The Discovery of Ancient Relics in an Evolved Galaxy at z=2.5

Abstract

With the recent discovery of The Sparkler'', JWST has opened up uncharted parameter space in the distant universe: remarkable high resolution views of ancient globular cluster (GC) candidates. There exists another fascinating galaxy in the Abell 2744 lensing cluster at even higher redshift that is littered with compact red and blue star-forming complexes - The Relic’’. Here, we will present the discovery of the Relic, a bright, quenched galaxy at z=2.5, existing merely a few billion years after the Big Bang. These compact star-forming complexes are potential GC candidates, with the red ones consistent with ancient relics with formation times as early as z~10, while the blue ones may be caught early in their formation. If these candidates survive to the present day, they would have ages ranging from 11 to 13 billion years. Based on a photometric analysis that includes recently acquired ultra-deep medium-band photometry, we present an overview of the stellar population properties of these GC candidates as a function of their projected distance, using this to assess their probabilities of surviving relative to being disrupted and contributing to bulge formation.