Ultra faint edge on galaxies: standard and alternative gravity explorations

Abstract

Recently, Bizyaev et. al. (2021) conducted the first modeling of rotation curves for 153 ultra-faint, edge-on galaxies using the 3.5 m telescope at the Apache Point Observatory. These models derived high resolution rotation curves for 20 galaxies of various sizes and spiral morphologies, making new estimates of the optical scale lengths. Using the derived models, in this work we make the first fits to the rotation curves using alternative gravity, namely conformal gravity, Modified Newtonian Dynamics (MOND) and more. A robust analysis is shown including the derived rotation curve fits to the alternative gravity models, along with how the models account for empirical phenomena such as the Baryonic Tully Fisher relation and the Radial Acceleration Rule. This data is not only modern, but unique in that certain galaxies are shown to be able to be fit by standard gravity alone without dark matter.