
◮ RMS(Xmax) favors heavy
◮ energy spectrum, Xmax and RMS(Xmax) difficult to fit
experimental discrepancy: HiRes/TA ⇔ Auger
◮ Xmax
◮ RMS(Xmax)
discrepancy experiment ⇔ theory:
◮ energy ground array/fluoresence ∼ 1.2
◮ muon number exp/MC ∼ 1.2 − 2
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 21 / 25
Nuclear composition
What goes wrong?internal discrepancy in PAO:
◮ AGN correlations favor protons
◮ RMS(Xmax) favors heavy
◮ energy spectrum, Xmax and RMS(Xmax) difficult to fit
experimental discrepancy: HiRes/TA ⇔ Auger
◮ Xmax
◮ RMS(Xmax)
discrepancy experiment ⇔ theory:
◮ energy ground array/fluoresence ∼ 1.2
◮ muon number exp/MC ∼ 1.2 − 2
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 21 / 25
Nuclear composition
What goes wrong?internal discrepancy in PAO:
◮ AGN correlations favor protons
◮ RMS(Xmax) favors heavy
◮ energy spectrum, Xmax and RMS(Xmax) difficult to fit
experimental discrepancy: HiRes/TA ⇔ Auger
◮ Xmax
◮ RMS(Xmax)
discrepancy experiment ⇔ theory:
◮ energy ground array/fluoresence ∼ 1.2
◮ muon number exp/MC ∼ 1.2 − 2
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 21 / 25
Nuclear composition
Comparison of MCs to LHC data: Energy flow
'()*'+),-)./00/1)+234/)05/6)7/1/)891024:;91;6)
./0PYTHIA as typical HEP model Cosmic ray interaction models
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 22 / 25
Cosmogenic neutrinos Limit from EGRB
Fermi-LAT limit for cosmogenic neutrinos: [Berezinsky et al. ’10,. . . ]
106 108 1010 1012 1014 1016 1018 1020 102210-2
100
102
104
E2 J(
E), e
V cm
-2s-1
sr-1
E, eV
Fermi LAT
p
zmax=2, Emax=1021eVHiRes
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 23 / 25
Cosmogenic neutrinos Limit from EGRB
Fermi-LAT limit for cosmogenic neutrinos: [Berezinsky et al. ’10,. . . ]
E, eV1810 1910 2010 2110
-1st
er-1
sec
-2m2
J(E
) eV
3E
2310
2410
2510eV; m=021=10
max=2; Emaxz
HiRes II HiRes I
p
iνΣ
2.7
2.0
2.7
2.0
2.0
2.7
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 23 / 25
Cosmogenic neutrinos Limit from EGRB
Fermi-LAT limit for cosmogenic neutrinos: [Berezinsky et al. ’10,. . . ]
0 1 2 3 4 5 610-8
10-7
10-6
10-5
10-4
cas(m
), eV
/cm
3 5
5
6
6
4
4
2
m
5.8x10-7
Emax=1021eV
2
g=2.6g=2.0
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 23 / 25
Cosmogenic neutrinos Limit from EGRB
Fermi-LAT limit for cosmogenic neutrinos: [Berezinsky et al. ’10,. . . ]
1016 1017 1018 1019 1020 1021 102210-1
100
101
102
103
104
105
106
1021
1020
IceCube 5yr tilted
2.0
RICE
Auger diff.
E-2 cascade
ANITA
E2 J(
E), e
Vcm
-2s-1
sr-1
E, eV
ANITA-liteAuger
2.6
nadirJEM-EUSOBAIKAL
e =
1022
m=3
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 23 / 25
Cosmogenic neutrinos Limit from EGRB
Fermi-LAT limit for cosmogenic neutrinos: [Berezinsky et al. ’10,. . . ]
108 1010 1012 101410-2
100
m=0, g=2.0, z
max=2, E
max=1021eV
1 nG
E
2 J(E
), eV
cm
-2s-1
sr-1
E, eV
0.01 nG
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 23 / 25
Cosmogenic neutrinos Dependence on composition
Cosmogenic neutrinos: proton vs. Fe
[Anchordoqui et al. ’07 ]
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 24 / 25
Summary
Summary
Galactic CRs: Tycho: room left for leptonic models marginal
UHECRs:
◮ understanding differences PAO vs. TA and MC vs. experiment
◮ extensions (HEAT, Amiga, infill array) allow cross checks
◮ test of MC models against LHC data
◮ proton dominance at 1018 eV fixes transition energy
cosmogenic neutrino flux is low, because of Fermi limit
2 Icecube events: start of neutrino astronomy?
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 25 / 25
New TA data for Xmax:
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 26 / 25
Zenith angle dependence, TA scintillator:
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 27 / 25
Zenith angle dependence, TA scintillator:
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 27 / 25
Icecube events
Icecube events
2 cascade events close to Emin = 1015 eV, bg = 0.14
•
•
•
energy distributions of neutrinos reaching to the IceCube
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 28 / 25
Icecube events
Icecube events
2 cascade events close to Emin = 1015 eV, bg = 0.14
Glashow resonance◮ very narrow
◮ if W− → q̄q, detected energy too low
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 28 / 25
Icecube events
Icecube events
2 cascade events close to Emin = 1015 eV, bg = 0.14
Glashow resonance
cosmogenic neutrinos: <∼
1 events/yr
[Anchordoqui et al. ’07 ]
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 28 / 25
Icecube events
Icecube events
2 cascade events close to Emin = 1015 eV, bg = 0.14
Glashow resonance
cosmogenic neutrinos: <∼
1 events/yr
extragalactic sources: extension to higher energies?if yes, then diffuse flux
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 28 / 25
Icecube events
Icecube events
2 cascade events close to Emin = 1015 eV, bg = 0.14
Glashow resonance
cosmogenic neutrinos: <∼
1 events/yr
extragalactic sources: extension to higher energies?if yes, then diffuse flux
Galactic point sources: SNR with d ∼ 50 pc
Michael Kachelrieß (NTNU Trondheim) Cosmic Rays and Neutrinos NOW 2012 28 / 25