Ultralight dark matter simulations and stellar dynamics: Tension in dwarf galaxies for <inline-formula><mml:math><mml:mrow><mml:mi>m</mml:mi><mml:mo><</mml:mo><mml:mn>5</mml:mn><mml:mo>×</mml:mo><mml:msup><mml:mrow><mml:mn>10</mml:mn></mml:mrow><mml:mr
We present numerical simulations of dark matter and stellar dynamics in ultralight dark matter halos tailored to mimic dwarf galaxies. An important effect we observe is the dynamical evolution of the stellar half-light radius and velocity dispersion, which makes previous equilibrium models significantly incomplete. Based on half-light radius
The ALMA survey to Resolve exoKuiper belt Substructures (ARKS): VI. Asymmetries and offsets
Context. Asymmetries in debris discs provide unique clues to understand the evolution and architecture of planetary systems. Previous studies of debris discs at (sub)millimetre wavelengths have suggested the presence of asymmetries in a wide variety of systems, yet the lack of sufficiently sensitive high-resolution observations means that the
The ALMA survey to Resolve exoKuiper belt Substructures (ARKS): VII. Optically thick gas with broad CO gaussian local line profiles in the HD 121617 disc
Context. CO gas has been detected in ~20 debris discs, typically classified as CO-poor or CO-rich. We present observations of the CO-rich HD 121617 debris disc as part of the ALMA survey to Resolve exoKuiper belt Substructures (ARKS). Aims. We model local CO line profiles in the HD 121617 debris disc to investigate optical depth, CO mass, and