Published March 2009 | Version v1
Journal article

Enhanced effect of quark mass variation in 229Th and limits from Oklo data

  • 1. Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5 (Canada)
  • 2. School of Physics, University of New South Wales, Sydney 2052 (Australia)
  • 3. Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

Description

The effects of the variation of the dimensionless strong interaction parameter Xq=mq/ΛQCD (mq is the quark mass, ΛQCD is the QCD scale) are enhanced about 1.5x105 times in the 7.6 eV ''nuclear clock'' transition between the ground and first excited states in the 229Th nucleus and about 1x108 times in the relative shift of the 0.1 eV compound resonance in 150Sm. The best terrestrial limit on the temporal variation of the fundamental constants, |δXq/Xq|<4x10-9 at 1.8 billion years ago (|X·q/Xq|<2.2x10-18y-1), is obtained from the shift of this Sm resonance derived from the Oklo natural nuclear reactor data. The results for 229Th and 150Sm are obtained by extrapolation from light nuclei where the many-body calculations can be performed more accurately. The errors produced by such extrapolation may be smaller than the errors of direct calculations in heavy nuclei. The extrapolation results are compared with the ''direct'' estimates obtained using the Walecka model. A number of numerical relations needed for the calculations of the variation effects in nuclear physics and atomic spectroscopy have been obtained: for the nuclear binding energy δE/E≅-1.45 δmq/mq, for the spin-orbit intervals δEso/Eso≅-0.22 δmq/mq, for the nuclear radius δr/r≅0.3 δmq/mq (in units of ΛQCD); for the shifts of nuclear resonances and weakly bound energy levels δEr≅10 δXq/Xq MeV

Additional details

Publishing Information

Journal Title
Physical Review. C, Nuclear Physics
Journal Volume
79
Journal Issue
3
Journal Page Range
p. 034302-034302.8
ISSN
0556-2813
CODEN
PRVCAN

Optional Information

Notes
(c) 2009 The American Physical Society