scholarly journals Lepton Pair Čerenkov Radiation Emitted by Tachyonic Neutrinos: Lorentz-Covariant Approach and IceCube Data

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Ulrich D. Jentschura ◽  
Robert Ehrlich
Keyword(s):  
Dispersion Relation ◽  
Energy Loss ◽  
Neutrino Mass ◽  
Decay Channel ◽  
Mass Term ◽  
Lepton Pair ◽  
Cerenkov Radiation ◽  
Covariant Approach ◽  
Neutrino Spectrum ◽  
Potential Onset

Current experiments do not exclude the possibility that one or more neutrinos are very slightly superluminal or that they have a very small tachyonic mass. Important bounds on the size of a hypothetical tachyonic neutrino mass term are set by lepton pair Čerenkov radiation (LPCR), that is, by the decay channelν→e+e-ν, which proceeds via a virtualZ0boson. Here, we use a Lorentz-invariant dispersion relation which leads to very tight constraints on the tachyonic mass of neutrinos; we also calculate decay and energy loss rates. A possible cutoff seen in the IceCube neutrino spectrum forEν>2 PeV, due to the potential onset of LPCR, is discussed.

scholarly journals Neutrino Pair Cerenkov Radiation for Tachyonic Neutrinos

2017 ◽  
Vol 2017 ◽  
pp. 1-8
Author(s):  
Ulrich D. Jentschura ◽  
István Nándori
Keyword(s):  
Dispersion Relation ◽  
Energy Loss ◽  
Loss Rate ◽  
Lepton Pair ◽  
Cerenkov Radiation ◽  
Medium Energy ◽  
Loss Mechanism ◽  
Additional Energy ◽  
Energy Domain ◽  
Neutrino Pair

The emission of a charged light lepton pair by a superluminal neutrino has been identified as a major factor in the energy loss of highly energetic neutrinos. The observation of PeV neutrinos by IceCube implies their stability against lepton pair Cerenkov radiation. Under the assumption of a Lorentz-violating dispersion relation for highly energetic superluminal neutrinos, one may thus constrain the Lorentz-violating parameters. A kinematically different situation arises when one assumes a Lorentz-covariant, space-like dispersion relation for hypothetical tachyonic neutrinos, as an alternative to Lorentz-violating theories. We here discuss a hitherto neglected decay process, where a highly energetic tachyonic neutrino may emit other (space-like, tachyonic) neutrino pairs. We find that the space-like dispersion relation implies the absence of a q2 threshold for the production of a tachyonic neutrino-antineutrino pair, thus leading to the dominant additional energy loss mechanism for an oncoming tachyonic neutrino in the medium-energy domain. Surprisingly, the small absolute values of the decay rate and energy loss rate in the tachyonic model imply that these models, in contrast to the Lorentz-violating theories, are not pressured by the cosmic PeV neutrinos registered by the IceCube collaboration.

The effect of boundaries on wave propagation in a liquid-filled porous solid: VI. Love waves in a double surface layer

1964 ◽  
Vol 54 (1) ◽  
pp. 417-423
Author(s):  
H. Deresiewicz
Keyword(s):  
Wave Propagation ◽  
Surface Layer ◽  
Dispersion Relation ◽  
Energy Loss ◽  
Classical Solution ◽  
Specific Energy ◽  
Classical Case ◽  
Specific Energy Loss ◽  
Double Surface ◽  
The One

abstract The classical solution of Stoneley and Tillotson is generalized by considering the outer one of the pair of layers to be porous. Although the dispersion relation turns out, for practical purposes, to be identical with the one governing the classical case, the motion in the present instance is shown to be dissipative and the expression is exhibited for the specific energy loss.

A THEORETICAL PATTERN FOR NEUTRINO AND STERILE-NEUTRINO OSCILLATIONS

1989 ◽  
Vol 04 (06) ◽  
pp. 535-541
Author(s):  
JIANG LIU
Keyword(s):  
Neutrino Mass ◽  
Neutrino Oscillations ◽  
Sterile Neutrino ◽  
Mass Term ◽  
Grand Unification ◽  
Heavy Neutrino ◽  
Theoretical Pattern

A theoretical pattern for the MSW oscillation that takes νeL into a sterile particle is discussed. The required small neutrino mass is induced by a seesaw formula, in which the heavy neutrino mass term is of the order of the grand unification scale. Realizations of our scheme are illustrated by a simple SU (2)L × U (1)Y model.

scholarly journals SINGLE MASSLESS MAJORANA FERMION IN THE DOMAIN-WALL FORMALISM

1998 ◽  
Vol 13 (20) ◽  
pp. 1667-1674 ◽  
Author(s):  
TOMOHIRO HOTTA ◽  
TAKU IZUBUCHI ◽  
JUN NISHIMURA
Keyword(s):  
Dispersion Relation ◽  
Domain Wall ◽  
Zero Mode ◽  
Mass Term ◽  
Fine Tuning ◽  
Majorana Fermion ◽  
Seesaw Mechanism ◽  
Yang Mills ◽  
Majorana Mass ◽  
Lattice Construction

We study the domain-wall formalism with additional Majorana mass term for the unwanted zero-mode, which has recently been proposed for lattice construction of 4D [Formula: see text] super-Yang–Mills theory without fine-tuning. Switching off the gauge field, we study the dispersion relation of the energy eigenstates numerically, and find that the method works for reasonable values of Majorana mass. We point out, however, that when the Majorana mass is too large, a problem arises which can be explained in terms of seesaw mechanism.

scholarly journals Precision measurement of the electron energy-loss function in tritium and deuterium gas for the KATRIN experiment

2021 ◽  
Vol 81 (7) ◽  
Author(s):  
M. Aker ◽  
A. Beglarian ◽  
J. Behrens ◽  
A. Berlev ◽  
U. Besserer ◽  
...  
Keyword(s):  
Energy Loss ◽  
Neutrino Mass ◽  
Loss Function ◽  
Precision Measurement ◽  
Measurement Data ◽  
Gas Mixture ◽  
Systematic Effect ◽  
Effective Electron ◽  
Energy Loss Function ◽  
Katrin Experiment

AbstractThe KATRIN experiment is designed for a direct and model-independent determination of the effective electron anti-neutrino mass via a high-precision measurement of the tritium $$\upbeta $$ β -decay endpoint region with a sensitivity on $$m_\nu $$ m ν of 0.2 $$\hbox {eV}/\hbox {c}^2$$ eV / c 2 (90% CL). For this purpose, the $$\upbeta $$ β -electrons from a high-luminosity windowless gaseous tritium source traversing an electrostatic retarding spectrometer are counted to obtain an integral spectrum around the endpoint energy of 18.6 keV. A dominant systematic effect of the response of the experimental setup is the energy loss of $$\upbeta $$ β -electrons from elastic and inelastic scattering off tritium molecules within the source. We determined the energy-loss function in-situ with a pulsed angular-selective and monoenergetic photoelectron source at various tritium-source densities. The data was recorded in integral and differential modes; the latter was achieved by using a novel time-of-flight technique. We developed a semi-empirical parametrization for the energy-loss function for the scattering of 18.6-keV electrons from hydrogen isotopologs. This model was fit to measurement data with a 95% $$\hbox {T}_2$$ T 2 gas mixture at 30 K, as used in the first KATRIN neutrino-mass analyses, as well as a $$\hbox {D}_2$$ D 2 gas mixture of 96% purity used in KATRIN commissioning runs. The achieved precision on the energy-loss function has abated the corresponding uncertainty of $$\sigma (m_\nu ^2)< {{10}^{-2}}{\hbox {eV}^{2}}$$ σ ( m ν 2 ) < 10 - 2 eV 2 [1] in the KATRIN neutrino-mass measurement to a subdominant level.

An Analysis of Wave Propagation in Bubbly Two-Component, Two-Phase Flow

1985 ◽  
Vol 107 (2) ◽  
pp. 402-408 ◽  
Author(s):  
L. Y. Cheng ◽  
D. A. Drew ◽  
R. T. Lahey
Keyword(s):  
Wave Propagation ◽  
Dispersion Relation ◽  
Two Phase Flow ◽  
Wave Attenuation ◽  
Bubbly Flow ◽  
Mass Term ◽  
Resonance Phenomenon ◽  
Phase Flow ◽  
Two Phase ◽  
Two Component

Wave propagation in bubbly two-phase, two-component flow was analyzed to assess the validity of some interfacial transfer laws for two-fluid models of two-phase flow. A dispersion relation was derived from the linearized conservation equations and the Rayleigh equation. The phase velocity and wave attenuation calculated from the dispersion relation, compared well with existing high- and low-frequency data. The virtual mass term was found to have a significant effect on wave dispersion in the bubbly flow regime. Thermal effects were found to be important in determining the resonance phenomenon and wave scattering was a major source of damping at frequencies higher than the resonance frequency.

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