e/Induced gamma emission: Hafnium controversy

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has gloss	eng: The nuclear isomer 178m2Hf is a particularly attractive candidate for induced gamma emission experiments, because of its high density of stored energy, 2.5 MeV per nucleus, and long 31-year half life for storing that energy. If radiation from some agent could "trigger" a release of that stored energy, the resulting cascade of gamma photons would have the best chance of finding a pair of excited states with the inverted lifetimes needed for stimulated emission. While induced emission adds only power to a radiation field, stimulated emission adds coherence and the possibility to manipulate gamma ray coherence, even to a small degree would be interesting. The lifetime of the Hafnium isomer is long enough for tractable amounts of material to be collected into experimental targets. Such samples would hold no hazards for personnel working with the material; 1 micro-gram of 178m2Hf has an activity of only 40 micro-Curies.
lexicalization	eng: Induced gamma emission: Hafnium controversy
instance of	(noun) a grey tetravalent metallic element that resembles zirconium chemically and is found in zirconium minerals; used in filaments for its ready emission of electrons atomic number 72, hafnium, Hf

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