Further evidence for a variable fine-structure constant from Keck/HIRES QSO absorption spectra

  title={Further evidence for a variable fine-structure constant from Keck/HIRES QSO absorption spectra},
  author={Michael T. Murphy and John K Webb and Victor V. Flambaum},
  journal={Monthly Notices of the Royal Astronomical Society},
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 a third Keck/HIRES sample containing 78 absorption systems. We also re-analyse the previous samples, providing a total of 128 absorption systems over the redshift range 0.2 < zabs < 3.7. The results, with raw statistical errors, indicate a small er weighted mean α in the absorption clouds… 

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