GOALS-JWST: NIRCam and MIRI Imaging of the Circumnuclear Starburst Ring in NGC 7469
Inami, Hanae; Böker, Torsten; Kemper, Francisca; Aalto, Susanne; Hayward, Christopher C.; Larson, Kirsten L.; Linden, S. T.; Bohn, Thomas; Armus, Lee; Murphy, Eric J.; Malkan, Matthew A.; Stierwalt, Sabrina; Brown, Michael J. I.; Evans, Aaron S.; U, Vivian; Howell, Justin H.; Sanders, David; van der Werf, Paul P.; Surace, Jason; Rich, Jeffrey A.; Privon, George C.; Charmandaris, Vassilis; Law, David; Song, Yiqing; Appleton, Philip; Medling, Anne M.; Iwasawa, Kazushi; Marshall, Jason; Mazzarella, Joseph M.; Lai, Thomas; Barcos-Munoz, Loreto; Diaz-Santos, Tanio; Hoshioka, Shunshi
Japan, Greece, Cyprus, United States, Australia, Sweden, Spain, Netherlands
Abstract
We present James Webb Space Telescope (JWST) imaging of NGC 7469 with the Near-Infrared Camera and the Mid-InfraRed Instrument. NGC 7469 is a nearby, z = 0.01627, luminous infrared galaxy that hosts both a Seyfert Type-1.5 nucleus and a circumnuclear starburst ring with a radius of ~0.5 kpc. The new near-infrared (NIR) JWST imaging reveals 66 star-forming regions, 37 of which were not detected by Hubble Space Telescope (HST) observations. Twenty-eight of the 37 sources have very red NIR colors that indicate obscurations up to A v ~ 7 and a contribution of at least 25% from hot dust emission to the 4.4 μm band. Their NIR colors are also consistent with young (<5 Myr) stellar populations and more than half of them are coincident with the mid-infrared (MIR) emission peaks. These younger, dusty star-forming regions account for ~6% and ~17% of the total 1.5 and 4.4 μm luminosity of the starburst ring, respectively. Thanks to JWST, we find a significant number of young dusty sources that were previously unseen due to dust extinction. The newly identified 28 young sources are a significant increase compared to the number of HST-detected young sources (4-5). This makes the total percentage of the young population rise from ~15% to 48%. These results illustrate the effectiveness of JWST in identifying and characterizing previously hidden star formation in the densest star-forming environments around active galactic nuclei (AGN).