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 00:00:00 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, Vol. 82, Issue 2; Other Information: DOI: 10.1103/PhysRevA.82.022106; (c) 2010 The American Physical Society; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

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