Fig. 1.
Detection of cis-HCOOH towards the FUV-illuminated edge of the Orion Bar. Left: 13CO J = 3 → 2 integrated emission image with a HPBW of 8′ obtained with the IRAM-30 m telescope (Cuadrado et al. in prep.). The cyan contour marks the position of neutral cloud boundary traced by the O i 1.317 µm fluorescent line emission (in contours from 3 to 7 by 2 × 10−4 erg s−1 cm−2 sr−1; Walmsley et al. 2000). Right: Cis- and trans-HCOOH stacked spectra towards the observed positions.