Novel Correlations between Diffuse Interstellar Bands and Optical Reddening

Abstract

Abstract The relatively new and expansive Apache Point Observatory Catalog of Optical Diffuse Interstellar Bands was analyzed to identify novel correlations between diffuse interstellar bands (DIBs) and optical reddening E(B − V), with a principal aim being to facilitate future identifications of the host molecular carriers. The following lines exhibit the highest Pearson r correlations in descending order (0.930 ≥ r ≥ 0.885), and are tied to DIBs featuring n ≥ 10 sightlines and possessing equivalent width uncertainties: λ (Å) ≃ 5236.27, 5793.24, 5797.18, 6449.27, 6795.26, 5948.87, 6113.22, 6860.02, 6059.34, 6520.74. Independent observations to confirm the preliminary trends are desirable, and extinction estimates could be subsequently inferred for targets by relying on longer-wavelength (NIR) photometric calibrations linked to a weighted subset of numerous DIBs. Lastly, several DIBs appear unassociated with E(B − V), thereby reaffirming that diverse carriers exist.