80,332 research outputs found
Success Stories in Asian Aquaculture
The stories presented in this book reflect the unique nature of Asian aquaculture, providing first-time insight into how and why it has become so successful. Overall, the book demonstrates how the resiliency, adaptability, and innovation of small-scale aquaculture farmers have been crucial to this success. It also places aquaculture development in Asia into a wider global context, and describes its relationship to natural systems, social conditions, and economics. The book is unique in its in-depth presentation of primary research on Asian aquaculture, and in demonstrating how aquaculture can have a lasting positive impact on livelihoods, food security, and sustainable development
Sterile neutrino dark matter, CDMS-II and a light Higgs boson
We add a singlet right handed neutrino plus a charged and a neutral singlet
scalars to the standard model. This extension includes a discrete symmetry such
that we obtain a heavy sterile neutrino which couples only to the electron and
the new scalars. In this sense the singlet neutrino does not mix with ordinary
ones and thus has no effect on Big Bang Nucleosynthesis. However, such sterile
neutrino can be in equilibrium with electroweak particles in the early Universe
due to its couplings to electrons and also because the Higgs boson mixes with
the singlet scalars. We obtain that the sterile neutrino constitutes a dark
matter candidate and analyze its direct detection in the light of current
experiments. Our results show that if such a sterile neutrino is realized in
nature, and CDMS-II experiment confirms its positive signal, dark matter
demands a rather light Higgs boson with new Physics at some 500 GeV scale.Comment: 16 pages, 13 figures, uses axodraw.st
Spontaneous CP violation in the 3-3-1 model with right-handed neutrinos
We implement the mechanism of spontaneous CP violation in the 3-3-1 model
with right-handed neutrinos and recognize their sources of CP violation. Our
main result is that the mechanism works already in the minimal version of the
model and new sources of CP violation emerges as an effect of new physics at
energies higher than the electroweak scale.Comment: Major changes in the quark sector, electronic dipole moment of the
neutron was evaluated, accepted for publication in the physical review
Regular black holes in gravity
In this work, we study the possibility of generalizing solutions of regular
black holes with an electric charge, constructed in general relativity, for the
theory, where is the Gauss-Bonnet invariant. This type of solution
arises due to the coupling between gravitational theory and nonlinear
electrodynamics. We construct the formalism in terms of a mass function and it
results in different gravitational and electromagnetic theories for which mass
function. The electric field of these solutions are always regular and the
strong energy condition is violated in some region inside the event horizon.
For some solutions, we get an analytical form for the function. Imposing
the limit of some constant going to zero in the function we recovered
the linear case, making the general relativity a particular case.Comment: 22 pages, 25 figures.Version published in EPJ
Majorana Dark Matter in Minimal Higgs Portal Models after LUX
We consider the Singlet Majorana fermion dark matter model, in which the
standard model particles interact with the dark sector through the mixing of a
singlet scalar and the Higgs boson. In this model both the dark matter and the
singlet scalar carry lepton number, the latter being a bilepton. We suppose the
existence of a symmetry, remnant of some high energy local symmetry
breaking, that stabilizes the Majorana fermion. We analyzed the parameter space
of this model and found that the lepton number symmetry breaking scale, drove
by the singlet scalar, is constrained to be within hundreds to thousands of
GeV, so as to conform with the observed dark matter relic density. Finally, we
address the direct detection and invisible Higgs decay complementarity,
confronting our model with recent LUX and LHC constraints, as well as XENON1T
prospects.Comment: 20 pages, 12 figure
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