neutrinoastronomy

francis halzen

University of Wisconsin http://icecube.wisc.edu menu

• neutrino astronomy • cosmic ray accelerators and neutrinos: Æ km3 neutrino detectors • Amanda and Antares: first generation detectors ~ 0.015 km3 • IceCube • results: Æ neutrino astronomy Æ muon astronomy (?) Æ dark matter search energy (eV)

/ / / / / ν / CMB

Radio / / TeV sources

Visible / cosmic flux / / rays / / -rays / γ / / / GeV menu

• neutrino astronomy • cosmic ray accelerators and neutrinos: Æ km3 neutrino detectors • Amanda and Antares: first generation detectors ~ 0.015 km3 • IceCube • results: Æ neutrino astronomy Æ muon astronomy (?) Æ dark matter search nature’s accelerators ?

protons > 108 TeV photons > 102 TeV neutrinos > 102 TeV galactic and extragalactic cosmic rays galactic extragalactic

sources? based on energetics

galactic: supernova remnants

extragalactic: gamma ray bursts active galaxies

conclusive evidence? Hillas formula : it is not possible

R E gyro ( = ) ≤ E qB R ≤qBR E ≤ c qBR Rotationsakse pulsar Straling

Magnetfelt 2πR v → T Straling 2π 2 __ E (eV) = B (Tesla) R (m) T

ms-pulsar Fermilab R 10 km few km B108 Tesla few Tesla T-1 103 105 (#revs-1)

E107 TeV ~1012 eV = 1 TeV !

still a very open problem… shock acceleration (solar flare)

coronal mass ejection Æ > 10 GeV particles cassiopeia A supernova remnant in X-rays

10-3 of energy released transformed into acceleration

acceleration when particles cross high B-fields large magnetic field in young supernova remnants and if the star collapses to a black hole … collapse of massive star produces a

gamma ray burst

spinning black hole neutrinos are produced in the interactions of protons with synchrotron photons active galaxy particle flows near supermassive black hole M87 / Virgo A ν andNeutrino γ beamsBeams: : heaven Heaven and& Earth earth NEUTRINO BEAMS: HEAVEN & EARTH

black hole

radiation enveloping black hole

p + γ Æ n + π+ ~ cosmic ray + neutrino Æ p + π0 ~ cosmic ray + gamma neutrino astronomy kilometer-scale detectors have the capability of detecting astrophysical neutrinos from cosmic sources with an energy density in neutrinos comparable to their energy density in the observed cosmic rays and TeV gamma rays requires kilometer-scale neutrino detectors Å 5σ in 5 years proton astronomy ? pointing of cosmic rays : d dB θ ≅ = Rgyro E

⎛ d ⎞⎛ B ⎞ ⎜ ⎟ ⎜ ⎟⎜ −9 ⎟ ϑ 1Mpc ⎝10 Gauss ⎠ ≅ ⎝ ⎠ 0.1° E 3×1020 eV B ~ 10-6 Gauss in local cluster ? Auger : the sources revealed ? cosmic rays interact with the microwave background p + γ → n + π +

π → μ + υ cosmic rays disappear, neutrinos appear

π → μ + υ μ → {e + υ μ + υ e} + υ μ

6 Eυ ≥ 2 × 10 TeV 1 event per kilometer squared per year cosmic rays interact with the microwave background p + γ → n + π +

400 cm −3 10 −28 cm2

−1 λint = {ncmbσγ + p } ~10Mpc

7 E p ≥ 5 ×10 TeV TeV gamma ray astronomy : the atmosphere as a photon detector

CANGAROO III

H.E.S.S. gamma detection of ray TeV gamma rays with Cherenkov air shower ~ 10 km telescopes

~ 1o t h ig l v o k n e r e h C

~ 120 m TeV survey instruments ~ 2-3 π

“threshold” sensitivity (1y)

Milagro ~ 2 TeV ~ 0.5 Crab Tibet III shower array ~ 3 TeV ~ 1 Crab ARGO YBJ 0.5 – 1 TeV ~ 0.5 Crab Milagro Crab signal ARGO Tibet array requires kilometer-scale neutrino detectors Å 5σ in 5 years Galactic cosmic rays… galactic plane in 10 TeV gamma rays : supernova remnants in star forming regions Standard Deviations Southern Hemisphere Sky

90° 65° 30°

210° γ, ν flux of galactic cosmic rays

a SNR at d = 1 kpc transfers W = 1050 erg to cosmic rays interacting with molecular clouds with density n = 1 cm-3 dN E γ (>1TeV ) = dE ph W n d =10−11 ( )−2 cm2s 1050 erg 1cm3 1kpc

2 SNR per century supply the observed density of galactic cosmic rays e.g. RX J1713.7-3946 neutrinos from supernova remnants :

molecular clouds as beam dumps neutral pions π0 π+ π- are observed as + - gamma rays γ γ νμ μ ν μ e+ e- charged pions + - are observed as e γ e + neutrinos e+ γ μ + e νe νμ μ ν +ν μ = γ + γ arXiv:0902.3022 for detailed statistical analysis

simulated IceCube map 5 years (E > 40 TeV) extragalactic cosmic rays … active galaxy

Centaurus A M87 Fornax A … supermassivesupermassive blackblack holehole

•accretion disk

•jet spectral energy distribution of Cen A (variability!)

Magic M87! energy (eV)

/ / galactic / cosmic rays / 10-12 erg/cm3 galactic / cosmic rays/ CMB 10-41 erg/cm3

Radio / / extragalactic cosmic rays

Visible / flux / 10-19 erg/cm3 410 photons / of 2.7 K / -12 3 / or 10 erg/cm -rays / γ / / / GeV Æ energy in extra-galactic cosmic rays is ~ 3x10-19 erg/cm3

3x1044 erg/s per active galaxy 2x1052 erg per gamma ray burst energy in cosmic rays ~ photons~ neutrinos galactic and extragalactic cosmic rays

knee

1 event ankle km-2 yr-1 extragalactic cosmic rays flux of neutrinos is roughly equal to the flux of extra- galactic cosmic rays

ankle Æ one 1019 eV particle per km squared per year per sr

dN 1019 eV E 2 = dE (1010 cm2 )(3×107 sec) sr

= 3×10−11 TeV cm−2 sec−1 sr −1 total flux = velocity x density : 4π dE dN ) ( E d = c ∫ E E ρ ρ 4π 3×10−11 TeV = dE E c ∫ E cm3

Emax −19 TeV = ⋅⋅⋅log ≅ 10 3 Emin cm Waxman-Bahcall Flux π + π 0 oscillations

1 1 1 d H Φν = × × ×ΦCR × ≅ ΦCR 2 2 2 dCMB

ν μ + ν μ in π+ decay ν e + e )

V

( Te

dE E 6

μ −

→ 0 ν 1 events P

1

N E − d d 500 sr ∫

1 ≅ − × s

2 − max min

ν ν time cm E E ×

TeV log

11 × area − × 10 E π 80 ×

2 ≅ 5 =

N N • per km2 year: events neutrinos associated with extragalactic cosmic rays

AMANDA

IceCube neutrino astronomy: rationale for km3 kilometer-scale detectors have the capability of detecting astrophysical neutrinos from cosmic sources with an energy density in neutrinos comparable to their energy density in the observed cosmic rays and TeV gamma rays

Æ this is the case for supernova remnants

Æ this is the case for active galaxies and gamma ray burst

“IF” they are the sources of the cosmic rays