This report follows the radiochemical study of fission and spallation products produced by bombardment of U-235 with 18- to 16-Mev helium ions and of the spallation products produced by 8- to 23-Mev deuteron bombardments of Np-237.

At high excitation energies, competition of proton and c-particle emission with neutron emission becomes important. For low excitation, the competition between Y-emission, neutron emission, and fission should be taken into account. To aid in the evaluation of this competition an experiment has been performed to measure the number and energy spectrum of the protons and c-particles emitted in the high energy bombardment of uranium with protons, deuterons, and c-particles.

From introduction: "This report is an attempt to examine, semiquantitavely, the way the competition between neutron emission and fission varies for heavy nuclei as a function of nuclear type and excitation energy. Many of the ideas herein are the results of discussions with R. H. Goeckermann and W. Heckrotte of the University of California Radiation Laboratory."

Progress report on programs in target research and in accelerator research.

Certain aspects of mating behavior in two different types of Drosophila melanogaster females (Basc and Bv) and wildtype males (Samarkand) have been investigated and compared.

Progress report on biological studies of radiation effects, metabolic properties of various materials, health chemistry, health physics.

The pion-pion interaction is of great theoretical importance and must be understood before the other and more familiar interactions can be systematically analyzed. Therefore, various experiments to verify the existence of a P resonance in the w w system are proposed.

"This report presents some of the theory of operation of the Mirror Machine, and summarizes the experimental work which has been carried out...The modus operandi of the Mirror Machine is to create, heat and control a high temperature plasma by means of externally generating magnetic fields."

The following report is a general monthly progress report conducted by the radiation laboratory of the University of California discussing experimental physics, theoretical physics, the MTA target physics program, accelerator construction and operation, biology and medicine, and a plant and equipment report. The period being covered is January 15, 1954 to February 15, 1954.

The thermal decomposition of the higher oxides of praseodymium and americium have been investigated.

Report of progress on the metabolic properties of various materials, biological studies of radiation effects, health chemistry and physics.

Quarterly progress report for the Chemistry Division of the University of California Radiation Laboratory: nuclear chemistry, bio-organic chemistry, metals and high temperature thermodynamics, basic chemistry, and chemical engineering.

Quarterly report on projects - special M.T.A. distribution

This revised version contains material published in the two years since the original report was issued in January 1960. The report covers the history of the discovery of fission, fission theory, and the probability of fission. It discusses the distribution of mass in fission, the distribution of nuclear charge in fission, kinetic energy of fission fragments, and the role of neutrons and gamma rays in fission.

Certain isotopes in the region of the heaviest elements have been produced by cyclotron and pile bombardment techniques, and their nuclear decay properties have been investigated. The orbital electron capture decay of At210, At211, Np234, Np235, Pu234, Pu237, and Am242m has been studied and decay schemes have been proposed. In addition, the alpha spectra of Po211, At210, and At211 have been observed.

Quarterly report of the Chemistry Division at the University of California Radiation Laboratory providing updates for each department about current findings and ongoing research.

Figures 1 and 2 summarize total decay energies for the four radioactive series. The alpha-decay energy obtained by measuring the energy of the alpha particle leading to the ground state includes the energy of the recoil nucleus. The curve shown in figure 3 defines in broad outline the conditions and regions of alpha instability. A great deal more is to be learned from a more detailed examination of the region where alpha radioactivity is prominent. Of great value to the experimentalist is that he is able to predict alpha energies, and the agreement between predicted and measured values often serves as a criterion for isotopic assignment. A number of systems for correlating alpha decay energies have been employed, and that perhaps most widely used is illustrated in figure 4. Here the isotopes of each element on a mass number vs. energy plot are joined, resulting in a family of curves which over a wide region comprise a series of nearly parallel lines.

Abstract: "With magnetic alpha-particle and electron high-resolution spectrographs and scintillation gamma-ray spectrometers, a study was made of the nuclear decay of a number of members of the actinium family - U-235, Th-227, Ra-223, Em-219, Po-215, and Bi-211. Decay schemes are presented for each of these nuclides, together with such correlations as are possible with present theoretical nuclear models. The decay scheme of U-235 and a portion of that of Th-227 are interpretable in terms of the collective model and a spherical shell-model characteristics; however, the intermediate nuclides present complexities not well understood."

Summary: The activity coefficient of Pu(Cl04)4 was measured in perchloric acid solutions. The procedure used was to measure the extraction of the neutral plutonium(IV)-TTA chelate into benzene-TTA solutions at different perchloric acid concentrations. Equations are presented which show the relation of the extraction coefficients, obtained in the above manner, to the activity coefficient of plutonium(IV) per-chlorate. The activity coefficient of Pu(Cl0~)4 is similar to that of a strong acid, e.g., perchloric acid, in that its value increases rapidly when the perchloric acid concentration becomes greater than 2M. The distribution coefficient of TTA between benzene and aqueous perchloric acid solutions was found first to decrease slightly and then to increase two fold as the perchloric acid was varied from 0.01 to 6M. The activity coefficient of the uranous-TTA chelate in benzene was calculated from the results of solubility measurements. The values of the activity coefficient of UK4 are,within experimental error, identical with the values of the activity coefficient of TTA itself.