Environmental quenching – where interactions with other galaxies and/or the intra-cluster medium (ICM) suppress star formation in low-mass galaxies – has long been proposed as the primary driver to establish the red sequence for low-mass galaxies within clusters at low redshift (z<1). However, we still do not know whether these environmental quenching mechanisms are also active at higher redshifts in proto-cluster environments that have yet to fully virialize. In large part, this regime has remained unexplored due to observational limitations; however, the James Webb Space Telescope has recently opened a new window into the role of environmental quenching on low-mass (log(M_⋆/M_⊙)<9.5) galaxies at cosmic noon (2 < z < 3). Here, we use data from the JWST UNCOVER and MegaScience programs to directly probe the role of environmental quenching on low-mass galaxies in a newly-discovered z≈ 2.6 overdensity. Leveraging the deep imaging and R ∼ 15 spectrophotometry enabled by these JWST/NIRCam data, we analyze the stellar populations and inferred star formation histories (SFHs) of 20 low-mass (8.5<log(M_⋆/M_⊙)leq9.0) quiescent galaxies in the overdense environment and compare to a similar sample of 18 such galaxies in the field. The SFHs of quiescent galaxies in the proto-cluster and field across the entire probed stellar mass regime (8.5<log(M_⋆/M_⊙)leq11.0) are indistinguishable, demonstrating that the environment at cosmic noon is not yet accelerating quenching compared to the field. This is consistent with expectations that proto-clusters at z>2 have yet to virialize and develop a dense enough environment to efficiently quench low-mass galaxies.
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