Constraining variations in the fine-structure constant, quark masses and the strong interaction

  title={Constraining variations in the fine-structure constant, quark masses and the strong interaction},
  author={Michael T. Murphy and Victor V. Flambaum and John K Webb and V. V. Dzuba and Jason Xavier Prochaska and Arthur M. Wolfe},
  journal={Lecture Notes in Physics},
We present evidence for variations in the fine-structure constant from Keck/HIRES spectra of 143 quasar absorption systems over the redshift range 0.2 1.8). Our most robust estimate is a weighted mean Δα/α = (-0.57 ′ 0.11) x 10 - 5 . We respond to recent criticisms of the many-multiplet method used to extract these constraints. The most important potential systematic error at low-z is the possibility of very different Mg heavy isotope abundances in the absorption clouds and laboratory: higher… 
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Keck Telescope Constraint on Cosmological Variation of the Proton-to-Electron Mass Ratio
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The results of a search for time variability of the fine structure constant alpha using absorption systems in the spectra of distant quasars find no systematic effects which can explain the results.
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Strong ultraviolet resonance transitions are observed routinely both in the Galactic interstellar medium and in quasar absorption systems. The quality of the astronomical spectroscopic data now
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We present an intermediate-resolution, high signal-to-noise ratio spectrum of the z = 2.7268 galaxy MS 1512-cB58 obtained with the Low Resolution Imaging Spectrograph (LRIS) on the Keck I telescope
Further evidence for a variable fine-structure constant from Keck/HIRES QSO absorption spectra
We have previously presented evidence for a varying fine-str ucture constant, α, in two independent samples of Keck/HIRES QSO absorption spectra. Here we present a detailed manymultiplet analysis of
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Quasar (QSO) absorption spectra provide an extremely useful probe of possible cosmological variation in various physical constants. Comparison of H i 21-cm absorption with corresponding molecular
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Comparison of quasar (QSO) absorption spectra with laboratory spectra allows us to probe possible variations in the fundamental constants over cosmological time-scales. In a companion paper we