164 citations · 1.1k across the 34 of their papers we have counts for
9 papers · 1 filter
Constraint on a varying proton-to-electron mass ratio from H2 and HD absorption at z = 2.34
M. Daprà, M. van der Laan, M. T. Murphy +1
Molecular hydrogen absorption in the damped Lyman-alpha system at z = 2.34 towards quasar Q1232+082 is analyzed in order to derive a constraint on a possible temporal variation of…
Constraint on a cosmological variation in the proton-to-electron mass ratio from electronic CO absorption
M. Daprà, M. L. Niu, E. J. Salumbides +2
Carbon monoxide (CO) absorption in the sub-damped Lyman- absorber at redshift , toward the background quasar SDSS J123714.60+064759.5 (J1237+0647), was inve…
Constraint on a varying proton-to-electron mass ratio from molecular hydrogen absorption toward quasar SDSS J123714.60+064759.5
M. Daprà, J. Bagdonaite, M. T. Murphy +1
Molecular hydrogen transitions in the sub-damped Lyman alpha absorber at redshift z = 2.69, toward the background quasar SDSS J123714.60+064759.5, were analyzed in order to search…
A constraint on a varying proton--electron mass ratio 1.5 billion years after the Big Bang
J. Bagdonaite, W. Ubachs, M. T. Murphy +1
A molecular hydrogen absorber at a lookback time of 12.4 billion years, corresponding to 10 of the age of the universe today, is analyzed to put a constraint on a varying proto…
Analysis of Molecular Hydrogen Absorption toward QSO B0642-5038 for a Varying Proton-to-Electron Mass Ratio
Julija Bagdonaite, Wim Ubachs, Michael T. Murphy +1
Rovibronic molecular hydrogen (H) transitions at redshift towards the background quasar B06425038 are examined for a possible cosmological variati…
Constraint on a variation of the proton-to-electron mass ratio from H2 absorption towards quasar Q2348-011
Julija Bagdonaite, Michael T. Murphy, Lex Kaper +1
Molecular hydrogen (H2) absorption features observed in the line-of-sight to Q2348-011 at redshift zabs = 2.426 are analysed for the purpose of detecting a possible variation of th…
Cosmological concordance or chemical coincidence? Deuterated molecular hydrogen abundances at high redshift
J. Tumlinson, A. L. Malec, R. F. Carswell +8
We report two detections of deuterated molecular hydrogen (HD) in QSO absorption-line systems at . Toward J2123-0500, we find (HD) for a sub-DLA with me…
New limit on a varying proton-to-electron mass ratio from high-resolution optical quasar spectra
Adrian L. Malec, Ruth Buning, Michael T. Murphy +7
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-elect…
Keck telescope constraint on cosmological variation of the proton-to-electron mass ratio
Adrian L. Malec, Ruth Buning, Michael T. Murphy +7
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-elect…