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Abstract We present a 3D shape analysis of both dark matter (DM) and stellar matter (SM) in simulated dwarf galaxies to determine whether stellar shape traces DM shape. Using 80 central and satellite dwarf galaxies from three simulation suites (“Marvelous Massive Dwarfs,” “Marvelous Dwarfs,” and the “DC Justice League”) spanning stellar masses of 10⁶–10¹⁰M_⊙, we measure 3D shapes through the moment of inertia tensor at twice the effective radius to derive axis ratios (C/AandB/A) and triaxiality. We find that stellar shape does follow DM halo shape for our dwarf galaxies. However, the presence of a stellar disk in more massive dwarfs (M_* ≳ 10^7.5M_⊙) pulls the distribution of stellarC/Aratios to lower values, while in lower-mass galaxies the gravitational potential remains predominantly shaped by DM. Similarly, stellar triaxiality generally tracks DM triaxiality, with this relationship being particularly strong for nondisky galaxies and weaker in disky systems. These correlations are reinforced by strong alignment between the SM and DM axes, particularly in disk galaxies. Further, we find no detectable difference in either SM or DM shapes when comparing two different supernova feedback implementations, demonstrating that shape measurements are robust to different implementations of baryonic feedback in dwarf galaxies. We also observe that a dwarf galaxy’s shape is largely unperturbed by recent mergers. This comprehensive study demonstrates that stellar shape measurements can serve as a reliable tool for inferring DM shapes in dwarf galaxies. 

First light observations of the 280-GHz instrument module of the Fred Young Submillimeter Telescope in the CCAT Collaboration are expected in 2026. The focal plane of this module will consist of three superconducting microwave kinetic inductance detector (MKID) arrays: two aluminum-based arrays and one titanium nitride array with a similar layout. We have designed, microfabricated, assembled, and characterized a large-format aluminum-based MKID array. The responsivity of the detectors matches design expectation and scales at various optical loading levels as expected for aluminum. We have determined the internal quality factors and optical efficiency of the detectors, feedhorn beam shape, and the detector band pass. The detectors are photon noise limited with the majority of the noise being white photon noise down to 1 Hz. The array matches simulated expectations and is ready for sensitive astronomical observations for CCAT. Certain commercial equipment, instruments, or materials are identified in this paper to specify the experimental procedure adequately. Such identification is not intended to imply recommendation or endorsement by NIST, nor is it intended to imply that the materials or equipment identified are necessarily the best available for the purpose.