Home OALib Journal OALib PrePrints Submit Ranking News My Lib FAQ About Us Follow Us+
 Title Keywords Abstract Author All
Search Results: 1 - 10 of 100 matches for " "
 Page 1 /100 Display every page 5 10 20 Item
 Natural Science (NS) , 2011, DOI: 10.4236/ns.2011.32020 Abstract: This paper presents theoretical investigation on explanation of the mass defect estimating a new value for the proton mass inside the nucleus in the presence of the gravitational potential, the work has been done by using a new theory called the generalized special relativity (GSR).
 Physics , 1996, DOI: 10.1103/PhysRevD.54.4356 Abstract: It has been noted for a long time that, in some circumstances, {\sl massless} neutrinos may be {\sl mixed} in the leptonic charged current. Conventional neutrino oscillation searches in vacuum are insensitive to this mixing. We discuss the effects of resonant massless-neutrino conversions in the dense medium of a supernova. In particular, we show how the detected $\bar\nu_e$ energy spectra from SN1987a and the supernova $r$-process nucleosynthesis may be used to provide very stringent constraints on the mixing of {\sl massless} neutrinos.
 Jorge S. Diaz Physics , 2014, DOI: 10.1155/2014/962410 Abstract: Neutrinos can be used to search for deviations from exact Lorentz invariance. The worldwide experimental program in neutrino physics makes these particles a remarkable tool to search for a variety of signals that could reveal minute relativity violations. This paper reviews the generic experimental signatures of the breakdown of Lorentz symmetry in the neutrino sector.
 High Energy Physics - Phenomenology , 2008, DOI: 10.1142/S0217732309031855 Abstract: The unknown neutrino parameters may leave detectable signatures in the supernova (SN) neutrino flux. However, even the contribution from the MSW flavor transition alone could cause ambiguity in the interpretation to the neutrino signals because of the uncertain local density profile of the SN matter and the model-dependent SN neutrino spectral parameters. A specific parametrization to the unknown local density profile is proposed in this work, and the contribution from the standard MSW effect is investigated through a multi-detector analysis of the SN neutrinos. In establishing the model-independent scheme, results based on the existing spectral models are included. The limitation of the analysis is also discussed.
 Physics , 2009, DOI: 10.1007/JHEP03(2010)031 Abstract: High energy cosmic neutrino fluxes can be produced inside relativistic jets under the envelopes of collapsing stars. In the energy range E ~ (0.3 - 1e5) GeV, flavor conversion of these neutrinos is modified by various matter effects inside the star and the Earth. We present a comprehensive (both analytic and numerical) description of the flavor conversion of these neutrinos which includes: (i) oscillations inside jets, (ii) flavor-to-mass state transitions in an envelope, (iii) loss of coherence on the way to observer, and (iv) oscillations of the mass states inside the Earth. We show that conversion has several new features which are not realized in other objects, in particular interference effects ("L- and H- wiggles") induced by the adiabaticity violation. The neutrino-neutrino scattering inside jet and inelastic neutrino interactions in the envelope may produce some additional features at E > 1e4 GeV. We study dependence of the probabilities and flavor ratios in the matter-affected region on angles theta13 and theta23, on the CP-phase delta, as well as on the initial flavor content and density profile of the star. We show that measurements of the energy dependence of the flavor ratios will, in principle, allow to determine independently the neutrino and astrophysical parameters.
 Physics , 1999, DOI: 10.1016/S0370-2693(99)00487-6 Abstract: Neutrino oscillations with parameters relevant for the large mixing solution of the solar neutrino problem ($\Delta m^2_{21} = (2 - 20) \cdot 10^{-5}$ eV$^2$, $\sin^2 2\theta_{12} > 0.65$) can lead to observable (up to 10 - 12 %) excess of the e-like events in the sub-GeV atmospheric neutrino sample. The excess has a weak zenith angle dependence in the low energy part of the sample and strong zenith angle dependence in the high energy part. The effect rapidly decreases with energy of neutrinos, it is suppressed in the multi-GeV sample. These signatures allow to disentangle the effect from other possible explanations of the excess. The possibility of change of the sign of the up-down asymmetry of the excess with energy (positive in the sub-GeV region and negative in the multi-GeV region) is marked. The predicted properties of excess are in agreement with SuperKamiokande data.
 Sean Grullon Physics , 2010, Abstract: The IceCube Neutrino Observatory is a 1 $km^{3}$ detector currently under construction at the South Pole. Searching for high energy neutrinos from unresolved astrophysical sources is one of the main analysis strategies used in the search for astrophysical neutrinos with the IceCube Neutrino Observatory. A hard energy spectrum of neutrinos from isotropically distributed astrophysical sources could contribute to form a detectable signal above the atmospheric neutrino background. A reliable method of estimating the energy of the neutrino-induced lepton is crucial for identifying astrophysical neutrinos. An analysis is underway using data from the half completed detector taken during its 2008-2009 science run.
 Indranath Bhattacharyya Physics , 2013, Abstract: The study of supernova neutrinos result an interesting non-linear phenomenon, consisting of three phases: synchronized oscillation phase, bipolar flavor conversion phase and the phase of spectral split. In the collective oscillation of supernova neutrino the self energy is not a constant but varies adiabatically, which is responsible to have such different phases. In this article the transition point from synchronized oscillation to bipolar phase is studied numerically as well as analytically. The numerical results yielding different graphs depending on different values of possible small but non-vanishing mixing angles show the onset of the bipolar phase from the synchronized phase varies as the mixing angle. But the analytical study in terms of a spinning top model results a unique onset condition, which is independent of the choice of mixing angle. Such discrepancy between numerical results and analytical results is explained properly.
 Physics , 1999, Abstract: UHE neutrinos may transfer highest cosmic-rays energies overcoming $2.75K^\circ$ BBR and radio-waves opacities (the GZK cut off) from most distant AGN sources at the age of the Universe. These UHE $\nu$ might scatter onto those (light and cosmological) relic neutrinos clustered around our galactic halo or nearby neutrino hot dark halo clustered around the AGN blazar and its jets. The branched chain reactions from a primordial nucleon (via photo production of pions and decay to UHE neutrinos) toward the consequent beam dump scattering on galactic relic neutrinos is at least three order of magnitude more efficient than any known neutrino interactions with Earth atmosphere or direct nucleon propagation. Therefore the rarest cosmic rays (as the 320 EeV event) might be originated at far $(\tilde{>} 100 Mpc)$ distances (as Seyfert galaxy MCG 8-11-11); its corresponding UHE radiation power is in agreement with the observed one in MeV gamma energies. The final chain products observed on Earth by the Fly's Eye and AGASA detectors might be mainly neutron and anti-neutrons and delayed, protons and anti-protons at symmetric off-axis angles. These hadronic products are most probably secondaries of $W^+ W^-$ or $ZZ$ pair productions and might be consistent with the last AGASA discoveries of doublets and one triplet event.
 Rafael Torrealba Physics , 2011, Abstract: The OPERA experiment has reported neutrinos, from the CNGS beam, that arrived to Gran Sasso Laboratory 60ns earlier that expected for light, within a statistical error margin of {\S}6:9 and a systemic error of {\S}7:4. Therefore, these neutrinos are faster than known velocity of the light in vacuum. These puzzling result could be explained by stimulated emission of neutrinos in the decay tunnel, in close analogy with the amplification of a LASER pulse.
 Page 1 /100 Display every page 5 10 20 Item