april 23, 2009ps638 tom gaisser 1 neutrinos from agn & grb expectations for a km 3 detector

April 23, 2009 PS638Tom Gaisser

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Neutrinos from AGN & GRB

Expectations for a km3 detector


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Cosmic-ray factories?

Artist’s(*) conception of a massive, accreting, compact with accretion disk and relativistic jets

* Artist = Todor Stanev


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Active Galaxies: JetsActive Galaxies: Jets

VLA image of Cygnus A

Radio Galaxy 3C296 (AUI, NRAO). --Jets extend beyond host galaxy.

Drawing of AGN core

M. Urry, astro-ph/0312545


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Spectral Energy Distribution for blazars

Figure from Markus Bötcher, Astrophys. Space Sci 309 (2007) 95-104


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- 10 seconds

fireball protons interact with remnant

of the star

0 seconds

fireball protons and

photons interact

afterwards

afterglow protons interact with inter-

stellar medium

TeV

PeV

EeV

Image: W. Zhang & S. WoosleySee astro-ph/0308389v2

Jet breakout in GRB following collapse of massive progenitor star


6Slide from Alexander Kappes


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Energy content of extra-galactic component depends on location of

transition• Composition signature: transition back to protons

Uncertainties:• Normalization point:

1018 to 1019.5 usedFactor 10 / decade

• Spectral slope =2.3 for rel. shock =2.0 non-rel.

• Emin ~ mp (shock)2


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Power needed for extragalactic cosmic rays assuming transition at 1019 eV

• Energy density in UHECR, CR ~ 2 x 10 erg/cm3

– Such an estimate requires extrapolation of UHECR to low energy CR = (4/c) E(E) dE = (4/c){E2(E)}E=1019eV x ln{Emax/Emin}

– This gives CR ~ 2 x 10 erg/cm3 for differential index = 2, (E) ~ E-2

• Power required ~ CR/1010 yr ~ 1.3 x 1037 erg/Mpc3/s– Estimates depend on cosmology and extragalactic magnetic fields:– 3 x 10-3 galaxies/Mpc3 5 x 1039 erg/s/Galaxy– 3 x 10-6 clusters/Mpc3 4 x 1042 erg/s/Galaxy Cluster– 10-7 AGN/Mpc3 1044 erg/s/AGN– ~1000 GRB/yr 3 x 1052 erg/GRB

• Assume E-2 spectrum. Then signal ~ 10 to 100/km2yr

– ~20% have E>50 TeV (greater than atmospheric background)


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GRB model

• Assume E-2 spectrum at source, normalize @ 1019.5

• 1045 erg/Mpc3/yr• ~ 1053 erg/GRB• Evolution ~ star-formation rate• GZK losses included• Galactic extragalactic

transition ~ 1019 eV

Bahcall & Waxman, hep-ph/0206217Waxman, astro-ph/0210638


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Berezinsky et al. AGN

• Assuming a cosmological distribution of sources with:– dN/dE ~ E-2, E < 1018 eV– dN/dE ~ E, 1018< E < 1021

– = 2.7 (no evolution)– = 2.5 (with evolution)

• Need L0 ~ 3 ×1046 erg/Mpc3 yr

• They interpret dip at 1019 as– p + 2.7p + e+ + e-

Berezinsky, Gazizov, Grigorieva astro-ph/0210095


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Allard, Olinto, Parizot, astro-ph/0703633

Or start with a model of the extra-galactic component

Subtract it from the observed spectrum to get the galactic component

What is power needed for extra-galactic CR?

3 x 1017eV3 X 1018 eV


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Model dependence of composition in galactic-extragalactic transition

Allard, Olinto, Parizot, astro-ph/0703633

proton model mixed model

• Model extragalactic component• Subtract from observed to get galactic component


14Heavies at end of galactic

Extra-galactic protons

Berezhko & Völk

arXiv:0704.1715v1 [astro-ph]

• Model galactic component• Subtract from observed to get extragalactic

Transition predicted:

1016.5 to 1017.5 eV

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Detecting neutrinos

• Rate– Convolution of:

• Neutrino flux• Absorption in Earth• Neutrino cross section• Range of muon• Size of detector

Probability to detect-induced muon:


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Neutrino effective area

• Rate:

= ∫(E)Aeff(E)dE

• Earth absorption– 10-100 TeV

• cos() > -0.8• Main effect near

vertical

– Higher energy ’s absorbed at larger angles


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IceCube acceptance, resolution

Review of Particle Astrophysics Iowa State University, March 3, 2003

Thomas K. Gaisser18

Expected signals in km3

• Possible point sources:– Galactic

• SNR 0 - 10 events / yr• -quasars 0.1 - 5 / burst

~ 100 / yr, steady source• Magnetars ~ 30 events / yr

– Extra-galactic• AGN jets 0-100 / yr• GRB precursor (~100 s)

– ~ 1000 bursts / yr– ~ 0.2 events / burst

• GRB jet after breakout– smaller mean signal / burst

• Nearby bursts give larger signal in both cases

1800 / yr

20030

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< 1

~ 1

charm

Diffuse (unresolved) sources--signature:• hard spectrum • charm background uncertain


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Limits on excess of above atmospheric background


20Jim Braun, UW Madison, presented at Cosmo-08

Point source search with 7 years of AMANDA 3.8 yrs livetime 26 candidate sources


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Search for neutrinos from GRB

Cascade(Trig & Roll)

Cascade(Rolling)

search

All flavor limits by AMANDAGRB models

Waxman-BahcallPRL 78 (1997) 2292

Murase-Nagataki APRD 73 (2006) 063002

Supranova,Razzaque et al.PRL 90 (2003) 241103

Choked burstsMeszaros-WaxmanPRL 87 (2001) 171102

Limits on neutrinos from GRB from AMANDA: -from cascades (e, ), Ap.J. 664 (2007) 397-from neutrino-induced muons, Ap.J (to be published)

april 23, 2009ps638 tom gaisser 1 neutrinos from agn & grb expectations for a km 3 detector

Documents

2009ps638 tom gaisser

e max e

p e e berezinsky

detector slide

astroph0312545 slide

astroph0210638 slide

ev x ln

alexander kappes slide