Characterizing spatial variations of PAH emission in the reflection nebula NGC 1333

ABSTRACT Infrared emission features at 3.3, 6.2, 7.7, 8.6, and 11.2 µm, attributed to polycyclic aromatic hydrocarbons (PAHs), show variations in relative intensity, shape, peak position. These depend on the physical conditions of photodissociation region (PDR) which strong PAH arises but their relationship has yet be fully quantified. We aim better calibrate response species environment using observations with matching apertures spatial resolution. present from Field-Imaging Far-Infrared Line Spectrometer onboard Stratospheric Observatory for Astronomy gas cooling lines [O i] 63, 146 µm [C ii] 158 reflection nebula NGC 1333 use archival dust continuum Photodetector Array Camera (PACS) Herschel. employ PDR modelling derive compare these characteristics as observed Spitzer. find distinct various spectral components. conclude that ionic bands (6.2, 11.0) 7–9 are due multiple subpopulations plateaus perched top. The 6–9 exhibits a significant change behaviour between irradiated diffuse outskirts, confirming arise different underlying molecular properties. promising relationships ratios far-ultraviolet radiation field strength no clear correlations ionization parameter.