41,003 research outputs found
Mass dimension one fermions from flag dipole spinors
According to the Lounesto classification, there are six classes of spinors.
The Dirac and Weyl spinors belong to the first three and the sixth classes
respectively. The remaining fourth and fifth classes are known as the flag
dipole and flag pole spinors respectively. In this letter, a mass dimension one
fermionic field with flag dipole spinors as expansion coefficients is
constructed. These spinors are shown to be related to Elko (flag pole spinors)
by a matrix transformation. It shows that the flag dipole spinors are
generalizations of Elko. To construct a Lorentz-covariant quantum field, an
infinitesimal deformation is applied to the spinor dual. Subsequently, we show
that the fermionic fields constructed from Elko and flag dipole spinors are
physically equivalent.Comment: 10 page
Penguin-induced Radiative Baryonic B Decays Revisited
Weak radiative baryonic B decays mediated by
the electromagnetic penguin process are re-examined within the
framework of the pole model. The meson pole contribution that has been
neglected before is taken into account in this work. It is found that the
intermediate contribution dominates in the mode and
is comparable to the baryon pole effect in and
modes. The branching ratios for and are of order
and , respectively. The threshold enhancement effect in the
dibaryon mass spectrum is responsible by the meson pole diagram. We also study
the angular distribution of the baryon in the dibaryon rest frame. The baryon
pole diagrams imply that the antibaryon tends to emerge in the direction of the
photon in the baryon-pair rest frame. The predicted angular asymmetry agrees
with experiment for . Measurements of the
correlation of the photon with the baryon allow us to discriminate between
different models for describing the radiative baryonic B decays. For decays
, a large correlation of the photon to the
and a broad bump in the dibaryon mass spectrum are predicted.Comment: 10 pages, 4 figure
Magnetic field creation by solar mass neutrino jets
Parity violation and its effects for neutrinos in astrophysical contexts have
been considered earlier in pioneering papers of Hawking and Vilenkin. But
because even the largest magnetic moments predicted by physics beyond the
Standard Model are some twelve orders of magnitude smaller than the Bohr
magneton, their implications for magnetic field generation and neutrino
oscillations are generally considered insignificant. Here we show that since in
astrophysical scenarios a huge number of neutrinos may be emitted, the
smallness of the magnetic moment, when coupled with parity violation, is
compensated by the sheer number of neutrinos. The merger of neutron stars would
leave behind a short pulse of electromagnetic synchrotron radiation even if the
neutrino jet in the merger points away from the neutrino detectors. We show
that the magnetic field can be as large as 10^6\,\mbox{Gauss} and comment on
the possibility of direct detection. Observation of such a pulse would lend
strong support for neutrino magnetic moments and resolve the missing neutrino
problem in neutron star mergers.Comment: 5 pages, version accepted for publication in Europhysics Letters
(EPL
A QFT-induced phase in neutrino flavour oscillations
In the extended Standard Model of particle physics, each neutrino mass
eigenstate is predicted to have a tiny but non vanishing magnetic moment
induced by quantum field theoretic corrections. These QFT-induced magnetic
momenta depend linearly on masses of the underlying mass eigenstates with a
proportionality constant . As a consequence
when neutrinos are embedded in an environment containing magnetic fields the
flavour oscillations get a contribution from the induced relative phases.Comment: 6 page
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