The new cicada genus Inflatopyga and six new species of this genus are described from the Solomon Islands. The genus belongs to the subtribe Cosmopsaltriaria of the tribe Dundubiini (family Cicadidae). The species are mainly island endemics. Inflatopyga boulardi, sp. nov., I. ewarti, sp. nov., and I. verlaani, sp. nov., are endemic to Bougainville, I. langeraki, sp. nov. (type species), is endemic to Guadalcanal and New Georgia, I. webbi, sp. nov., to Santa Isabel and I. mouldsi, sp. nov., to Malaita. A key to the males is provided. Inflatopyga is the sister-genus of Rhadinopyga, while both genera together are considered to be the sister-group of Diceropyga. A cladogram showing the apomorphies suggests the monophyletic origin of the genera and the genus relationships. The biogeography of the cicadas of the Solomon Islands is discussed. The distribution and monophyly of Inflatopyga suggest that the Solomon Islands form an area of endemism.
Neutron diffraction results on single crystals of CsCuCl3 in high magnetic fields are reported. The fields were applied parallel (up to about 6.5 T) and perpendicular (up to 8.5 T) to the c axis of the hexagonal crystal. For the parallel field a spin-flop-like change in the magnetic structure at fields above 5.6 T was observed close below the Neel temperature. The magnetic phase diagram has been determined in the temperature range between 9.6 K and TN=10.675 K. In the perpendicular field the magnetic satellite reflections, originating from the helical magnetic spin structure of the Cu ions, shift their positions in rising field, indicating a stretching out of the helices. The results are interpreted in the light of recent theoretical predictions about the transitions being triggered by quantum or thermal fluctuations. In addition to determining the spin structures, we find that the critical exponent beta is close to 0.25 in the low-field phase and probably close to 0.125 in the high-field phase.
Inelastic neutron scattering measurements were performed on the ferromagnetic chain system CsNiF 3 in the collinear antiferromagnetic ordered state below T N = 2.67 K. The measured spin wave dispersion was found to be in good agreement with linear spin wave theory including dipolar interactions. The additional dipole tensor in the Hamiltonian was essential to explain some striking phenomena in the measured spin wave spectrum: a peculiar feature of the dispersion relation is a jump at the zone center, caused by strong dipolar interactions in this system. The interchain exchange coupling constant and the planar anisotropy energy were determined within the present model to be J ′ /k B = −0.0247(12) K and A/k B = 3.3(1) K. This gives a ratio J/J ′ ≈ 500, using the previously determined intrachain coupling constant J/k B = 11.8 K. The small exchange energy J ′ is of the same order as the dipolar energy, which implies a strong competition between the both interactions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.