ne and nµ are absorbed in the Earth via charged current interactions (muons range out)
Above ~100 TeV the Earth is opaque to ne & νµ.
But, the Earth never becomes completely opaque to nt
Due to the short t lifetime, t’s produced in nt charged-current interactions decay back into nt
Also, secondary ne & νµ. fluxes are produced in the tau decays.
The ratio of flavors at the source is expected to be 0:2:1= nt : nm : ne
Since the distance to the source is >> than the oscillation length – any admixture at the source should wind up:
1:1:1= nt : nm : ne
when arriving at earth
What if that isn’t true?
Exotic neutrino properties if not 1:1:1
Neutrino decay (Beacom, Bell, Hooper, Pakvasa& Weiler)
CPT violation (Barenboim& Quigg)
Oscillation to steriles with very tiny delta δm2
(Crocker et al; Berezinskyet al.)
Pseudo-Dirac mixing (Beacom, Bell, Hooper, Learned, Pakvasa& Weiler)
3+1 or 2+2 models with sterile neutrinos (Dutta, Reno and Sarcevic)
Magnetic moment transitions (Enqvist, Keränen, Maalampi)
Varying mass neutrinos (Fardon, Nelson & Weiner; Hung & Pas)
60% of Galaxy
95% of Galaxy
up to LMC
Large Scale Neutrino Detectors
IceCube, South Pole, Antarctica
See Talks in this Session
Radio Cherenkov Detectors
Rice Anita Salsa
SAUND (Study of Acoustic Underwater Neutrino Detection)
Now Soon Future
Amanda Cherenkov arrays ???
SK Radio Detectors
Neutrino Astronomy is just beginning to open a new window on the Universe!