Probing the Broken Symmetry with Neutrino Telescopes Zhizhong
Probing the Broken - Symmetry with Neutrino Telescopes Zhi-zhong Xing (IHEP, Beijing) NOW 2006 Z. Z. X. Phys. Rev. D 9 74 -(2006) Conca hep-ph/0605219 Specchiulla, September 16, 013009 2006
Outline 1. UHE Neutrinos: the Oscillating Messenger 2. -Telescope as a Probe of - Symmetry 3. Further Discussion and Concluding Remarks
UHE Neutrinos
High-energy Cosmic Messengers CMB Light absorbed (1 e: 1 ) Neutrino (1 e: 2 ) Proton scattered by magnetic field neutrino photon proton Ze. V Ee. V Pe. V Te. V straight-line “somebody really propagation, really wise” unabsorbed, (Tom Weiler but difficult at Neutrino to detect 2006) Log E (Ge. V) 1 2 3 large 4 neutrino 5 6 7 detector 8 9 10 12 13 telescopes a sufficiently ---11 neutrino
Optical Cherencov ANTARES La-Seyne-sur-Mer, France -Telescopes BAIKAL Russia NEMO Catania, Italy NESTOR Pylos, Greece AMANDA and Ice. Cube South Pole, Antarctica
How to identify Neutrino Flavors? Halzen, astro-ph/0602132 17 m Learned & Pakvasa 95
The Starting Point of View First of all, discover something Next, measure it precisely Point One Our concern: Initial flavor composition of UHE neutrino fluxes and their oscillations Point Two
Incomplete List of Relevant Works ■ Learned & Pakvasa, APP 3, 267 (1995) ★ Athar et al, PRD 62, 103007 (2000) ★ Bento et al, PLB 476, 205 (2000) ★ Gounaris & Moultaka, hep-ph/0212110 ★ Barenboim & Quigg, PRD 67, 073024 (2003) ★ Beacom et al, PRD 68, 093005 (2003) ★ Keraenen et al, PLB 574, 162 (2003) ★ Beacom et al, PRD 69, 017303 (2004) ★ Serpico & Kachelriess, PRL 94, 211102 (2005) ★ Bhattacharjee & Gupta, hep-ph/0501191 ★ Serpico, PRD 73, 047301 (2006) ● Xing, PRD 74, 013009 (2006) ● Xing & Zhou, PRD 74, 013010 (2006) ★ Winter, PRD 74, 033015 (2006) ■ Fogli et al, hep-ph/0608321 ★ Majumdar & Ghosal, hep-ph/0608334
UHE Neutrino Oscillations The transition probability: The expected sources (AGNs etc) at typical distances: ~100 Mpc For , the oscillation length in vacuum So after many oscillations, the averaged transition probability of UHE neutrinos is atmosphere
Data and Approximation A global analysis of current neutrino oscillation data yields at 99% C. L. (Strumia & Vissani 06) - symmetry
Broken - Symmetry
Conventional UHE Neutrino Source High-energy pp collisions: charged poins muon and electron neutrinos High-energy p collisions: There is no production of electron antineutrino, because the produced neutrons can escape the source before decaying (M. Ahlers et al, 05) In either case, the sum of neutrinos and antineutrinos
Effect of - Symmetry Breaking At the detectors of neutrino telescopes: Two small parameters to measure tiny - symmetry breaking:
Correction to the Naïve Ratio 1: 1: 1 The allowed range of : ZZX: hep-ph/0605219 The bound appears when two small - symmetry breaking parameters turn to take their maximal (upper limit) values
Signals at Neutrino Telescopes Can =0 nontrivially hold? Yes, if the following relation is by accident satisfied: A signal of 0 is in general expected, however. working observables: It makes sense The to consider the complementarity between neutrino telescopes and terrestrial neutrino oscillation experiments, in order to finally pin down the parameters of neutrino mixing and CP violation. (Winter, hep-ph/0604191)
Glashow Resonance A novel possibility to detect the UHE electron anti-neutrino flux from distant astrophysical sources (S. L. Glashow 60): A neutrino telescope may measure: (a) the GR-mediated electron anti-neutrino events; (b) the muon neutrino muon anti-neutrino charged-current interaction events in the vicinity, to extract Comment 1: it is possible to probe the - symmetry breaking; Comment 2: it is likely to probe the solar neutrino mixing angle.
Concluding Remarks
Do Flavor Physics with -Telescopes Ø The astrophysical sources of UHE neutrinos: puzzles Ø Do ultra-long baseline & ultra-high energy neutrino oscillation experiments with ultra-large -telescopes? Ø The initial flavor composition of UHE neutrino fluxes should be determined experimentally Ø Neutrino can do this, in 013010 principle Z. Z. X. & telescopes S. Zhou: Phys. Rev. D at 74 least (2006) Ø Given a well-understood source, a neutrino telescope can help determine the neutrino mixing parameters Ø There is a lot of important complementarity between terrestrial neutrino experiments & neutrino telescopes
Search for ’s at Wonderful Places South Pole Sea The Mediterranean
Last but not Least Source Detector Unless there is an exact - flavor symmetry! Thanks a lot
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