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40 - D.Fargion , D. DArmiento 2010
Neutrinos are allowed to mix and to oscillate among their flavor. Muon and tau in particular oscillate at largest values.Last Minos experiment claimed possible difference among their matter and anti-matter masses, leading to a first violation of the most believed CPT symmetry.Isotropically born atmospheric muon neutrino at 20-80 GeV, while up-going, they might be partially suppressed by mixing in analogy to historical SuperKamiokande muon neutrino disappearance into tau, leading to large scale anisotropy signals. Here we show an independent muon rate foreseen in Deep Core based on observed SK signals extrapolated to DeepCore mass and its surrounding. Our rate prediction partially differ from previous ones. The neutrino muon disappearance into tau is leading to an anisotropy in vertical up-going muon track: in particular along channel 3-5 we expect a huge rate (tens of thousand of events) of neutral current events, charged current electron and inclined crossing muons. Moreover at channel 6-9 we expect a severe suppression of the rate due to muon disappearance (in CPT conserved frame). Such an anisotropy might be partially tested by more than one string detection at E> 45 GeV energy. A CPT violation may induce a more remarkable suppression of vertical up-going tracks because of larger anti-neutrino muon reduction for E> 35 GeV.
100 - D.Fargion , D. DArmiento 2009
Photon Astronomy ruled the last four centuries while wider photon band ruled last radio-X-Gamma century of discovery. Present decade may see the rise and competition of UHECR and UHE Neutrino Astronomy. Tau Neutrino may win and be the first flavor re vealed. It could soon rise at horizons in AUGER at EeV energies, if nucleons are the main UHECR currier. If on the contrary UHECR are Lightest nuclei (He, Li. B) UHE tau neutrino maybe suppressed at EeV and enhanced at tens -hundred PeV. Detectable in AMIGA and HEAT denser sub-array in AUGER. Within a few years.
UHECR may be either nucleons or nuclei; in the latter case the Lightest Nuclei, as He, Li, Be, explains at best the absence of Virgo signals and the crowding of events around Cen-A bent by galactic magnetic fields. This model fit the observed nuclear mass composition discovered in AUGER. However UHECR nucleons above GZK produce EeV neutrinos while Heavy Nuclei, as Fe UHECR do not produce much. UHECR He nuclei at few tens EeV suffer nuclear fragmentation (producing low energetic neutrino at tens PeVs) but it suffer anyway photo-pion GZK suppression (leading to EeV neutrinos) once above one-few 10^{20} eV. Both these cosmogenic UHE secondary neutrinos signals may influence usual predicted GZK Tau Neutrino Astronomy in significant and detectable way; the role of resonant antineutrino electron-electron leading to Tau air-shower may also rise.
This Conference is the fifth of a series of Workshops on High Energy Gamma- ray Experiments, following the Conferences held in Perugia 2003, Bari 2004, Cividale del Friuli 2005, Elba Island 2006. This year the focus was on the use of gamma-ray to stu dy the Dark Matter component of the Universe, the origin and propagation of Cosmic Rays, Extra Large Spatial Dimensions and Tests of Lorentz Invariance.
Electron neutrino has been the first neutral lepton to be foreseen and discovered last century. The un-ordered muon and its neutrino arose later by cosmic rays. The tau discover, the heaviest, the most unstable charged lepton, was found surprisingly on 1975. Its neutrino was hardly revealed just on 2000. So why High Energy Neutrino Astronomy should rise first via tau neutrino, the last, the most rare one? The reasons are based on a chain of three favorable coincidences found last decade: the neutrino masses and their flavor mixing, the UHECR opacity on Cosmic Black Body (GZK cut off on BBR), the amplified tau air-shower decaying in flight. Indeed guaranteed UHE GZK tau neutrinos, feed by muon mixing, while skimming the Earth might lead to boosted UHE tau, mostly horizontal ones. These UHE lepton decay in flight are spread, amplified, noise free Air-Shower: a huge event for an unique particle. To be observed soon: within Auger sky, in present decade. Its discover may sign of the first tau appearance.
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