Spatial analysis of PAH molecules in the Pillars of Creation using JWST

TL;DR

This study uses JWST imaging to produce the first spatial maps of PAH size and ionization in the Pillars of Creation, revealing how local radiation and density influence dust properties in star-forming regions.

Contribution

It provides the first spatially resolved maps of PAH ionization and size in the Pillars of Creation, linking PAH properties to local environmental conditions.

Findings

PAH population varies with local radiation and density.

Regions with intense radiation have larger, neutral PAHs.

Estimated electron density in the cloud based on PAH analysis.

Abstract

I present a spatially resolved analysis of the polycyclic aromatic hydrocarbon (PAH) population in the Pillars of Creation within the Eagle Nebula (M16) using the James Webb Space Telescope's (JWST) Mid Infrared Instrument (MIRI) and Near Infrared Camera (NIRCam) imaging. By using mid infrared PAH sensitive bands, I derive resolved maps of PAH size and ionization state across the pillars and connect these directly to variations in the radiation field and gas structure. I present the first spatial maps of PAH ionization and size in the Pillars of Creation. The analysis reveals clear internal gradients that show the PAH population is strongly shaped by local conditions within the cloud, such as the local radiation intensity and orientation of the nebular structure. The intensely radiated regions show a neutral and large PAH population, possibly due to electron recombination in these regions. I measure a mean PAH size of 198 carbon atoms with an error bar of 1.22 for M16 and use the resolved emission structure to obtain a first-order estimate of the electron density in the molecular cloud. These results provide direct evidence that PAH properties in M16 are governed by the interplay between radiation and density on sub-cloud scales, demonstrating the power of JWST imaging to probe dust processing in star-forming regions.