Robust Constraint on a Drifting Proton-to-Electron Mass Ratio at z=0.89 from Methanol Observation at Three Radio Telescopes
Journal article, 2013

A limit on a possible cosmological variation of the proton-to-electron mass ratio μ is derived from methanol (CH3OH) absorption lines in the benchmark PKS1830–211 lensing galaxy at redshift z=0.89 observed with the Effelsberg 100-m radio telescope, the Institute de Radio Astronomie Millimétrique 30-m telescope, and the Atacama Large Millimeter/submillimeter Array. Ten different absorption lines of CH3OH covering a wide range of sensitivity coefficients Kμ are used to derive a purely statistical 1σ constraint of Δμ/μ=(1.5±1.5)×10−7 for a lookback time of 7.5 billion years. Systematic effects of chemical segregation, excitation temperature, frequency dependence, and time variability of the background source are quantified. A multidimensional linear regression analysis leads to a robust constraint of Δμ/μ=(−1.0±0.8stat±1.0sys)×10−7.

Author

Julija Bagdonaite

M. Dapra

P. Jansen

H. L. Bethlem

Wim Ubachs

Sebastien Muller

Chalmers, Earth and Space Sciences, Onsala Space Observatory

Christian Henkel

K. M. Menten

Physical Review Letters

0031-9007 (ISSN) 1079-7114 (eISSN)

Vol. 111 23 231101-

Advanced Radio Astronomy in Europe (RADIONET3)

European Commission (FP7), 2012-01-01 -- 2015-12-31.

Subject Categories

Physical Sciences

Astronomy, Astrophysics and Cosmology

Roots

Basic sciences

Infrastructure

Onsala Space Observatory

DOI

10.1103/PhysRevLett.111.231101

More information

Created

10/7/2017