SIMBAD references

2017MNRAS.471.2143L - Mon. Not. R. Astron. Soc., 471, 2143-2150 (2017/October-3)

[C I], [C II] and CO emission lines as a probe for α variations at low and high redshifts.


Abstract (from CDS):

The offsets between the radial velocities of the rotational transitions of carbon monoxide and the fine structure transitions of neutral and singly ionized carbon are used to test the hypothetical variation of the fine structure constant, α. From the analysis of the [C I] and [C II] fine structure lines and low J rotational lines of 12CO and 13CO, emitted by the dark cloud L1599B in the Milky Way disc, we find no evidence for fractional changes in α at the level of |Δα/α| < 3 x 10–7. For the neighbouring galaxy, M33, a stringent limit on Δα/α is set from observations of three H II zones in [C II] and CO emission lines: |Δα/α| < 4 x 10–7. Five systems over the redshift interval z = 5.7-6.4, showing CO J = 6-5, J = 7-6 and [C II] 158 µm emission, yield a limit on |Δα/α| < 1.3 x 10–5. Thus, a combination of the [C I], [C II] and CO emission lines turns out to be a powerful tool for probing the stability of the fundamental physical constants over a wide range of redshifts not accessible to optical spectral measurements.

Abstract Copyright: © 2017 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society

Journal keyword(s): methods: observational - techniques: spectroscopic - galaxies: individual: M33 - cosmology: observations - radio lines: ISM - radio lines: ISM

Simbad objects: 21

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2017MNRAS.471.2143L and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact