Parametrizing the Neutrino sector

The original Standard Model has massless neutrinos, but the observation of neutrino oscillations requires that neutrinos are massive. The simple extension of adding gauge singlet fermions to the particle spectrum allows normal Yukawa mass terms for neutrinos. The seesaw mechanism then suggests an explanation for the observed smallness of the neutrino masses. After reviewing the framework of the seesaw we suggest a parametrization that directly exhibits the smallness of the mass ratios in the seesaw for an arbitrary number of singlet fermions and we present our plans to perform calculations for a process that might be studied at the LHC.Comment: 8 pages; uses appolb.cls; submitted to the proceedings of "Matter to the Deepest: Recent Development in Physics of Fundamental Interactions", Ustron, Poland, 12-18 Sep 201

The Cranked Nilsson-Strutinsky versus the Spherical Shell Model: A Comparative Study of pf-Shell Nuclei

A comparative study is performed of a deformed mean field theory, represented by the cranked Nilsson-Strutinsky (CNS) model, and the spherical shell model. Energy spectra, occupation numbers, B(E2)-values, and spectroscopic quadrupole moments in the light pf shell nuclei are calculated in the two models and compared. The result is also compared to available experimental data which are generally well described by the shell model. Although the Nilsson-Strutinsky calculation does not include pairing, both the subshell occupation numbers and quadrupole properties are found to be rather similar in the two models. It is also shown that ``unpaired'' shell model calculations produce very similar energies as the CNS at all spins. The role of the pairing energy in the description of backbending and signature splitting in odd-mass nuclei is also discussed.Comment: 14 pages, 20 figures, submitted to Phys.Rev.

Progress in the parametrisation of the Neutrino sector

Adding gauge singlets to the original Standard Model allows an explanation for the observed smallness of the neutrino masses using the seesaw mechanism. Following our plans presented in the last conference of this series we present the results for the non-standard setting, when the number of the singlets is smaller than the number of the SM generations.Comment: 6 pages, 2 figures; revised version addressed the criticism of the editors, matches now the published versio

Triaxiality in 48Cr

Rotational behavior inducing triaxiality is discussed for 48Cr in the cranked Nilsson-Strutinsky (CNS) model, as well as in the spherical shell model. It is shown that the low-spin region up to about I=8, has a prolate well-deformed shape. At higher spins the shape is triaxial with a "negative-gamma" deformation, that is, with rotation around the classically forbidden intermediate axis. By comparing calculated B(E2)-values and spectroscopic quadrupole moments in the CNS with spherical shell model results and experimental data, the triaxial rotation around the intermediate axis is confirmed.Comment: 9 pages, including 6 figures; submitted to Physics Letters

Impacts of the Tropical Pacific/Indian Oceans on the Seasonal Cycle of the West African Monsoon

The current consensus is that drought has developed in the Sahel during the second half of the twentieth century as a result of remote effects of oceanic anomalies amplified by local land–atmosphere interactions. This paper focuses on the impacts of oceanic anomalies upon West African climate and specifically aims to identify those from SST anomalies in the Pacific/Indian Oceans during spring and summer seasons, when they were significant. Idealized sensitivity experiments are performed with four atmospheric general circulation models (AGCMs). The prescribed SST patterns used in the AGCMs are based on the leading mode of covariability between SST anomalies over the Pacific/Indian Oceans and summer rainfall over West Africa. The results show that such oceanic anomalies in the Pacific/Indian Ocean lead to a northward shift of an anomalous dry belt from the Gulf of Guinea to the Sahel as the season advances. In the Sahel, the magnitude of rainfall anomalies is comparable to that obtained by other authors using SST anomalies confined to the proximity of the Atlantic Ocean. The mechanism connecting the Pacific/Indian SST anomalies with West African rainfall has a strong seasonal cycle. In spring (May and June), anomalous subsidence develops over both the Maritime Continent and the equatorial Atlantic in response to the enhanced equatorial heating. Precipitation increases over continental West Africa in association with stronger zonal convergence of moisture. In addition, precipitation decreases over the Gulf of Guinea. During the monsoon peak (July and August), the SST anomalies move westward over the equatorial Pacific and the two regions where subsidence occurred earlier in the seasons merge over West Africa. The monsoon weakens and rainfall decreases over the Sahel, especially in August.Peer reviewe