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Several magnetic bubble material samples were exposed to fission neutrons and Co-60 gamma rays in order to assess their radiation sensitivity. Magnetic property measurements were made before and after irradiation. No changes in magnetic properties were observed in any sample up to 4 x to the 14th power n/sq cm and 10 to the 8th power to 10 to the 9th power Rad(Si) Co-60. Table 1 summarizes the results and also gives other results on other samples which were irradiated at AFCRL and evaluated elsewhere. The in-house measurements consisted of coercivity, magnetization, wall energy, and characteristic length. Appendix A gives a detailed data analysis of the inhouse experimental results on three samples. The remainder of this report consists of a brief summary of the experimental measurements made at AFCRL and also the details of the radiation exposures.

The experimental techniques for low temperature electron irradiation of metals are discussed in detail. Problems discussed include those of dosimetry, temperature measurement, sample preparation and data analysis. (Author).

Polycrystalline platinum and palladium were bombarded with monoenergetic electrons at temperatures below 9K. Changes in electrical resistivity R(E) = delta rho/electron-sq cm were measured in the energy range 1.1 to 3.0 MeV. The experimental values found in this interval are consistent with displacement threshold energies of 37 eV for Pt and 34 eV for Pd. The resistivities per unit defect concentration were found to be 0.00075 and 0.0009 ohm-cm for Pt and Pd respectively. The threshold energies found here, together with values reported for other face centered cubic elements, are shown to be directly proportional to atomic number and inversely proportional to the lattice parameter. It is also shown that the resistivities per unit defect concentration can be correlated with the resistivity at 0C. Analysis of the energy dependence of the damage production indicates atomic displacement cascades are markedly inhibited, which is consistent with deuteron damage studies. Alternative multiple displacement models and possible mechanisms are discussed. (Author).

The effect of Co-60 gamma ray incidence angle on dose enhancement at interfaces of dissimilar materials has been measured. Materials studied were gold, aluminum, and beryllium. Maximum enhancement was found at normal incidence with the low atomic numbered material facing the radiation source and the minimum at 180 degrees. The experimental results were compared to Monte Carlo calculations at lower energies.

Exact relativistic calculations of the cross section for atomic displacement in platinum were compared with recent electron-irradiation data in an attempt to determine whether such data can reveal detailed features of the probability-of-displacement function.

Report into the Loss of the SS Titanic is a complete re-evaluation of the loss of Titanic based on evidence that has come to light since the discovery of the wreck in 1985. This collective undertaking is compiled by eleven of the world's foremost Titanic researchers – experts who have spent many years examining the wealth of information that has arisen since 1912. Following the basic layout of the 1912 Wreck Commission Report, this modern report provides fascinating insights into the ship itself, the American and British inquiries, the passengers and crew, the fateful journey and ice warnings received, the damage and sinking, rescue of survivors, the circumstances in connection with the SS Californian and SS Mount Temple, and the aftermath and ramifications that followed the disaster. The book seeks to answer controversial questions, such as whether steerage passengers were detained behind gates, and also reveals the names and aliases of all passengers and crew who sailed on Titanic's maiden voyage. Containing the most extensively referenced chronology of the voyage ever assembled and featuring a wealth of explanatory charts and diagrams, as well as archive photographs, this comprehensive volume is the definitive 'go-to' reference book for this ill-fated ship.

Essays on the relationship between perceptual experience and scientific thought—an introduction to the phenomenology of science.