The morphologies of quiescent galaxies provide insight into the physical processes that shut down star formation. Recent studies with JWST find that low mass quiescent galaxies have a lower Sérsic index and more disk-like morphologies relative to massive quenched galaxies, suggesting that the formation and quenching pathways of low and high mass galaxies are different. Owing to random viewing angles, a galaxy can have a range of observable axis ratios depending on its orientation. It is therefore necessary to consider the full distribution of axis ratios at a population level. Using JWST/NIRCam rest-optical imaging from the PRIMER survey, we analyze the intrinsic axis ratio distributions of 154 quiescent galaxies at 1<z<3 by considering pure populations (thin/thick disk, prolate, spheroidal) and linear combinations therein. We determine that more massive, older quiescent galaxies are mostly spheroid, whereas lower mass, younger quiescent galaxies are consistent with disky and prolate morphologies. These findings are well aligned with those inferred based on Sérsic index alone and are consistent with models where internal feedback drives quenching on the high mass end whereas environmental quenching is dominant in low mass galaxies. We are working on a similar analysis for star forming galaxies to assess our theories of quenching pathways for these two distinct populations.
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