A helium-mercury direct nuclear pumped laser

Abstract
A 6150‐Å He‐Hg laser, pumped solely by the 1n (10B,α) 7Li nuclear reaction, has been achieved using the Sandia SPRII reactor. The optimum conditions for lasing were 600 Torr total pressure with 2.5 mTorr Hg partial pressure, with a threshold for lasing of ∼1016 n/cm2 sec. This is the first visible‐wavelength laser having nuclear energy as its only source of excitation.