J. Bagdonaite, E.J. Salumbides, S.P. Preval, M.A. Barstow, J.D. Barrow, M.T. Murphy, W. Ubachs
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∼13000K) 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. © 2014 American Physical Society.
Department of Physics and Astronomy, LaserLaB, VU University, De Boelelaan 1081, HV Amsterdam, 1081, Netherlands; Department of Physics, University of San Carlos, Cebu City, 6000, Philippines; Department of Physics and Astronomy, University of Leicester, University Road, Leicester, LEI 7RH, United Kingdom; DAMTP, Centre for Mathematical Sciences, University of Cambridge, Cambridge, CB3 0WA, United Kingdom; Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Melbourne, 3122, VIC, Australia
