Sensitivity coefficients to $\alpha$-variation for fine-structure transitions in Carbon-like ions

Abstract

We calculate sensitivity coefficients to $\alpha$-variation for the fine-structure transitions (1,0) and (2,1) within ${}^3{P}_J[2s^{2}2p^2]$ multiplet of the Carbon-like ions C I, N II, O III, Na VI, Mg VII, and Si IX. These transitions lie in the far infrared region and are in principle observable in astrophysics for high redshifts z~10. This makes them very promising candidates for the search for possible $\alpha$-variation on a cosmological timescale. In such studies one of the most dangerous sources of systematic errors is associated with isotope shifts. We calculate isotope shifts with the help of relativistic mass shift operator and show that it may be significant for C I, but rapidly decreases along the isoelectronic sequence and becomes very small for Mg VII and Si IX.

5 pages

References in corpus (3)

• Strong Limit on a Variable Proton-to-Electron Mass Ratio from Molecules in the Distant Universe
• A new approach for testing variations of fundamental constants over cosmic epochs using FIR fine-structure lines
• Mid- and far-infrared fine-structure line sensitivities to hypothetical variability of the fine-structure constant