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arXiv · 1001.4080

New limit on a varying proton-to-electron mass ratio from high-resolution optical quasar spectra

Adrian L. Malec·Ruth Buning·Michael T. Murphy·Nikola Milutinovic·S. L. Ellison·J. Xavier Prochaska·Lex Kaper·Jason Tumlinson·Robert F. Carswell·Wim Ubachs
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Abstract

Molecular transitions recently discovered at redshift z_abs=2.059 toward the bright background quasar J2123-0050 are analysed to limit cosmological variation in the proton-to-electron mass ratio, mu=m_p/m_e. Observed with the Keck telescope, the optical spectrum has the highest resolving power and largest number (86) of H_2 transitions in such analyses so far. Also, (7) HD transitions are used for the first time to constrain mu-variation. These factors, and an analysis employing the fewest possible free parameters, strongly constrain mu's relative deviation from the current laboratory value: dmu/mu =(+5.6+/-5.5_stat+/-2.7_sys)x10^{-6}. This is the first Keck result to complement recent constraints from three systems at z_abs>2.5 observed with the Very Large Telescope.

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Adrian L. Malec, Ruth Buning, Michael T. Murphy, Nikola Milutinovic, S. L. Ellison, J. Xavier Prochaska, Lex Kaper, Jason Tumlinson, Robert F. Carswell, Wim Ubachs. 2010-01-22. New limit on a varying proton-to-electron mass ratio from high-resolution optical quasar spectra. https://doi.org/10.1017/s1743921310009580

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