Effect of α variation on the vibrational spectrum of Sr_ {2}

Physical Review A (Impact Factor: 2.81). 12/2011; 84(6). DOI: 10.1103/PhysRevA.84.062114
Source: arXiv


We consider the effect of α variation on the vibrational spectrum of Sr2 in the context of a planned experiment to test the stability of μ≡me/mp using optically trapped Sr2 molecules [ Zelevinsky et al. Phys. Rev. Lett. 100 043201 (2008); Kotochigova et al. Phys. Rev. A 79 012504 (2009)]. We find the prospective experiment to be 3 to 4 times less sensitive to fractional variation in α as it is to fractional variation in μ. Depending on the precision ultimately achieved by the experiment, this result may give justification for the neglect of α variation or, alternatively, may call for its explicit consideration in the interpretation of experimental results.

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