A longer exposition at http://www.newenergytimes.com/v2/sr/WL/media-3rd-party/Widom-LarsenChemForumsLetter.shtml Question 3
and in a separate paper (which I hadn't looked at before) : http://arxiv.org/PS_cache/cond-mat/pdf/0509/0509269v1.pdf By Widom and Larsen: Finally, Widom and Larsen propose that heavy SPP patch electrons are uniquely able to immediately convert almost any locally produced or incident gamma radiation directly into infrared heat energy, thus providing a form of built-in gamma shielding for LENR nuclear reactions.