The nuclear interaction at Oklo 2 billion years ago
Yasunori Fujii
Nihon Fukushi University, Handa, Aichi, 475-0012 Japan
and
Institute of Cosmic Ray Research (ICRR), University of Tokyo,
Tanashi, Tokyo, 188-8502 Japan
Akira Iwamoto, Tokio Fukahori, Toshihiko Ohnuki, Masayuki Nakagawa
Japan Atomic Energy Research Institute (JAERI)
Tokai-mura, Naka-gun, Ibaraki, 319-1195 Japan
Hiroshi Hidaka
Department of Earth and Planetary Systems Science, Hiroshima University
Higashi-Hiroshima, Hiroshima, 739-8526 Japan
Yasuji Oura
Department of Chemistry, Tokyo Metropolitan University,
Hachioji, Tokyo,
192-0397 Japan
Peter Möller
Theoretical Division, Los Alamos National Laboratory, New Mexico 87545, USA
We re-examine the effort to constrain the time-variability of the coupling
constants of the fundamental interactions by studying the anomalous isotopic
abundance of Sm observed at the remnants of the natural reactors which were in
operation at Oklo about 2 billion years ago, in terms of a possible deviation of
the resonance energy from the value observed today. We rely on new samples that
were carefully collected to minimize natural contamination and also on a careful
temperature estimate of the reactors. We obtain the upper bound
on the fractional rate of change of the
electromagnetic as well as the strong interaction coupling constants. Our
result basically agrees with and even suggests some improvement of the result
due recently to Damour and Dyson. Strictly speaking, however, we find another
range of the resonance energy shift indicating a nonzero time variation of the
constants. We find a rather strong but still tentative indication that this
non-null range can be ruled out by including the Gd data, for which it is
essential to take the effect of contamination into account.
The complete manuscript
is available for download.
This manuscript has been assigned Los Alamos Preprint No LA-UR-98-5377.
Peter Moller
Created 2001, Last modified: Mon July 2 2012