I study accreting supermassive black holes to measure how their activity is linked to their environment.
The main questions my work focuses on are:
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How and where do supermassive black holes grow and evolve?
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Is there significant interplay between their activity and their environments?
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How can the rate of AGN pairs inform us of the expected gravitational wave signal?
Selected papers are listed below, to view my full publication list please see my ADS Library here

Interacting SMBHs
The majority of my work focuses on finding pairs of supermassive black holes, and learning more about their preferential environments and evolution through mergers. I connect the X-ray activity of merging supermassive black holes with the optical and IR properties of their host galaxies.
Read more:
Gross, Chen, Foord+2023, ApJ
“Varstrometry for Off-nucleus and Dual sub-Kpc AGN (VODKA): Investigating the Nature of J0823+2418 at z=1.81: a Likely Lensed Quasar”
Chen, Xin, Foord+2023, Nature
“A Close Quasar Pair in a Disk-Disk Galaxy Merger at z = 2.17”
Koss (including Foord)+2023, ApJ
Foord+2022, ApJ
Foord+2021, ApJ
“AGN Triality of Triple Mergers: Multi-wavelength Classifications”
Foord+2021, ApJ
“AGN Triality of Triple Mergers: Detection of Faint X-ray Point Sources”
Foord+2020, ApJ
“A Second Look at 12 Candidate Dual AGNs using BAYMAX”
Foord+2019, ApJ
“A Bayesian Analysis of SDSS J0914+0853, a Low-Mass Dual AGN Candidate”
Foord+2017b, ApJ
“A Multi-wavelength Analysis of Binary-AGN Candidate PSO J334.2028+01.4075”

Resolving X-rays around black holes
Using statistical tools, I'm interested in better understanding the X-ray emission surrounding SMBHs. This includes high-redshift quasars, lensed quasars, and AGN in nucleated galaxies.
Read more:
Pacucci, Foord+2022, MNRAS
Baldassare, Stone, Foord+, 2022, ApJ
Napier, Foord+2020
“Extended X-ray emission from the z=4.26 radio galaxy 4C 63.20”
Foord+2017a, ApJ

Future X-ray Missions
I am interested and involved in future astrophysics missions focused on novel and ground-breaking measurements.
I am a Co-Investigator on the future mission probe concept AXIS, and I am leading the dual AGN science case.
I am a member of the Astrophysics Working Group of the LISA Consortium, where I am connecting large-scale AGN pair statistics to better understand future LISA measurements.