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Observations on the long-lived Mossbauer effects of ^93mNb.

ABSTRACT: Several observations of the Nb long-lived Mossbauer phenomena are presented, in consequence of an irradiation increased by an order of magnitude compared with previous work. These are 1) two β decays of ¹⁸²Ta and ^92mNb are enhanced, i.e., ¹⁸²Ta is now 200 times faster than in previous results while ^92mNb is twice as fast as normal; 2) γs emitted from two β decays compete to eject electrons in a winner-takes-all rule, rather than by superposition; 3) abrupt spectral changes reveal three decay phases of ¹⁸²Ta; 4) the biphoton γγ of ^93mNb is released from the sample for the first time; 5) the γγ distribution is narrow, in contrast to the broad γγ spectrum obtained from independent nuclei; 6) Nb K-lines super-radiate along the long sample axis; 7) collective scattering of multipolar MeV γs. The manipulation of nuclear decay speeds demonstrated here highlights a potential application of this work in cleaning up the nuclear wastes.

SUBMITTER: Cheng Y

PROVIDER: S-EPMC5099924 | biostudies-literature |

REPOSITORIES: biostudies-literature

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