The properties of Polycyclic Aromatic Hydrocarbons in galaxies: constraints on PAH sizes, charge and radiation fields
نویسندگان
چکیده
Based on theoretical spectra computed using Density Functional Theory we study the properties of Polycyclic Aromatic Hydrocarbons (PAH). In particular bin-average PAH molecules with varying number carbons investigate how intensity mid-infrared emission bands, 3.3, 6.2, 7.7 and 11.3 microns, respond to changes in carbons, charge molecule, hardness radiation field that impinges molecule. We confirm 6.2/7.7 band ratio is a good predictor for size molecule (based present). also efficacy 11.3/3.3 trace note dependence this field. While can potentially be used molecular size, better understanding impact underlying 3.3 microns feature effect extinction should evaluated. The newly developed diagnostics are compared ratios measured variety galaxies observed Infrared Spectrograph board Spitzer Space Telescope. demonstrate probe conditions interstellar medium differentiate between environments encountered normal star forming Active Galactic Nuclei. Our work highlights immense potential observations James Webb Telescope will have our itself physical near far.
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2021
ISSN: ['0035-8711', '1365-8711', '1365-2966']
DOI: https://doi.org/10.1093/mnras/stab959