0 Assigned ID: 3761 ----- Attempting Submission 1 (Fri Mar 25 23:56:33 GMT 2022) ----- ----- Attempting Submission 2 (Sun Mar 27 11:39:53 GMT 2022) ----- Observations of galaxy-scale strong gravitational lenses have been used to put constraints on dark matter physics. It is now widely recognized that line-of-sight structures between the source and the observer play a significant role in perturbing lensed images, hence making multi-plane lensing a necessary part of any lens analysis. We propose here to utilize a freshly proposed approach that simplifies the multiplane nature of the lensing problem to an "effective" single mapping between the source and image planes to constrain dark matter. This mapping is fully characterized by two "effective" lensing potentials encompassing the complete structure of the deflection field. We propose to make detailed predictions for the statistical properties of these two potentials and their corresponding correlation function anisotropies in well-motivated dark matter theories. Since line-of-sight structure and main-lens substructure contribute differently to each potential, this method has the potential to distinguish these two contributions from one another, potentially improving the constraint on dark matter from strong lensing significantly. We also propose to further develop a likelihood framework to assess the sensitivity of mock data to anisotropic signatures, hence laying the groundwork for a future archival proposal to perform an in-depth study using past HST data. We will also perform forecasts for how future observations could separately constrain observables and what the resulting constraints on dark matter physics would be. Prof. Cyr-Racine has a wide expertise in studying how dark matter physics affects the assembly of the structure in our Universe. In particular, he has studied the impact of dark matter interactions taking place in the early Universe on the halo mass function and the inner properties of halos. Cyr-Racine also has broad expertise in studying the statistical impact of small dark matter structure on strongly lensed images. He has performed detailed forecasts of the reach of HST in constraining the small-scale power spectrum and developed a software package to carry out these power spectrum forecasts. Mr. Dhanasingham is a Ph.D. candidate at the University of New Mexico and an expert on numerical gravitational lensing. He is the lead developer of the effective multiplane lensing approach, and he has written software to study multiplane lensing and compute various correlation function of the deflection fields. Large Scale Structure of the Universe 0 Regular false false false true false false SUPPORTED