<scp>dolphin</scp>: A Fully Automated Forward-modeling Pipeline Powered by Artificial Intelligence for Galaxy-scale Strong Lenses

Abstract Strong gravitational lensing is a powerful tool for probing the internal structure and evolution of galaxies, the nature of dark matter, and the expansion history of the Universe, among many other scientific applications. For almost all of these science cases, modeling the lensing mass distribution is essential. For that, forward modeling of imaging data to the pixel level is the standard method used for galaxy-scale lenses. However, the traditional workflow of forward lens modeling necessitates a significant amount of human investigator time, requiring iterative tweaking and tuning of the model settings through trial and error. An automated lens-modeling pipeline can substantially reduce the need for human investigator time. In this paper, we present dolphin , an automated lens-modeling pipeline that combines artificial intelligence with the traditional forward-modeling framework to enable full automation of the modeling workflow. dolphin uses a neural network model to perform visual recognition of the strong lens components, then autonomously sets up a lens model with appropriate complexity and fits the model with the modeling engine, lenstronomy . Thanks to the versatility of lenstronomy , dolphin can autonomously model both galaxy–galaxy and galaxy–quasar strong lenses.