Related papers: Z-lineshape versus 4th generation masses

We consider implications of a fourth generation of leptons, allowing for the most general mass patterns for the fourth generation neutrino. We determine the constraints due to the precision electroweak measurements and outline the…

We construct a model that allows us to determine the three neutrino masses directly from the experimental mass squared differences, $\Delta_{\rm atm}$ and $\Delta_{\rm sol}$, together with the assumption that $\Lambda = \surd (1/6) = \surd…

Massive neutrinos have a detectable effect on cosmological structure formation, in particular on the large-scale distribution of galaxies. Adding Hot Dark Matter to the now-standard Lambda CDM model leads to a worse fit to large-scale…

An alternative to the famous see-saw mechanism is proposed to explain the smallness of the neutrino masses (if present). This model involves a fourth family which mixes very little with the other three. It contains one heavy neutrino (mN >…

This is the fourth of a series of papers in which we derive simultaneous constraints on cosmological parameters and X-ray scaling relations using observations of the growth of massive, X-ray flux-selected galaxy clusters. Here we examine…

The interplay between neutrino masses and the interactions of neutrinos with matter is discussed with an eye to extending the latter to include possible new interactions. This conjecture may resolve the conundrum posed by the present…

We explore an extension of the fourth generation model with multi-Higgs doublets and three fermion singlets. The Standard Model neutrinos acquire mass radiatively at one loop level while the fourth generation neutrinos acquire a heavy…

We propose signals in the cosmic microwave background to probe the type and spectrum of neutrino masses. In theories that have spontaneous breaking of approximate lepton flavor symmetries at or below the weak scale, light pseudo-Goldstone…

This is a report on the status and prospects of the quantification of neutrino properties through the cosmological neutrino background for the Cosmic Frontier of the Division of Particles and Fields Community Summer Study long-term planning…

All existing data on neutrino oscillations (including those from the LSND experiment) imply a four neutrino scheme with six different allowed mass patterns. Some of the latter are shown to be disfavored by using a conservative upper bound…

By combining data from cosmic microwave background (CMB) experiments (including the recent WMAP third year results), large scale structure (LSS) and Lyman-alpha forest observations, we constrain the hypothesis of a fourth, sterile, massive…

For Majorana or Dirac neutrinos, using Fritzsch-like texture 4 zero mass matrices with parallel texture structures for the charged leptons and the Dirac neutrino mass matrix (M_{\nu D}), detailed predictions for cases pertaining to…

We discuss a neutrino mass model based on the S4 discrete symmetry where the symmetry breaking is triggered by the boundary conditions of the bulk right-handed neutrino in the fifth spacial dimension. While the symmetry restricts bare mass…

Constraints on neutrino masses are estimated based on future observations of the cosmic microwave background (CMB), which includes the B-mode polarization produced by CMB lensing from the Planck satellite, and the growth rate of cosmic…

We analyze the capacity of future $Z$-factories to search for heavy neutrinos with their mass from 10 to 85 GeV. The heavy neutrinos $N$ are considered to be produced via the process $e^+e^-\to Z\to \nu N$ and to decay into an electron or…

We investigate the nucleosynthesis constraint on Lorentz invariance violation in the neutrino sector which influences the formation of light elements by altering the energy density of the Universe and weak reaction rates prior to and during…

Models of dark energy in which neutrinos interact with the scalar field supposed to be responsible for the acceleration of the universe usually imply a variation of the neutrino masses on cosmological time scales. In this work we propose a…

I discuss dynamical generation of neutrino masses in unconventional scenarios where the background space-time geometry plays a crucial role. I discuss two types of backgrounds: (i) Lorentz Violating and (ii) Geometries with Torsion. In the…

Heavy fourth generation Majorana neutrino can be stable and contribute to a small fraction of the relic density of dark matter (DM) in the Universe. Due to its strong coupling to the standard model particles, it can be probed by the current…

We study the constraints which the next generation of radio telescopes could place on the mass and number of neutrino species by studying the gravitational lensing of high redshift 21 cm emission in combination with wide-angle surveys of…