AGN and their outflows: probing fragmentation and survival of polycyclic aromatic hydrocarbons
Abstract
It is widely accepted that the short-lived phase of active galactic nuclei (AGN) and their winds can have a drastic impact on the interstellar medium of most galaxies. Large amounts of dust and gas are located at the central regions of AGN, where optical wavelengths are heavily affected by extinction making the mid-infrared (MIR) the ideal spectral range to investigate these inner regions. Polycyclic Aromatic Hydrocarbons (PAHs) are carbon-based molecules, which are responsible for strong MIR emission features. PAH emission is potentially one of the best tools to trace star-forming (SF) activity in the heavily dust-extinguished and hostile environments of AGN. However, our limited knowledge of the effect of the radiation field, outflows and shocks on them is a shortcoming of this approach. AGN and their winds offer unique environments to investigate not only the fragmentation/survival of PAHs but also the mechanism for transporting them in their winds.
Our proposal builds on targets with existing/scheduled MRS observations and for which we request 3-5 micron NIRSpec observations. NIRSpec+MRS data are essential for reaching our goals. The first goal is to fully characterize the properties of PAHs in AGN and their winds. For this, the 3.3+3.4 micron PAH proposed observations are crucial to put strong constraints on the fragmentation and survival of PAHs. The second goal is to understand AGN feedback mechanisms. To do so, once the PAH propesties are fully characterize, we will establish which PAHs are best to trace SFR activity in active galaxies. The proposed study is fundamental since PAH bands are routinely used to measure SF activity in near and far SF galaxies and AGN.- Publication:
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JWST Proposal. Cycle 3
- Pub Date:
- February 2024
- Bibcode:
- 2024jwst.prop.5017G