A tale of openness and secrecy: The Philadelphia Story
A now little-known manuscript prepared by nine young physicists as a statement about the futility of scientific secrecy quickly became a test of the limits of free discourse in the nuclear age.
A State of Rumor: Low Knowledge, Nuclear Fear, and the Scientist as Security Risk
In January 1954, Alan T. Waterman, director of the National Science Foundation (NSF), invited Charles B. Hunt, executive director of the American Geological Institute, to serve as a consultant to the NSF’s earth sciences program. Hunt declined, partly because of constraints on his time, but also because he had grown impatient with the regimen of loyalty and security checks required for such positions. “In recent years,” he informed Waterman, “I have become increasingly fed up with the fact that the government seems to be incapable of determining the dependability of a citizen without insulting him. And, I have become increasingly fed up with the fact that the iron curtain of secrecy has been lowered around many scientific activities that are not related to national security. Such an environment simply is distasteful to me, and so much so that I want no more of it.” 1  Such frustrations among scientists were far from unusual in the late 1940s and early 1950s, as loyalty and security tests, once nonexistent, became commonplace in American scientifi c life. Depending on their political proclivities, most scientists viewed such tests as either a patriotic duty, a necessary
Optical emission spectroscopy of self-sustained magnetron sputtering
Abstract The results of plasma investigation during very high power magnetron sputtering processes are presented. Magnetron sputtering during both standard and self-sustained modes was investigated. Owing to very effective target cooling and appropriate magnetic field distribution, the high target power density could be reached (up to ∼1000 W/cm 2 , ∼1.5 A/cm 2 ). A copper target 50 mm in diameter and 7 mm in thickness was used during the experiments. Two modes of magnetron sputtering, i.e. standard and self-sustained, were investigated. Optical emission spectra were measured. The emission intensity of the Cu species as a function of target power density during both magnetron sputtering modes was observed. The spectra were observed in the 200–800 nm wavelength range. When target current rose, the emission intensity of copper ion lines increased and neutrals ones decreased.