Search results for "sterile"
showing 4 items of 164 documents
Search for sterile neutrinos in the CC verbatim_mark>mathend000# mode at the new CERN-SBLNF
2013
The possible existence of non-active neutrinos for the ElectroWeak interactions was first proposed in 1967 by B. Pontecorvo who named them "sterile" neutrinos. Recent tensions among world-wide experimental data renewed the possibility of one or more sterile neutrino states. Several "anomalies" emerged in radioactive sources and reactor neutrino experiments, as well as the long-standing LSND and the recent MiniBooNE hints for neutrino and antineutrino oscillations with a δm2 at the eV2 scale, not compatible with the standard 3 × 3 neutrino mixing scenario. While a huge effort is being devoted to establish the standard three-neutrino mixing paradigm no conclusive experiment was carried out to…
Self-interacting dark matter and cosmology of a light scalar mediator
2015
We consider a fermionic dark matter candidate interacting via a scalar mediator coupled with the Standard Model through a Higgs portal. We consider general setting including both scalar and pseudoscalar interactions between the scalar and fermion, and illustrate the relevant features for dark matter abundance, direct search limits and collider constraints. The case where dark matter has a self-interaction strength $\left\langle \sigma_V \right\rangle/m_\psi \sim 0.1-1 \,\mathrm{cm}^2/\mathrm{g}$ is strongly constrained, in particular by the Big Bang Nucleosynthesis. We show that these constraints can be alleviated by introducing a new light sterile neutrino $N$. The allowed region for the e…
Phenomenology of low-scale Seesaw Models
2016
All the observed particles are well accommodated in the Standard Model, together with the basic forces. However, there are both experimental and theoretical hints that the Standard Model can not be a complete theory and that New Physics is needed. Some of the theoretical problems are: i) The flavor-puzzle, i.e., why are there three copies of particles differing only by their mass. Most of the free parameters in the Standard Model are linked to this puzzle. They have been measured, but their values do not follow any clear pattern and their origin remains elusive. ii) The strong CP problem, that is, why the CP symmetry is conserved in the strong interactions in the Standard Model, which is no…