For pioneering nuclear structure studies with radioactive ion beams, development of innovative software for gamma ray spectroscopy, and significant contributions to gamma ray tracking detectors.
For far-reaching accomplishments on national security issues relating to nuclear weapons proliferation, security of nuclear materials, and counterterrorism.
For original studies of the genetic effects of radiation in mammals. A world authority on mammalian mutagenesis, he and co-workers provided the experimental basis for estimating the genetic hazards of radiation to man and for the corresponding recommendations of national and international standards bodies