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arXiv 0807.4943nucl-thhep-phphysics.atom-ph
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229 Th中夸克质量变化的增强效应和Oklo数据的极限

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

V. V. Flambaum, R. B. Wiringa

摘要:

研究了无量纲强相互作用参数Xq=mq/Lambda{QCD}的变化对量子力学的影响(mq是夸克质量,在229 Th核的基态和第一激发态之间的7.6 eV“核钟”跃迁中,150 Sm中0.1eV复合共振的相对位移增加了8倍。|delta(Xq)/Xq| 1998年10月29日,2008年10月29日,2008年10月29日,2008年10月29日,|d(Xq/Xq)/dt| < 2.2 × 10 ~(**)-18 y ~(**)-1)。~(229)Th和~(150)Sm的计算结果是由轻核外推得到的,这样可以更精确地进行多体计算。这种外推法产生的误差可能小于重核直接计算的误差。外推的结果进行了比较,使用Walecka模型获得的“直接”估计。得到了计算核物理和原子光谱中变分效应所需的一些数值关系式:对核结合能δ(E)/E ~ -1.45 δ(mq)/mq,对自旋轨道间距δ(Eso)/Eso ~ -0.22 δ(mq)/mq,对核半径δ(r)/r ~ 0.3 δ(mq)/mq(单位为λ {QCD});用于核共振和弱束缚能级的位移δ(Er)~ 10 δ(Xq)/Xq MeV。

英文摘要:

The effects of the variation of the dimensionless strong interaction parameter Xq=mq/Lambda{QCD} (mq is the quark mass, Lambda{QCD} is the QCD scale) are enhanced about 1.5 x 10**5 times in the 7.6 eV "nuclear clock" transition between the ground and first excited states in the 229Th nucleus and about 1 x 10**8 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, |delta(Xq)/Xq| < 4 x 10**-9 at 1.8 billion years ago (|d(Xq/Xq)/dt| < 2.2 x 10**-18 y**-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 delta(E)/E ~ -1.45 delta(mq)/mq, for the spin-orbit intervals delta(Eso)/Eso ~ -0.22 delta(mq)/mq, for the nuclear radius delta(r)/r ~ 0.3 delta(mq)/mq (in units of Lambda{QCD}); for the shifts of nuclear resonances and weakly bound energy levels delta(Er) ~ 10 delta(Xq)/Xq MeV.

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