Multiscale Modelling of Galaxy Collisions with Integrated Resistive MHD and Stellar Feedback

Abstract: Predicting the relative roles of gravitational collapse and stellar feedback in star formation within extreme, low-density environments—such as the tidal tails produced by galaxy mergers—remains a fundamental challenge. These environments provide unique natural laboratories for testing star formation theories under conditions analogous to the early universe. However, existing models often fail to reconcile large-scale gravitational dynamics with localized feedback processes in such diffuse media. To bridge this gap, a reproducible, open-sciencebased theoretical framework is presented that integrates public, multi-wavelength observational datasets with high-resolution **resistive magnetohydrodynamic (MHD)** simulations. Our methodology is built on archival data from three flagship observatories: the James Webb Space Telescope (JWST), which is used to study young stellar populations and newly formed clusters. This telescope provides high-resolution infrared imaging and spectroscopy, enabling precise measurements of stellar ages, masses, and dust extinction. - Atacama Large Millimetre/submillimetre Array (ALMA): used to trace cold molecular gas and analyze kinematic structures. These public datasets are used as quantitative constraints in resistive magnetohydrodynamic (MHD) simulations that incorporate magnetic fields, radiative cooling, sub-grid star formation, and stellar feedback, ensuring that the simulation results remain consistent with observational reality. Using the open-source code **PLUTO**, we model the formation of tidal structures while resolving key plasma physics, including **localized resistivity** to capture magnetic reconnection effects. “Synthetic observations” are directly generated from simulation outputs using radiative transfer post-processing, enabling point-by-point comparison with real data. To rigorously quantify agreement between model and observation, we implement a **Bayesian inference framework** that propagates observational uncertainties and yields posterior constraints on key parameters (e.g., magnetic field strength, feedback coupling efficiency). Through this integrated pipeline, the aim is to determine whether star formation efficiency in lowdensity tails is regulated by gravitational confinement from tidal compression or by localized feedback. Expected outcomes include quantitative estimates of virial stability parameters for observed gas complexes, spatial correlation analyses to gauge feedback coupling efficiency, and statistically robust constraints on uncertain model parameters. This framework is fully reproducible: all data are public, simulation codes are opensource, and analysis scripts will be archived with a DOI upon acceptance. By transparently linking theory and observation, this approach provides a methodological blueprint for studying star formation in interacting systems, with direct implications for galaxy evolution models and future observational strategies.