scholarly journals On a possible variation of the proton-to-electron mass ratio: H2 spectra in the line of sight of high-redshift quasars and in the laboratory

2007 ◽  
Vol 241 (2) ◽  
pp. 155-179 ◽  
Author(s):  
W. Ubachs ◽  
R. Buning ◽  
K.S.E. Eikema ◽  
E. Reinhold
Keyword(s):  
High Redshift ◽  
Line Of Sight ◽  
Electron Mass ◽  
Mass Ratio

scholarly journals H2/HD molecular data for analysis of quasar spectra in search of varying constants

2019 ◽  
Vol 622 ◽  
pp. A127 ◽  
Author(s):  
W. Ubachs ◽  
E. J. Salumbides ◽  
M. T. Murphy ◽  
H. Abgrall ◽  
E. Roueff
Keyword(s):  
Vacuum Ultraviolet ◽  
High Redshift ◽  
Sensitivity Coefficient ◽  
Molecular Data ◽  
Oscillator Strengths ◽  
Absorption Lines ◽  
Electron Mass ◽  
Mass Ratio ◽  
Quasar Spectra ◽  
Varying Constants

Context. Absorption lines of H2 and HD molecules observed at high redshift in the line of sight towards quasars are a test ground to search for variation of the proton-to-electron mass ratio μ. For this purpose, results from astronomical observations are compared with a compilation of molecular data of the highest accuracy, obtained in laboratory studies as well as in first-principles calculations. Aims. A comprehensive line list is compiled for H2 and HD absorption lines in the Lyman (B1Σu+ − X1Σg+) and Werner (C1Πu − X1Σg+) band systems up to the Lyman cutoff at 912 Å. Molecular parameters listed for each line i are the transition wavelength λi, the line oscillator strength fi, the radiative damping parameter of the excited state Γi, and the sensitivity coefficient Ki for a variation of the proton-to-electron mass ratio. Methods. The transition wavelengths λi for the H2 and HD molecules are determined by a variety of advanced high-precision spectroscopic experiments involving narrowband vacuum ultraviolet lasers, Fourier-transform spectrometers, and synchrotron radiation sources. Results for the line oscillator strengths fi, damping parameters Γi, and sensitivity coefficients Ki are obtained in theoretical quantum chemical calculations. Results. A new list of molecular data is compiled for future analyses of cold clouds of hydrogen absorbers, specifically for studies of μ-variation from quasar data. The list is applied in a refit of quasar absorption spectra of B0642–5038 and J1237+0647 yielding constraints on a variation of the proton-to-electron mass ratio Δμ/μ consistent with previous analyses.

scholarly journals New Limit on Space-Time Variations in the Proton-to-Electron Mass Ratio from Analysis of Quasar J110325-264515 Spectra

Symmetry ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 344
Author(s):  
T. D. Le
Keyword(s):  
Fine Structure ◽  
Structure Constant ◽  
Space Time ◽  
Fine Structure Constant ◽  
Electron Mass ◽  
Mass Ratio ◽  
Quasar Spectra ◽  
Time Variations ◽  
Using Data ◽  
The Universe

Astrophysical tests of current values for dimensionless constants known on Earth, such as the fine-structure constant, α , and proton-to-electron mass ratio, μ = m p / m e , are communicated using data from high-resolution quasar spectra in different regions or epochs of the universe. The symmetry wavelengths of [Fe II] lines from redshifted quasar spectra of J110325-264515 and their corresponding values in the laboratory were combined to find a new limit on space-time variations in the proton-to-electron mass ratio, ∆ μ / μ = ( 0.096 ± 0.182 ) × 10 − 7 . The results show how the indicated astrophysical observations can further improve the accuracy and space-time variations of physics constants.

scholarly journals Accurate prediction of H3O+and D3O+sensitivity coefficients to probe a variable proton-to-electron mass ratio

2015 ◽  
Vol 454 (3) ◽  
pp. 2292-2298 ◽  
Author(s):  
A. Owens ◽  
S. N. Yurchenko ◽  
O. L. Polyansky ◽  
R. I. Ovsyannikov ◽  
W. Thiel ◽  
...  
Keyword(s):  
Accurate Prediction ◽  
Electron Mass ◽  
Mass Ratio ◽  
Sensitivity Coefficients

scholarly journals The Uehling correction to the energy levels in a pionic atom

2006 ◽  
Vol 84 (2) ◽  
pp. 107-113 ◽  
Author(s):  
S G Karshenboim ◽  
E Yu. Korzinin ◽  
V G Ivanov
Keyword(s):  
Free Electron ◽  
Vacuum Polarization ◽  
Energy Levels ◽  
Analytic Form ◽  
Electron Mass ◽  
Mass Ratio ◽  
Pionic Atom ◽  
Closed Analytic Form

We consider a correction to energy levels in a pionic atom induced by the Uehling potential, i.e., by a free electron vacuum-polarization loop. The calculation is performed for circular states (l = n–1). The result is obtained in a closed analytic form as a function of Zα and the pion-to-electron mass ratio. Certain asymptotics of the result are also presented.PACS Nos.: 12.20.Ds, 36.10.Gv

scholarly journals Fundamental physics and the fine-structure constant

2017 ◽  
Vol 5 (2) ◽  
pp. 46 ◽  
Author(s):  
Michael Sherbon
Keyword(s):  
Fine Structure ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Electron Mass ◽  
Fundamental Constants ◽  
Mass Ratio ◽  
Fundamental Physics ◽  
Weak Force ◽  
Strong Force ◽  
Symmetry Principles

From the exponential function of Euler’s equation to the geometry of a fundamental form, a calculation of the fine-structure constant and its relationship to the proton-electron mass ratio is given. Equations are found for the fundamental constants of the four forces of nature: electromagnetism, the weak force, the strong force and the force of gravitation. Symmetry principles are then associated with traditional physical measures.

scholarly journals First Constraint on Cosmological Variation of the Proton-to-Electron Mass Ratio from Two Independent Telescopes

2011 ◽  
Vol 106 (18) ◽  
Author(s):  
F. van Weerdenburg ◽  
M. T. Murphy ◽  
A. L. Malec ◽  
L. Kaper ◽  
W. Ubachs
Keyword(s):  
Electron Mass ◽  
Mass Ratio

scholarly journals New constraint on cosmological variation of the proton-to-electron mass ratio from Q0528−250

2011 ◽  
Vol 417 (4) ◽  
pp. 3010-3024 ◽  
Author(s):  
Julian A. King ◽  
Michael T. Murphy ◽  
Wim Ubachs ◽  
John K. Webb
Keyword(s):  
Electron Mass ◽  
Mass Ratio

scholarly journals Effects of Positron Density and Temperature on Large Amplitude Ion-acoustic Waves in an Electron - Positron - Ion Plasma

1997 ◽  
Vol 50 (2) ◽  
pp. 309 ◽  
Author(s):  
Y. N. Nejoh
Keyword(s):  
Acoustic Waves ◽  
Large Amplitude ◽  
Density Ratio ◽  
Present Theory ◽  
Electron Mass ◽  
Mass Ratio ◽  
Ion Acoustic Waves ◽  
Ion Plasma ◽  
Electron Positron ◽  
Ion Acoustic

The nonlinear wave structures of large amplitude ion-acoustic waves are studied in a plasma with positrons. We have presented the region of existence of the ion-acoustic waves by analysing the structure of the pseudopotential. The region of existence sensitively depends on the positron to electron density ratio, the ion to electron mass ratio and the positron to electron temperature ratio. It is shown that the maximum Mach number increases as the positron temperature increases and the region of existence of the ion-acoustic waves spreads as the positron temperature increases. The present theory is applicable to analyse large amplitude ion-acoustic waves associated with positrons which may occur in space plasmas.

scholarly journals Robust Constraint on a Drifting Proton-to-Electron Mass Ratio atz=0.89from Methanol Observation at Three Radio Telescopes

2013 ◽  
Vol 111 (23) ◽  
Author(s):  
J. Bagdonaite ◽  
M. Daprà ◽  
P. Jansen ◽  
H. L. Bethlem ◽  
W. Ubachs ◽  
...  
Keyword(s):  
Electron Mass ◽  
Radio Telescopes ◽  
Mass Ratio
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