Table of contents

At wide angles in a storage ring environment, a substantial part of the energy seen by a hadron calorimeter can be in the form of very low momentum particles such as jet fragments or resonance cascade decay products. Data are presented on the deviations from Gaussian resolution and linear response for such low momentum particles. The differing responses to incident e^-, μ^-, π^+-, K^+-, p and at momenta below 10 GeV/c are also compared.

In addition, we discuss the significance of angle effects for a 4π calorimeter, and the problems of combining data from calorimeters with different physical characteristics. Experimental data are presented on the difference in hadron response between a fine grain ("electromagnetic") lead calorimeter and a coarser ("hadron") iron calorimeter, and on the dependence of the response on the energy sharing between the two calorimeters.

The hadron calorimeter for the UA1 experiment at the CERN SPS proton-antiproton collider consists of a lead-scintillator sandwich plus an iron-scintillator sandwich with wavelength shifter readout. We have tested prototype modules in muon and hadron beams in the momentum range from 0.7 to 90 GeV/c.

For several angles of incidence, we have studied the uniformity of the response to hadrons as a function of position. This has included regions where there is reduced sensitivity due to mechanical constraints and the presence of the wavelength shifter readout. The response, resolution and degree of shower containment were measured as a function of incident momentum.

The level structure of ⁸³Kr up to about 3 MeV has been studied using the ⁸⁰Se(α, nγ) reaction. Spin and parity assignments are based on singles and coincidence γ-ray spectra, on measured angular distributions and on excitation curves. The results are discussed in terms of a particle-rotor model.

A systematic calculation of high-spin potential-energy surfaces in the -γ-plane has been performed within the cranked Nilsson-Strutinsky model. In all, results from 407 even-even nuclei ranging from ⁶⁶₃₄Se to ²¹⁸₈₄Po are available, each at about ten different spin values. In the case of I > 0 the pairing interaction is neglected, while it is accounted for at spin zero. Approximately 4200 different potential-energy surfaces are presented in the compact form of micro-fiche films.

The observed spectrum of ¹⁶⁸Er is analyzed within the general framework applicable to deformed nuclei with rotational spectra. The evidence implies a major anharmonicity in the γ vibrational motion. These results are found to be in rather serious disagreement with a recent interpretation of the spectrum based on the interacting boson model. The general structure of the spectrum implied by this model for deformed nuclei is discussed in an appendix. A postscript discusses a major inconsistency in the energy scale employed in the boson analysis.

Satellite structure of the spectrum resulting from the consideration of configurations mixing was studied. These are the transitions of the type 1s2s²2pⁿ-1s²2pⁿ⁺¹ and 1s2pⁿ-1s²2s²2p^n-3. Transition energies (eV) and probabilities (10¹³ s^-1) were calculated for all possible values of "n". The perturbations theory by 1/Z was used in the calculations. Relativistic effects were taken into account within the frames of the Breit operator. The obtained numerical values of transition probabilities are averaged over J, J' (Tables I-IV) and then over LS, L'S' (Table V). Minimum and maximum energies of transition being studied are given for transition energies (E). Numerical results are presented for Mg, Al, Si ions.

Kinetic energy shifts of the Auger and photoelectrons between free atoms and their solid samples are studied for three series of consecutive elements: Na to Si, Cu to Se and Pd to Ba. The free atom binding and Auger energies are evaluated semiempirically for the elements for which experimental atomic data are not available. The obtained energies are also compared to the corresponding values from other calculation methods. With the aid of calculated atomic Auger energies and measured molecular Auger spectra also the molecular Auger shifts are obtained for several molecules. Experimental values for solid state shifts are obtained either from direct simultaneous vapour-solid measurements or from comparison between calculated or measured atomic energies and separate solid state measurements. The solid state Auger shifts are also calculated by applying the thermochemical model to the Auger process. Good agreement between calculated and experimental shift values are found through the studied series.

The influence of random inhomogeneities in a nonlinear medium on the resonant interaction of a wave beam triplet is considered. It is shown that the presence of a random desynchronism at the "up-conversion" of quasioptical beams leads to a complete compensation of the diffractional incoherence and to the establishment of a spatially inhomogeneous regime of the interaction with the transformation coefficient equal to 50%. A consequence of multiple scattering of interacting beams is the possibility of a complete reproduction of the correlational properties of low-frequency incoherent radiation by a generated high-frequency field.

The contribution to the absorptance of a semi-infinite metal from electron-hole pair excitations, in terms of the inverse dielectric function of the metal, is discussed. A simple approximation is introduced for the full inverse dielectric function, which only depends on the unperturbed ground state electron density. To illustrate some of the basic features involved in the dielectric response of the metal this expression is used in the three-step model of photoemission to account for the experimentally measured photoyield spectrum of aluminum, below the bulk plasmon frequency.