Abstract

We exploit a new sample of around 400 bright dusty galaxies from the Atacama Large Millimeter/submillimeter Array (ALMA) CHAMPS Large Program, together with the rich JWST multiband data products in the COSMOS field, to explore and validate new selection methods for identifying dusty star-forming galaxies (DSFGs). Here we present an effective empirical selection criterion based on a newly defined parameter: I-star equivalent to log(10)(M-star)xlog(10)(SFR) . Incorporating the m277W - m444W color as a second parameter further improves the purity of the selection. We then apply this method to the COSMOS2025 catalog to search for fainter dusty galaxy candidates below the ALMA CHAMPS detection limit and, through a stacking technique, identify a population of high-redshift DSFG candidates with an average flux density of S-1.2mm approximate to 150 mu Jy and a space density of similar to 6 x 10(-6) Mpc(-3). Three of these galaxies have been spectroscopically confirmed at z(spec) = 7.20, 5.85, and 5.04. This faint population seems to have been missed by most of the previous submillimeter/millimeter surveys and ground- and space-based UV-near-IR observations. We then show evidence of a possible evolutionary connection between the z > 10 UV-bright galaxies recently discovered by JWST, the faint dusty z approximate to 6-8 galaxies identified here, and the population of z approximate to 3-5 massive quiescent galaxies; all of them are potentially linked as progenitor-descendant populations based on their abundance, redshifts, and stellar masses. Future spectroscopic campaigns will be essential to confirm the redshifts and physical properties of these massive, faint, high-redshift DSFG candidates.