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

Julija Bagdonaite ; M. Dapra ; P. Jansen ; H. L. Bethlem ; Wim Ubachs ; Sebastien Muller (Institutionen för rymd- och geovetenskap, Onsala rymdobservatorium) ; Christian Henkel ; Karl M. Menten
Physical Review Letters (0031-9007). Vol. 111 (2013), 23, p. 231101.
[Artikel, refereegranskad vetenskaplig]

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.



Denna post skapades 2013-12-09. Senast ändrad 2014-09-02.
CPL Pubid: 188714

 

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Institutioner (Chalmers)

Institutionen för rymd- och geovetenskap, Onsala rymdobservatorium

Ämnesområden

Fysik
Kosmologi

Chalmers infrastruktur

Onsala rymdobservatorium

 


Projekt

Denna publikation är ett resultat av följande projekt:


Advanced Radio Astronomy in Europe (RADIONET3) (EC/FP7/283393)