The hafnium controversy was a debate over the possibility of 'triggering' rapid energy releases, via gamma ray emission, from a nuclear isomer of hafnium, 178m2Hf. Per event the energy release is 5 orders of magnitude (100,000 times) more energetic than in a typical chemical reaction, but 2 orders of magnitude less than a nuclear fission reaction. In 1998, a group led by Carl Collins of the University of Texas at Dallas reported[1][2] having successfully initiated such a trigger. Signal-to-noise ratios were small in those first experiments, and to date no other group has been able to duplicate these results. Peter Zimmerman (an American nuclear physicist and arms control expert) described claims of weaponization potential as having been based on "very bad science".[3]
^Collins, C.B., Davanloo, F., Iosif, M.; et al. (1999). "Accelerated Emission of Gamma Rays from the 31-yr Isomer of 178Hf Induced by X-Ray Irradiation". Physical Review Letters. 82 (4): 695–698. Bibcode:1999PhRvL..82..695C. doi:10.1103/PhysRevLett.82.695.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^Collins, C.B., Davanloo, F., Rusu, A.C.; et al. (2000). "Gamma emission from the 31-yr isomer of 178Hf induced by x-ray irradiation". Physical Review C. 61 (5): 054305–054305–7. Bibcode:2000PhRvC..61e4305C. doi:10.1103/PhysRevC.61.054305.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^Peter Zimmerman (June 2007). "The Strange Tale of the Hafnium Bomb: A Personal Narrative". American Physical Society. Retrieved 5 March 2016.
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hafniumcontroversy was a debate over the possibility of 'triggering' rapid energy releases, via gamma ray emission, from a nuclear isomer of hafnium...
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