Interstellar extinction toward symbiotic stars

TL;DR

This study estimates interstellar extinction toward seven symbiotic stars using diffuse interstellar bands in high-resolution spectra, providing measurements consistent with galactic extinction values.

Contribution

It introduces a method of using DIBs at specific wavelengths to measure interstellar extinction toward symbiotic stars.

Findings

Extinction values range from 0.30 to 1.55 in E_{B-V}

Results agree with known galactic extinction estimates

Provides extinction measurements for seven symbiotic stars

Abstract

Using diffuse interstellar bands (DIBs) at 5780 A, 5797 A and 6613 A, visible in the high resolution spectra, and measuring their equivalent widths, we estimate the interstellar extinction toward seven symbiotic stars. We find $E_{B-V}$= $1.28 \pm 0.10$ for AS 289, $E_{B-V}$= $1.55 \pm 0.10$ for BI Cru, $E_{B-V}$= $0.63 \pm 0.10$ for HD330036, $E_{B-V}$= $0.33 \pm 0.05$ for V2756 Sgr, $E_{B-V}$= $0.30 \pm 0.05$ for V2905 Sgr, $E_{B-V}$= $1.52 \pm 0.11$ for V417 Cen, $E_{B-V}$= $0.81 \pm 0.10$ for PN Sa 3-22. The derived values are in agreement with the extinction through the Galaxy.