Editor's Summary
28 July 2005
Earthly powers
The KamLAND experiment located in the Kamioka mine one kilometre beneath the Japanese Alps was primarily designed to detect antineutrinos produced by nuclear reactors. But radioactive elements in the Earth also release antineutrinos — known as geoneutrinos — and KamLAND should be sensitive enough to detect these too. And detect them it has. About 20 antineutrinos with characteristics typical of the products of uranium-238 and thorium-232 decay have so far been recorded. This opens up an exciting new era for geophysicists. Using geoneutrinos it should be possible to build up a three-dimensional image of the Earth's interior, and to establish how much geothermal heat is released by radioactive decay. On the cover, the half-globe to the left gives the neutrino rate at KamLAND from different locations on and beneath the Earth's surface.
News and Views: Earth sciences: Ghosts from within
The first detection of geoneutrinos from beneath our feet is a landmark result. It will allow better estimation of the abundances and distributions of radioactive elements in the Earth, and of the Earth's overall heat budget.
William F. McDonough
doi: 10.1038/436467a
Article: Experimental investigation of geologically produced antineutrinos with KamLAND
T. Araki, S. Enomoto, K. Furuno, Y. Gando, K. Ichimura, H. Ikeda, K. Inoue, Y. Kishimoto, M. Koga, Y. Koseki, T. Maeda, T. Mitsui, M. Motoki, K. Nakajima, H. Ogawa, M. Ogawa, K. Owada, J.-S. Ricol, I. Shimizu, J. Shirai, F. Suekane, A. Suzuki, K. Tada, S. Takeuchi, K. Tamae, Y. Tsuda, H. Watanabe, J. Busenitz, T. Classen, Z. Djurcic, G. Keefer, D. Leonard, A. Piepke, E. Yakushev, B. E. Berger, Y. D. Chan, M. P. Decowski, D. A. Dwyer, S. J. Freedman, B. K. Fujikawa, J. Goldman, F. Gray, K. M. Heeger, L. Hsu, K. T. Lesko, K.-B. Luk, H. Murayama, T. O'Donnell, A. W. P. Poon, H. M. Steiner, L. A. Winslow, C. Mauger, R. D. McKeown, P. Vogel, C. E. Lane, T. Miletic, G. Guillian, J. G. Learned, J. Maricic, S. Matsuno, S. Pakvasa, G. A. Horton-Smith, S. Dazeley, S. Hatakeyama, A. Rojas, R. Svoboda, B. D. Dieterle, J. Detwiler, G. Gratta, K. Ishii, N. Tolich, Y. Uchida, M. Batygov, W. Bugg, Y. Efremenko, Y. Kamyshkov, A. Kozlov, Y. Nakamura, H. J. Karwowski, D. M. Markoff, K. Nakamura, R. M. Rohm, W. Tornow, R. Wendell, M.-J. Chen, Y.-F. Wang and F. Piquemal
doi: 10.1038/nature03980