Table of contents

This paper derives the equations of motion of two rotating bodies moving in the weak and quasi-static gravitational field of the bodies up to terms of the order (ν, c)². The analysis is used to obtain the equations of motion of: (a) rotating bodies which remain spherically symmetric, (b) rotating fluid bodies which become spheroidal in form. In case (a) the equations of motion of one body depend directly on the rotation of the second body but not on its own rotation. In case (b) the equations of motion of the one body contain terms due to its own rotation which are dependent on its density distribution.

A magnetic spectrograph has been constructed for the measurement of the angular distribution of charged particles emitted in the deuteron bombardment of nuclei. The spectrograph utilizes the focusing properties of an axially symmetrical field and is capable of focusing protons and α-particles of 3 to 18 MeV and deuterons of 1½ to 9 MeV on a 12 in. long photographic plate, with an energy resolution of 0.25%. The instrument has been used in conjunction with the Liverpool 37in. cyclotron for measurements over an angular range of 5° to 60° at a bombarding energy of 9 MeV. Due to the energy spread of the deuteron beam and the effect of target thickness the total experimental resolution was 0.5 to 0.6%.

Angular distributions have been measured of some of the proton, deuteron and α-particle groups emitted from targets of beryllium, carbon, nitrogen and oxygen when bombarded by 9 MeV deuterons. The proton angular distributions have been compared with those calculated from the stripping theories enabling assignments of spins and parities to be made to levels of the residual nuclei. Calculations have also been made of the relative capture probabilities and reduced widths and in the cases of carbon and nitrogen it was possible to express them in absolute units.

The activities produced in the bombardment of aluminium with protons in the energy range 200-980 MeV have been studied. The ratio of the cross section for the production of ¹¹C from polythene to that for both ¹⁸F and ²⁴Na from aluminium are given in this energy range while cross section ratios of ²⁷Mg, ¹³N and ¹¹C from aluminium are given at an energy of 980 MeV.

The method of atoms in molecules is modified in such a way as to overcome difficulties encountered in previous calculations. The modified theory is applied to two calculations on the ground state of the hydrogen molecule. The more accurate of the two modified calculations leads to an energy curve accurate to within 0.05 electron volt in the range 1 to 4 atomic units of the nuclear separation.

In part I, the divergence which arises when long range inter-atomic forces are represented by power series expansions in the reciprocal of the nuclear separation is shown to be a fundamental property of such series and is not due to the use of an expansion of the perturbing potential in regions of space where it is not valid. It is shown that the series representation is a very convenient one despite its divergence.

In part II, the usual second order perturbation treatment is extended to include higher orders leading to the presence of odd powers in the series and the convergence of the perturbation series is discussed quantitatively. Results are given for H₂⁺ and H₂. Finally the limitations of the series representation are briefly considered.

The probability of auto-detachment from H^-(2s2p)³P is calculated using both a time-dependent perturbation and a time-independent variational method. The values obtained are in essential agreement and are of the order 4 × 10¹² sec^-1, about 100 times smaller than for the similar neutral case of auto-ionization of He(2s2p)³P.