SLIM at LHC: LHC search power for a model linking dark matter and neutrino mass

Recently a model has been proposed that links dark matter and neutrino masses. The dark matter candidate which is dubbed as SLIM has a mass of MeV scale and can show up at low energy experiments. The model also has a high energy sector which consists of a scalar doublet, $(\phi^-, \phi^0)$. We discuss the potential of the LHC for discovering the new scalars. We focus on the $\phi^+\phi^-$ and $\phi^{\pm} \phi^0$ production and the subsequent decay of the charged scalar to a charged lepton and the SLIM which appears as missing energy. Identifying the background, we estimate the signal significance and find that it can exceed $5 \sigma$ at 30 ${\rm fb}^{-1}$ for the 14 TeV run at the LHC. We comment on the possibility of extracting the flavor structure of the Yukawa couplings which also determine the neutrino mass matrix. Finally, we discuss the prospects of this search at the current 7 TeV run of the LHC.Comment: 26 pages, 21 figure

Activating the 4th Neutrino of the 3+1 Scheme

Non-Standard Interactions (NSI) of neutrinos with matter has received renewed interest in recent years. In particular, it has been shown that NSI can reconcile the $3+1$ solution with IceCube atmospheric data with $E_\nu >500$ GeV, provided that the effective coupling of NSI is large, e.g. $\sim 6 G_F$. The main goal of the present paper is to show that contrary to intuition, it is possible to build viable models with large NSI by invoking a new $U(1)$ gauge symmetry with gauge boson of mass $\sim 10$ eV. We refer to these new constructions as $3+1+ U(1)$ models. In the framework of a $3+1$ solution to LSND and MiniBooNE anomalies, we show that this novel NSI can help to solve the tension with cosmological bounds and constraints from IceCube atmospheric data with $E_\nu>500$ GeV. We then discuss the implications of the MINOS and MINOS+ results for the 3+1+$U(1)$ scenario.Comment: 24 pages, 5 figure

Dirac neutrino mass generation from dark matter

In 2006, a simple extension of the Standard Model was proposed in which neutrinos obtain radiative Majorana masses at one-loop level from their couplings with dark matter, hence the term "scotogenic," from the Greek "scotos" meaning darkness. Here an analogous mechanism for Dirac neutrino masses is discussed in a minimal model. In different ranges of the parameter space, various candidates for dark matter are possible. In particular, the lightest Dirac fermion which appears in the loop diagram generating neutrino mass can be a viable dark matter candidate. Such a possibility does not exist for the Majorana case. Realistic neutrino mixing in the context of $A_4$ is discussed. A possible supersymmetric extension is also briefly discussed.Comment: 17 pages, 2 figures; v3: version to appear in PR

Mapping complexity sources in nuclear power plant domains

Understanding the sources of complexity in advanced Nuclear Power Plant (NPP) control rooms and their effects on human reliability is critical for ensuring safe performance of both operators and the entire system. New generation control rooms will rely more heavily on automation and computerized Human-System Interfaces (HSI). Without proper management, information representation and required operator-system interaction could challenge operator information processing capabilities. This paper provides an initial step in assessing the sources of complexity in the NPP control rooms and introduces a systems-theoretic descriptive model of these sources of complexity leveraging network theory.U.S. Nuclear Regulatory Commissio