Electron density and carriers of the diffuse interstellar bands
نویسندگان
چکیده
We have used the ionisation equilibrium equation to derive the electron density in in-terstellar clouds in the direction to 13 stars. A linear relation was found, that allows the determination of the electron density from the Mg I and Mg II column densities in interstel-lar medium. The comparison of normalised equivalent width of 12 DIBs with the electron density shows that the DIBs equivalent width do not change with varying electron density. Therefore the DIBs carriers (1) can be observed only in one ionisation stage, or (2) the DIBs are arising in cloud regions (cores or cloud coronas) for which we can not determine the electron density.
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