Isotopic effect in the width of a giant dipole resonance in light nuclei

An isotopic effect in the widths of giant dipole resonances is established on the basis of an analysis of the latest systematics of photoabsorption cross sections for nuclei containing 12 to 65 nucleons. This effect arises owing to isospin splitting of a giant resonance and is enhanced by its configuration splitting.     

Enhanced Physical and Mechanical Properties of Nitrile-Butadiene Rubber Composites with N-Cetylpyridinium Bromide-Carbon Black

The physical and mechanical properties of nitrile–butadiene rubber (NBR) composites with N-cetylpyridinium bromide-carbon black (CPB-CB) were investigated. Addition of 5 parts per hundred rubber (phr) of CPB-CB into NBR improved the tensile strength by 124%, vulcanization rate by 41%, shore hardness by 15%, and decreased the volumetric wear by 7% compared to those of the base rubber-CB composite.     

Isospin symmetry and giant resonance in nuclei of mass number <Emphasis Type="Italic">A</Emphasis> = 14

An analysis of the cross sections for photon absorption by isobar nuclei ¹⁴C and ¹⁴N in the giant-dipole-resonance region demonstrates a high degree of isospin symmetry for this type of collective excitations in the above nuclei. Giant resonances in A = 14 isobar nuclei are related by a simple rescaling procedure that is based on the fact that, for these nuclei, the isospin remains a good quantum number in the process of dipole excitations of energy up to about 40 MeV. The features of the isospin splitting of the giant resonance in the ¹⁴C nucleus are refined. The shape of the cross section for photoabsorption in the ¹⁴C nucleus—in particular, a large width of the giant resonance in this nucleus—is exhaustively explained.     

Ion-Optical System with Ballistic Focusing of a Powerful Deuterium Atom Beam Injector for Plasma Heating

Physics of Atomic Nuclei - To heat the plasma in the TCV tokamak (Lausanne, Switzerland), a charge exchange injector of a focused beam of fast deuterium atoms with an energy of 30 keV, a power of 1...     

Multineutron photonuclear reactions on the <Superscript>197</Superscript>Au isotope

An experiment on irradiation of the ¹⁹⁷Au isotope by a beam of bremsstrahlung γ-rays of maximum energy E _γ ^m = 70 MeV has been carried out at the RTM-70 race-track microtron of the INP MSU. Residual activity spectra of the irradiated sample were measured. Multiparticle photonuclear reactions on the ¹⁹⁷Au nucleus are observed. Photonuclear reactions with emission of as many as six neutrons are observed for the first time.     

Observation of nanojet-induced modes with small propagation losses in chains of coupled spherical cavities

Nanojet-induced modes (NIMs) and their attenuation properties are studied in linear chains consisting of tens of touching polystyrene microspheres with sizes in the 2-10 micro m range. To couple light to NIMs we used locally excited sources of light formed by several dye-doped fluorescent microspheres from the same chain of cavities. We directly observed the formation and propagation of NIMs by means of the scattering imaging technique. By measuring attenuation at long distances from the source, we demonstrate propagation losses for NIMs as small as 0.5 dB per sphere.     

Exact boundary controllability in problems of transmission for the system of electromagneto‐elasticity

This paper considers transmission problem for the system of electromagneto‐elasticity having piecewise constant coefficients in a bounded domain. The result on exact boundary controllability is obtained provided the interfaces, where the coefficients have a jump discontinuity, are all star‐shaped with respect to one and the same point and the coefficients satisfy a certain monotonicity conditions. Copyright © 2001 John Wiley & Sons, Ltd.     

Photoproton cross section for 26Mg in the giant dipole resonance region

Using bremsstrahlung from the 35 MeV betatron the ²⁶Mg(γ, xp) reaction cross section has been obtained in the excitation energy region up to 29 MeV. The role of isospin splitting in the formation of a giant dipole resonance is discussed in the case of light nuclei.