Young Stellar Objects in NGC 346: A JWST NIRCam/MIRI Imaging Survey

Abstract

We present a JWST imaging survey with NIRCam and MIRI of NGC 346, the brightest star-forming region in the Small Magellanic Cloud. By combining aperture and point-spread function photometry of 11 wavelength bands across these two instruments, we have detected more than 200,000 unique sources. Using a near-infrared color analysis, we observe various evolved and young populations, including 196 young stellar objects (YSOs) and pre-main-sequence stars suitable for forthcoming spectroscopic studies. We expand upon this work, creating mid-infrared color–magnitude diagrams and determining color cuts to identify 833 reddened sources which are YSO candidates. We observe that these candidate sources are spatially associated with regions of dusty, filamentary nebulosity. Furthermore, we fit model YSO spectral energy distributions to a selection of sources with detections across all of our MIRI bands. We classify with a high degree of confidence 23 YSOs in this sample and estimate their radii, bolometric temperatures, luminosities, and masses. We detect YSOs approaching 1 M ⊙, the lowest-mass extragalactic YSOs confirmed to date.