Top row: color map of the velocity-integrated intensity of J = 1 → 0 transition of ¹³CO overlaid with contours of panel a, WISE 22 μm mid-IR continuum emission and (b) ATLASGAL870 μm continuum emission toward M8 E. Bottom row, panel c: color map of the velocity-integrated intensity of J = 1 → 0 transition of N₂H⁺ overlaid with ATLASGAL 870 μm dust continuum emission, and panel d: contours of the velocity-integrated intensity map of ¹²CO overlaid on the 8 μm PAH emission map. Position offsets are relative to the position of M8E-IR (marked with an asterisk) given in Sect. 2, and the ultracompact H II region, M8E-radio, at (α,δ)_J2000 = 18^h 04^m52^s8, −24°26′36′′ is represented by a black triangle. The ¹²CO and ¹³CO emission maps have their original resolutions of 22.5′′ and 23.5′′, respectively,the MIPSGAL 24 μm continuum emission has a resolution of 6′′, the ATLASGAL 870 μm continuum emission has a resolution of 18.2′′, and the GLIMPSE 8 μm continuum emission has a resolution of 0.6′′. The contour levels are 5 to 100% in steps of 10% for the MIPSGAL 24 μm (a) and the ATLASGAL 870 μm (b, c) overlays. For the GLIMPSE 8 μm (d) overlay, the contour levels are 10 to 100% in steps of 10%.