Salumbides EJ, Bailly D, Khramov A, Wolf AL, Eikema KSE, Vervloet M, Ubachs W. Improved laboratory values of the H2 Lyman and Werner lines for constraining time variation of the proton-to-electron mass ratio.
PHYSICAL REVIEW LETTERS 2008;
101:223001. [PMID:
19113480 DOI:
10.1103/physrevlett.101.223001]
[Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Indexed: 05/27/2023]
Abstract
Two distinct high-accuracy laboratory spectroscopic investigations of the H2 molecule are reported. Anchor lines in the EF1Sigmag+-X1Sigmag+ system are calibrated by two-photon deep-UV Doppler-free spectroscopy, while independent Fourier-transform spectroscopic measurements are performed that yield accurate spacings in the B1Sigmau+-EF1Sigmag+ and I1Pig-C1Piu systems. From combination differences accurate transition wavelengths for the B-X Lyman and the C-X Werner lines can be determined with accuracies better than approximately 5 x 10(-9), representing a major improvement over existing values. This metrology provides a practically exact database to extract a possible variation of the proton-to-electron mass ratio based on H2 lines in high-redshift objects. Moreover, it forms a rationale for equipping a future class of telescopes, carrying 30-40 m dishes, with novel spectrometers of higher resolving powers.
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