Turns out it's Double #GOALSJWST week!
UCI postdoc Marina Bianchin found what appears to be consistent with inflowing gas as evidence of self-regulating feeding-feedback process in the heart of NGC 7469 using JWST NIRspec data! 1/4
https://arxiv.org/abs/2308.00209
GOALS-JWST: Gas Dynamics and Excitation in NGC7469 revealed by NIRSpec
We present new JWST-NIRSpec IFS data for the luminous infrared galaxy NGC7469: a nearby (70.6Mpc) active galaxy with a Sy 1.5 nucleus that drives a highly ionized gas outflow and a prominent nuclear star-forming ring. Using the superb sensitivity and high spatial resolution of the JWST instrument NIRSpec-IFS, we investigate the role of the Seyfert nucleus in the excitation and dynamics of the circumnuclear gas. Our analysis focuses on the [Fe ii], H2, and hydrogen recombination lines that trace the radiation/shocked-excited molecular and ionized ISM around the AGN. We investigate the gas excitation through H2/Brγ and [Fe ii]/Pa\b{eta} emission line ratios and find that photoionization by the AGN dominates within the central 300 pc of the galaxy and together with a small region show ing signatures of shock-heated gas; these shock-heated regions are likely associated with a compact radio jet. In addition, the velocity field and velocity dispersion maps reveal complex gas kinematics. Rotation is the dominant feature, but we also identify non-circular motions consistent with gas inflows as traced by the velocity residuals and the spiral pattern in the Paα velocity dispersion map. The inflow is consistent with the mass outflow rate and two orders of magnitude higher than the AGN accretion rate. The compact nuclear radio jet has enough power to drive the highly ionized outflow. This scenario suggests that the inflow and outflow are in a self-regulating feeding-feedback process, with a contribution from the radio jet helping to drive the outflow.
Been missing #GOALSJWST results? Our GOALS team has been working hard on the rest of our #JWST ERS & Cyc1 data; the 1st of our new batch of papers is on arxiv today! Thomas Lai led the work on analyzing NIRSpec data of nearby LIRG NGC7469, focusing on 3.3um PAH...
https://arxiv.org/abs/2307.15169
GOALS-JWST: Small neutral grains and enhanced 3.3 micron PAH emission in the Seyfert galaxy NGC 7469
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 and
wavelength coverage of JWST /NIRSpec to study the 3.3 um neutral polycyclic
aromatic hydrocarbon (PAH) grain emission on ~60 pc scales. We find a clear
change in the average grain properties between the star-forming ring and the
central AGN. Regions in the vicinity of the AGN, with [NeIII]/[NeII]>0.25, tend
to have larger grain sizes and lower aliphatic-to-aromatic (3.4/3.3) ratios
indicating that smaller grains are preferentially removed by photo-destruction
in the vicinity of the AGN. We find an overall suppression of the total PAH
emission relative to the ionized gas in the central 1 kpc region of the AGN in
NGC 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 starburst
ring, possibly due to a variety of physical effects on sub-kpc scales,
including recurrent fluorescence of small grains or multiple photon absorption
by large grains. Finally, the IFU data show that while the 3.3 um PAH-derived
star 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 um
feature would be underestimated by a factor of two due to the deficit of PAHs
around the AGN, as might occur if a composite system like NGC 7469 were to be
observed at high-redshift.
Vivian U