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Nuclear physics

Long live isomer research

Nature Physics volume 1, pages 81–82 (2005)Cite this article

Excited quantum states in nature are normally extremely short-lived, and this certainly applies to most nuclei. But what makes the metastable nuclear states different? And how can we exploit them for useful applications?

An isomer is an excited quantum-mechanical state of a nucleus, in which a combination of nuclear structure effects inhibits its decay and endows the isomeric state with a lifetime that is longer than expected (some examples are shown in Table 1). The strong force that binds a nucleus together and the exchange of the mediators of this force lead to immeasurably short lifetimes of the order of 10−24 s for most nuclear states. But known isomers in nuclei span the entire range of lifetimes from 1015 years for 180mTa (m = metastable) — longer than the accepted age of the universe — to an informal rule of thumb on the lower side of approximately 1 ns. This inhibition to decay leads to the storage of enormous amounts of energy in these states (104 or 105 times more than chemical energy release). The challenge and potential for scientific discovery today lie in the understanding of the formation of nuclear isomers (through a better comprehension of nuclear structure), the ability to excite and de-excite isomers at will for a broad range of applications from isomeric bombs to a clean source of energy, and the exploration of nuclei with isomeric states in nuclear astrophysics to determine how they affect the creation of the elements in the universe, and how they eventually contribute to the makeup of life in our cosmos.

Table 1 Nuclear isomers. Long-lived isomers store enough energy for many different applications. The key is finding out how to release that energy 'on tap'.
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References

  1. Walker, P. M. & Carroll, J. J. Phys. Today 58, 39–44 (2005).

    Article  Google Scholar 

  2. Walker, P. M. & Dracoulis, G. D. Nature 399, 35–40 (1999).

    Article  ADS  Google Scholar 

  3. Sherman, M. S. Science Technol. Rev. 24–25 (July/August 2005).

  4. Cwiok, S., Heenen, P.-H. & Nazarewicz, W. Nature 433, 705–709 (2005).

    Article  ADS  Google Scholar 

  5. Xu, F. R., Zhao, E. G., Wyss, R. & Walker, P. M. Phys. Rev. Lett. 92, 252501 (2004).

    Article  ADS  Google Scholar 

  6. Schwarzschild, B. Phys. Today 57, 21–24 (2004).

    Article  ADS  Google Scholar 

  7. Walker, P. M., Dracoulis, G. D. & Carroll, J. J. Phys. Rev. C 64, 061302 (2001).

    Article  ADS  Google Scholar 

  8. Belic, D. et al. Phys. Rev. C 65, 035801 (2002).

    Article  ADS  Google Scholar 

  9. Runkle, R. C., Champagne, A. E. & Engel, J. Astrophys. J. 556, 970–978 (2001).

    Article  ADS  Google Scholar 

  10. Sun, Y., Wiescher, M., Aprahamian, A. & Fisker, J. Nucl. Phys. A 758, 765–768 (2005).

    Article  ADS  Google Scholar 

Download references

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Authors and Affiliations

  1. Department of Physics and Institute for Structure & Nuclear Astrophysics, University of Notre Dame, Notre Dame, 46556-5670, Indiana, USA

    Ani Aprahamian & Yang Sun

  2. Ani Aprahamian & Yang Sun

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  1. Ani Aprahamian
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  2. Yang Sun
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Aprahamian, A., Sun, Y. Long live isomer research. Nature Phys 1, 81–82 (2005). https://doi.org/10.1038/nphys150

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