A search for varying fundamental constants using hertz-level frequency measurements of cold CH molecules (original) (raw)
ADS
;
- Hendricks, R. J. ;
- Tokunaga, S. K. ;
- Lewandowski, H. J. ;
- Kozlov, M. G. ;
- Henkel, Christian ;
- Hinds, E. A. ;
- Tarbutt, M. R.
Abstract
Many modern theories predict that the fundamental constants depend on time, position or the local density of matter. Here we develop a spectroscopic method for pulsed beams of cold molecules, and use it to measure the frequencies of microwave transitions in CH with accuracy down to 3 Hz. By comparing these frequencies with those measured from sources of CH in the Milky Way, we test the hypothesis that fundamental constants may differ between the high- and low-density environments of the Earth and the interstellar medium. For the fine structure constant we find Δα/α=(0.3±1.1) × 10-7, the strongest limit to date on such a variation of α. For the electron-to-proton mass ratio we find Δμ/μ=(-0.7±2.2) × 10-7. We suggest how dedicated astrophysical measurements can improve these constraints further and can also constrain temporal variation of the constants.
Publication:
Nature Communications
Pub Date:
October 2013
DOI:
arXiv:
Bibcode:
Keywords:
- Physics - Atomic Physics
E-Print:
8 pages, 3 figures