A new constraint on the time dependence of the proton-to-electron mass ratio

Abstract

Abstract. A new limit on the possible cosmological variation of the proton-to-electron mass ratio µ = m p /m e is estimated by measuring wavelengths of H 2 lines of Lyman and Werner bands from two absorption systems at z abs = 2.5947 and 3.0249 in the spectra of quasars Q 0405−443 and Q 0347−383, respectively. Data are of the highest spectral resolution (R = 53 000) and S/N ratio (30÷70) for this kind of study. We search for any correlation between z i , the redshift of observed lines, determined using laboratory wavelengths as references, and K i , the sensitivity coefficient of the lines to a change of µ, that could be interpreted as a variation of µ over the corresponding cosmological time. We use two sets of laboratory wavelengths, the first one, Set (A) (Abgrall et al. 1993, J. Mol. Spec., 157, 512), based on experimental determination of energy levels and the second one, Set (P) (Philip et al. 2004, Can. J. Chem., 82, 713), based on new laboratory measurements of some individual rest-wavelengths. We find ∆µ/µ = (3.05 ± 0.75) × 10 −5 for Set (A), and ∆µ/µ = (1.65 ± 0.74) × 10 −5 for Set (P). The second determination is the most stringent limit on the variation of µ over the last 12 Gyr ever obtained. The correlation found using Set (A) seems to show that some amount of systematic error is hidden in the determination of energy levels of the H 2 molecule.

Time variation of the fine structure constant and of the Higgs vacuum expectation value on cosmological time scales

“…These astronomical observations suggest a possible variation of the fine structure constant and the electron-to-proton mass ratio (Webb et al 1999(Webb et al , 2001Murphy et al 2001aMurphy et al ,b, 2003Ivanchik et al 2005;Reinhold et al 2006;Tzanavaris et al 2007). However, another analysis of similar astronomical data gives null variation of the fine structure constant (Martínez Fiorenzano et al 2003;Quast et al 2004;Bahcall et al 2004;Srianand et al 2004;King et al 2008;Thompson et al 2009;Malec et al 2010).…”

New cosmological constraints on the variation of fundamental constants: the fine structure constant and the Higgs vacuum expectation value

“…The astronomical methods consist on the spectroscopic analysis of high-redshift quasar-absorption systems. Some of these astronomical observations suggest a possible variation of the fine structure constant and of the electron-to-proton mass ratio (Webb et al 1999(Webb et al , 2001Murphy et al 2001aMurphy et al ,b, 2003Ivanchik et al 2003Ivanchik et al , 2005Reinhold et al 2006;Tzanavaris et al 2007;Levshakov et al 2002b;Potekhin et al 1998). However, another analysis of similar astronomical data gives a null variation of the fine structure constant (Martínez Fiorenzano et al 2003;Quast et al 2004;Bahcall et al 2004;Srianand et al 2004;King et al 2008; Thompson et al 2009;Malec et al 2010).…”

The Confrontation Between General Relativity and Experiment

“…2.6 -3.0 Spectra in distant quasars [199] In a similar manner, recent reanalyses of decay rates of 187 Re in ancient meteorites (4.5 billion years old) gave the bound˙E M / EM < 3.4 × 10 −16 yr −1 [312].…”