# WoU-MMA: Multi-messenger transients from magnetically arrested accretion onto supermassive black hole binaries

> **NSF 01002526DB NSF RESEARCH & RELATED ACTIVIT** · California Institute of Technology (CA) · $412,671

## Abstract

Merging supermassive black hole binaries (SMBHBs) are exciting sources for gravitational wave detections with space-based gravitational wave observatories and pulsar timing arrays. Since they will likely be surrounded by a gaseous accretion flow, they can also power multi-messenger transient emission before, during and after merger. This project will investigate a novel accretion regime that could give rise to new electromagnetic detection channels of SMBHBs and their merger. The researchers will investigate the magnetically arrested (MAD) accretion regime of a SMBHB, in which the black holes are embedded in a strong magnetic field regulating the accretion flow and leading to periodic magnetic flux eruptions into the accretion disk. This project will positively contribute to the training of the STEM workforce. The junior personnel on the project will learn analytic and problem-solving techniques, including computational methods and competence with standard quantitative analysis and programming tools, which will enhance their productivity in whatever future endeavors or careers they pursue.

These investigations will contribute to our understanding of future multi-messenger gravitational wave events of merging supermassive black hole binaries and their orbital evolution. This includes investigating a novel magnetically arrested (MAD) accretion regime for circumbinary accretion flows onto SMBHBs. In particular, the researchers will determine whether this regime influences the

## Key facts

- **NSF award ID:** 2508940
- **Awardee organization:** California Institute of Technology (CA)
- **SAM.gov UEI:** U2JMKHNS5TG4
- **PI:** Elias R Most
- **Primary program:** 01002526DB NSF RESEARCH & RELATED ACTIVIT
- **All programs:** Windows on the Universe (WoU), THEORETICAL & COMPUTATIONAL ASTROPHYSICS, OBSERVATIONAL ASTRONOMY
- **Estimated total:** $412,671
- **Funds obligated:** $412,671
- **Transaction type:** Standard Grant
- **Period:** 09/01/2025 → 08/31/2028

## Primary source

NSF Award Search: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2508940

## Citation

> US National Science Foundation, Award 2508940, WoU-MMA: Multi-messenger transients from magnetically arrested accretion onto supermassive black hole binaries. Retrieved via AI Analytics 2026-06-08 from https://api.ai-analytics.org/grant/nsf/2508940. Licensed CC0.

---

*[NSF Awards dataset](/datasets/nsf-awards) · CC0 1.0*
