Limits on a Gravitational Field Dependence of the Proton-Electron Mass Ratio from H2 in White Dwarf Stars
Abstract
Spectra of molecular hydrogen (H2) are employed to search for a possible proton-to-electron mass ratio (μ) dependence on gravity. The Lyman transitions of H2, observed with the Hubble Space Telescope towards white dwarf stars that underwent a gravitational collapse, are compared to accurate laboratory spectra taking into account the high temperature conditions (T ∼13 000 K) of their photospheres. We derive sensitivity coefficients Ki which define how the individual H2 transitions shift due to μ dependence. The spectrum of white dwarf star GD133 yields a Δμ/μ constraint of (-2.7±4.7stat±0.2syst)×10-5 for a local environment of a gravitational potential ϕ∼104 ϕEarth, while that of G29-38 yields Δμ/μ =(-5.8±3.8stat±0.3syst)×10-5 for a potential of 2×104 ϕEarth.
- Publication:
-
Physical Review Letters
- Pub Date:
- September 2014
- DOI:
- 10.1103/PhysRevLett.113.123002
- arXiv:
- arXiv:1409.1000
- Bibcode:
- 2014PhRvL.113l3002B
- Keywords:
-
- 33.20.Lg;
- 06.20.Jr;
- 14.20.Dh;
- 97.20.Rp;
- Ultraviolet spectra;
- Determination of fundamental constants;
- Protons and neutrons;
- Faint blue stars white dwarfs degenerate stars nuclei of planetary nebulae;
- General Relativity and Quantum Cosmology;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 5 pages, 3 figures. Accepted by PRL