Prof. Keller’s NASA High-Priority Open Source Science grant, “Portable and Reproducible Initial Conditions for Galaxy Simulations”, has been selected by NASA for funding.

All galaxy simulation studies begin with initial conditions, which establish the starting point of particles or gas cells that then evolve over time. For cosmological zoom-in simulations, these initial conditions are drawn from large, collisionless cosmological volumes. Selecting these zoom-in initial conditions has typically been an ad-hoc procedure. This has led to a situation where initial conditions are often proprietary to individual groups, and even more critically, where the procedure for building these initial conditions is proprietary. This leads to duplicated effort and can make reproducing past results difficult-to-impossible. With this NASA HPOSS program, we will build a documented, open-source pipeline for building initial conditions and modifying them for future studies. This will aid in avoiding the uncertainty that arises from comparing different simulation studies beginning with different initial condition samples, which can obscure potential new discoveries.

This proposal aims directly at questions relevant to NASA’s FY2022 Strategic Objective 1.2 (“Understand the Sun, Solar System, and Universe”). With the development of an open-source, reproducible toolkit for constructing zoom-in galaxy initial conditions, we will further NASA’s Strategic Objective 1.3 (“Ensure NASA’s science data are accessible to all and produce practical benefits to society”). This toolkit will be a valuable pillar to support future work within our collaboration and within the broader community. With it, we will lower the labor requirements to construct new and modified initial conditions, and simplify direct comparisons of the same simulated galaxies with different simulation codes and choices of sub-grid models.