Simulating Direct-Collapse Black Holes: Gravitational Waveform Predictions for LISA

Investigating direct-collapse black hole (DCBH) formation is crucial for understanding the massive black hole population in the early universe. DCBHs could be important gravitational wave sources for the Laser Interferometer Space Antenna (LISA), but only a few numerical waveforms and crude analytical estimates exist, reflecting our limited theoretical understanding of these systems. Increasing the number and accuracy of waveform predictions is essential to maximize the scientific output of future LISA detections.

We present a pipeline to study DCBH formation: starting with a collapsing region from a cosmological simulation, we perform a stellar evolution, followed by modeling black hole formation and gravitational wave signals using numerical relativity. We focus on the techniques and tools required at the final stage of this pipeline. These simulations will enable us to assess and improve LISA's detection and identification capabilities for these events.