[en] Studies of close binary stars are being persued more vigorously than ever, with about 3000 research papers and notes pertaining to the field being published during the triennium 1976-1978. Many major advances and spectacular discoveries were made, mostly due to increased observational efficiency and precision, especially in the X-ray, radio, and ultraviolet domains. Progress reports are presented in the following areas: observational techniques, methods of analyzing light curves, observational data, physical data, structure and models of close binaries, statistical investigations, and origin and evolution of close binaries. Reports from the Coordinates Programs Committee, the Committee for Extra-Terrestrial Observations and the Working Group on RS CVn binaries are included. (Auth./C.F.)

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[en] A review is made of some recent developments in the application of the Bohr Hamiltonian to transitional nulcei. The primary concern is to understand the advantages and limitations inherent to the basic model and its many variants. (author)

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[en] An RPA formalism is developed to investigate the existence and properties of slow collective rotation around a non-symmetry axis, when there already exists a large angular momentum K along the symmetry axis built up by aligned single-particle spins. It is found necessary to distinguish between the collectivity and the repeatability of the rotational excitations. First the formalism is applied to bands on hihg-K isomers in the well-deformed nucleus ¹⁷⁶Hf, where the rotational-model picture is reproduced for intermediate K-values in agreement with experiment. At high K there is a suppression of the collectivity corresponding to the diminishing vector-coupling coefficient of the rotational model, but the repeatability actually improves. The moment of inertia is predicted to remain substantially smaller than the rigid-body value so the bands slope up steeply from the yrast line at spins where pairing effects are gone. A second application is to the initially spherical nucleus ²¹²Rn, which is believed to acquire an oblate deformation that increases steadily with K due to the oblate shape of the aligned orbitals. In this case the repeatable excitations come higher above the yrast line than in ¹⁷⁶Hf, even at comparable deformations. Some collective states may occur very close to yrast, but these are more like dressed singleparticle excitations. The main differences between the two nuclei studied is interpreted as a general consequence of their different shell structure. (author)

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[en] In a brief introduction the main aspects of neutron stars and black holes, and their place in the history of astronomy are presented. Stellar evolution is then discussed, energy production through thermonuclear reactions, nucleosynthesis, and stellar structure. The laws for hot gases are also discussed, and applied to main series stars. Pauli's exclusion princip and the degeneration of an electron gas are also treated. The laws for a cold materi are then discussed, leading to release of neutrons at the NDP. Considerations of hydrostatic balance and stability are presented for spherical stars, and finally the development towards the end phase, collapse, leading to white dwarfs, neutron stars and black holes is treated. (JIW)

[en] A numerically feasible method, based on the use of deformed phonons, is developed for the diagonalization of the collective quadrupole Hamiltonian for a system with an odd particle coupled to an anharmonic even core. Examples: the transition from prolate to oblate via γ-unstable shapes and furthermore the hsub(9/2) spectra of the nuclei ¹⁸⁷Ir and ¹⁹⁷Tl. (Auth.)

[en] The second part of the article is almost wholly concerned with the evolution and properties of white dwarf stars. (JIW)