Photometry of young stellar objects in Cepheus OB4

Studying the distribution and abundance of young stellar objects (YSOs) in these ionized bubbles can provide essential insight into the physical processes that shape their formation, allowing us to test competing models of star formation. In this work, we examined one such OB association, Cepheus OB4 (CepOB4)-a well-suited region for studying YSOs due to its Galactic location, proximity, and geometry.

We created a photometric catalog from Spitzer/Infrared Array Camera (IRAC) mosaics in bands 1 (3.6{mu}m) and 2 (4.5{mu}m). We supplemented the catalog with photometry from the Wide-field Infrared Survey Explorer, the Two Micron All Sky Survey, IRAC bands 3 (5.8{mu}m) and 4 (8.0{mu}m), MIPS 24{mu}m, and MMIRS near-infrared data. We used color-color selections to identify 821 YSOs, which we classified using the IR slope of the YSOs' spectral energy distributions, finding 67 Class I, 103 flat spectrum, 569 Class II, and 82 Class III YSOs.