The Nucleus

A nuclear radiation effects conference was held in Toronto during the week of 17 June 1963 in conjunction with the Summer General Meeting of the IEEE. Altogether, there were ten half-day sessions at which a total of forty papers were presented treating the effects of reactor, weapon, and space radiatio~ environments on a variety of electronic materials, piece parts and circuits. In this issue we are presenting a number of papers which were given at the conference. Unfortunately some authors of the conference papers had prior commitments for pub1ication and so their papers could not be included. The issue is devided into three sections. The first consists of two invited papers which are tutorial. These provide an excellent summary of the state of the art in many aspects of "permanent" damage and transient-radiation effects. The following two sections contain contributed papers which have been divided into two categories determined by the time history of the radiation source. Experiments performed with so~rces whose radiation rate is more or less constant in time are treated first. This section includes papers concerned wIth space radiation, transit radiation, and steady state sources used for permanent damage studies. The second category, or third section, includes papers on phenomena which are observed when pulsed sources such as flash x-ray machines, 1inacs and pulsed reactors are used. As a final word on organization, we should 1ike to emphasize that "permanent" damage may result from pulsed as well as from steady state radiation. Hence, one who is only interested in "permanent" radiation effects may still find valuable information in all three sections.