Constraints on changes in fundamental constants from a cosmologically distant OH absorber or emitter.
We have detected the four 18 cm OH lines from the z approximaetely 0.765 gravitational lens toward PMN J0134-0931. The 1612 and 1720 MHz lines are in conjugate absorption and emission, providing a laboratory to test the evolution of fundamental constants over a large lookback time. We compare the HI and OH main line absorption redshifts of the different components in the z approximately 0.765 absorber and the z approximately 0.685 lens toward B0218 + 357 to place stringent constraints on changes in F triple-bond g(p)[alpha(2)/mu](1.57). We obtain [DeltaF/F] = (0.44 +/- 0.36(stat) +/- 1.0(sys)t) x 10(-5), consistent with no evolution over the redshift range 0 < z < or = 0.7. The measurements have a 2sigma sensitivity of [Deltaalpha/alpha] < 6.7 x 10(-6) or [Deltamu/mu] < 1.4 x 10(-5) to fractional changes in alpha and mu over a period of approximately 6.5 G yr, half the age of the Universe. These are among the most sensitive constraints on changes in mu.
Kanekar
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N
National Radio Astronomy Observatory, Socorro, New Mexico 87801, USA. nkanekar@aoc.nrao.edu
Carilli
C L
CL
Langston
G I
GI
Rocha
G
G
Combes
F
F
Subrahmanyan
R
R
Stocke
J T
JT
Menten
K M
KM
Briggs
F H
FH
Wiklind
T
T