We present the analytical solution of a maser shaped like a spherical shell. We determine the general condition on the size of the central cavity at which a sphere becomes a shell maser, and derive the intensity, beaming angle and observed size of both unsaturated and saturated shells.

The spectral statistics of low–lying states of several f p shell nuclei are studied with realistic shell–model calculations. For Ca isotopes, we find significant deviations from the predictions of the random–matrix theory which suggest that some spherical nuclei are not as chaotic in nature as the conventional view assumes.

A set of vectors all of which have a constant (non-zero) norm value in a Euclidean lattice is called a shell of the lattice. Venkov classified strongly perfect lattices of minimum 3 (Rèseuaux et “designs” sphérique, 2001), whose minimal shell is a spherical 5-design. This note considers the classification of integral lattices whose shells of norm 3 are 5-designs.

Calcium carbonate (CaCO3) in the presence of single-walled carbon nanotube (SWCNT) /fullerodendron supramolecular nanocomposites was crystallized with a CO2 diffusion method under ambient conditions and in aqueous environments to produce monodisperse spherical SWCNT/CaCO3 hybrids with a core-shell structure. The crystals nucleate at the carboxyl groups on the surface of the SWCNT/fullerodendron...

We study axisymmetric mean field spherical and spherical shell dynamo models, with both dynamic and algebraic α-quenchings. Our results show that there are qualitative as well as quantitative differences and similarities between these models. Regarding similarities, both groups of models exhibit symmetric, antisymmetric and mixed modes of behaviour. As regards differences, the important feature...

We show that the icosahedral packings of protein capsomeres proposed by Caspar and Klug for spherical viruses become unstable to faceting for sufficiently large virus size, in analogy with the buckling instability of disclinations in two-dimensional crystals. Our model, based on the nonlinear physics of thin elastic shells, produces excellent one-parameter fits in real space to the full three-d...

Four 16 cm diameter spherical phantoms were modeled in this study: a homogenous water phantom, and three water phantoms with 1 cm thick shell each made of different materials (PMMA, Plastic WaterTM and polystyrene). The PENELOPE Monte Carlo code was utilized to simulate photon beams from the Leksell Gamma Knife (LGK) unit and to determine absorbed dose to water (Dw) from a single 18 mm beam del...

The shell structure of magic nuclei far from stability is discussed in terms of the self-consistent spherical Hartree-Fock-Bogoliubov theory. In particular, the sensitivity of the shell-gap sizes and the two-neutron separation energies to the choice of particle-hole and particle-particle components of the effective interaction is investigated.

The spectral statistics of low–lying states of f p shell nuclei are studied by performing large shell–model calculations with a realistic nuclear interaction. For Ca isotopes, we find deviations from the predictions of the random–matrix theory which suggest that some spherical nuclei are not as chaotic in nature as the conventional view assumes.