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We present James Webb Space Telescope (JWST) Near Infrared Spectrograph(NIRSpec) integral-field spectroscopy of the nearby luminous infrared galaxy,NGC 7469. We take advantage of the high spatial/spectral resolution andwavelength coverage of JWST /NIRSpec to study the 3.3 um neutral polycyclicaromatic hydrocarbon (PAH) grain emission on ~60 pc scales. We find a clearchange in the average grain properties between the star-forming ring and thecentral AGN. Regions in the vicinity of the AGN, with [NeIII]/[NeII]>0.25, tendto have larger grain sizes and lower aliphatic-to-aromatic (3.4/3.3) ratiosindicating that smaller grains are preferentially removed by photo-destructionin the vicinity of the AGN. We find an overall suppression of the total PAHemission relative to the ionized gas in the central 1 kpc region of the AGN inNGC 7469 compared to what has been observed with Spitzer on 3 kpc scales.However, the fractional 3.3 um to total PAH power is enhanced in the starburstring, possibly due to a variety of physical effects on sub-kpc scales,including recurrent fluorescence of small grains or multiple photon absorptionby large grains. Finally, the IFU data show that while the 3.3 um PAH-derivedstar formation rate (SFR) in the ring is 8% higher than that inferred from the[NeII] and [NeIII] emission lines, the integrated SFR derived from the 3.3 umfeature would be underestimated by a factor of two due to the deficit of PAHsaround the AGN, as might occur if a composite system like NGC 7469 were to beobserved at high-redshift.

GOALS-JWST: Small neutral grains and enhanced 3.3 micron PAH emission in the Seyfert galaxy NGC 7469