Enhanced sensitivity to the time variation of the fine-structure constant and m{sub p}/m{sub e} in diatomic molecules: A closer examination of silicon monobromide

Journal Article · Sun Aug 15 04:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.82.022106· OSTI ID:21448433

Beloy, K; Borschevsky, A; Schwerdtfeger, P ^[1]; Flambaum, V V ^[1]

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1. Centre for Theoretical Chemistry and Physics, New Zealand Institute for Advanced Study, Massey University Auckland, Private Bag 102904, 0745 Auckland (New Zealand)

Recently it was pointed out that transition frequencies in certain diatomic molecules have an enhanced sensitivity to variations in the fine-structure constant {alpha} and the proton-to-electron mass ratio m{sub p}/m{sub e} due to a near cancellation between the fine structure and vibrational interval in a ground electronic multiplet [V. V. Flambaum and M. G. Kozlov, Phys. Rev. Lett. 99, 150801 (2007)]. One such molecule possessing this favorable quality is silicon monobromide. Here we take a closer examination of SiBr as a candidate for detecting variations in {alpha} and m{sub p}/m{sub e}. We analyze the rovibronic spectrum by employing the most accurate experimental data available in the literature and perform ab initio calculations to determine the precise dependence of the spectrum on variations in {alpha}. Furthermore, we calculate the natural linewidths of the rovibronic levels, which place a fundamental limit on the accuracy to which variations may be determined.

• OSTI ID: 21448433
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 2 Vol. 82; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
BARYONS
BROMIDES
BROMINE COMPOUNDS
DIMENSIONLESS NUMBERS
ELECTRONS
ELEMENTARY PARTICLES
ENERGY LEVELS
FERMIONS
FINE STRUCTURE
GROUND STATES
HADRONS
HALIDES
HALOGEN COMPOUNDS
LEPTONS
LINE WIDTHS
MASS
MOLECULES
NUCLEONS
PROTONS
REST MASS
SENSITIVITY
SILICON BROMIDES
SILICON COMPOUNDS
SILICON HALIDES
SOMMERFELD CONSTANT
SPECTRA
VARIATIONS