EDIBLES survey. VI.

We selected 31 strong DIBs, 7 atomic and 5 molecular lines to focus our search on. We carefully considered various systematic effects and used a robust Bayesian quantitative test to establish which of these absorption features could display significant variations. While systematic effects greatly complicate our search, we find evidence for variations in the profiles of the {lambda}{lambda}4727 and 5780 DIBs in a few sightlines.

Toward HD 167264, we find a new CaI cloud component that appears and becomes stronger after 2008. The same sightline furthermore displays marginal, but systematic changes in the column densities of the atomic lines originating from the main cloud component in the sightline. Similar variations are seen toward HD 147933.

Our high-quality spectroscopic observations in combination with archival data show that it is possible to probe interstellar time variations on time scales of typically a decade. Despite the fact that systematic uncertainties as well as the generally somewhat lower quality of older data complicate matters, we can conclude that time variations can be made visible, both in atomic lines and DIB profiles for a few targets, but that generally, these features are stable along many lines of sight.

We present this study as an archival baseline for future comparisons, bridging longer periods.