Observation of the (3)He(n, tp) Reaction by Detection of Far-Ultraviolet Radiation.
We have detected Lyman alpha radiation, 121.6 nm light produced from the n = 2 to n = 1 transition in atomic hydrogen, as a product of the (3)He(n, tp) nuclear reaction occurring in a cell of (3)He gas. The predominant source of this radiation appears to be decay of the 2p state of tritium produced by charge transfer and excitation collisions with the background (3)He gas. Under the experimental conditions reported here we find yields of tens of Lyman alpha photons for every neutron reaction. These results suggest a method of cold neutron detection that is complementary to existing technologies that use proportional counters. In particular, this approach may provide single neutron sensitivity with wide dynamic range capability, and a class of neutron detectors that are compact and operate at relatively low voltages.
Ionizing Radiation Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8461.
Alan K
AK
Thompson
Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742.
Michael A
MA
Coplan
Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742.
John W
JW
Cooper
Institute for Physical Science and Technology, University of Maryland, College Park, MD 20740.
Patrick P
PP
Hughes
Electron and Optical Physics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8411.
Robert E
RE
Vest
Electron and Optical Physics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8410.
Charles
C
Clark
3He; Lyman alpha radiation; neutron detection; thermal neutron detection