The Accretion Explorer Interferometer (AEI) Phase I NASA Innovative Advanced Concepts Final Report

Kimberly A. Weaver; Jenna M. Cann; Kenneth Carpenter; Maurice Leutenegger; Takashi Okajima; Scott Rohrbach; Liz Matson; Craig Stevens; George Bussey; Jean-Etienne Dongmo; David Kim; Jess Lewis; Khashayar Parsay; Sharon Peabody; Alison Rao; Sara Riall; Marta Shelton; Kan Yang; Isabella Carlton; Webster Cash; Kaylee DeGennaro; Emma Kleiner; John Krizmanic; Erini Lambrides; Miranda McCarthy; Jeffrey McKaig; Atul Mohan; Teresa Monsue; Ryan Pfeifle; Mainak Singha; Melville Ulmer; Laura D. Vega; Kelly E. Whalen

arXiv · 2609.03159

The Accretion Explorer Interferometer (AEI) Phase I NASA Innovative Advanced Concepts Final Report

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Abstract

We must create superb X-ray images to understand the detailed physical processes behind some of the most powerful astronomical objects. The need to achieve this capability has been known for decades. But as time proceeds, X-ray astronomy falls further behind other wavebands that are steadily increasing their imaging capacity. Radio astronomy in particular has reached an angular resolution on the order of micro arcseconds via aperture synthesis interferometry, using the interference of electromagnetic waves from many small telescopes together to simulate having a much larger telescope. Developing an equivalent high-resolution capability in the X-ray band would be a game changer for high-energy astrophysics. We will understand how supermassive black holes grow and evolve. We will learn what powers astrophysical jets. We will learn how young, active stars affect the habitability of their planets. Technologically, our NIAC study has shown that the Accretion Explorer Interferometer (AEI) concept, unlike the original MAXIM concept, is more feasible in operation, being only 2 km long, versus approximately 450 km. Our study has also shown that satellite station keeping is possible, leveraging from LISA pathfinder technology, and using large mirror flats plus an X-ray beamsplitter for enabling technology is feasible.

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Kimberly A. Weaver, Jenna M. Cann, Kenneth Carpenter, Maurice Leutenegger, Takashi Okajima, Scott Rohrbach, Liz Matson, Craig Stevens, George Bussey, Jean-Etienne Dongmo, David Kim, Jess Lewis, Khashayar Parsay, Sharon Peabody, Alison Rao, Sara Riall, Marta Shelton, Kan Yang, Isabella Carlton, Webster Cash, Kaylee DeGennaro, Emma Kleiner, John Krizmanic, Erini Lambrides, Miranda McCarthy, Jeffrey McKaig, Atul Mohan, Teresa Monsue, Ryan Pfeifle, Mainak Singha, Melville Ulmer, Laura D. Vega, Kelly E. Whalen. 2026-09-02. The Accretion Explorer Interferometer (AEI) Phase I NASA Innovative Advanced Concepts Final Report. https://arxiv.org/abs/2609.03159

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