The high energy X-ray probe (HEX-P): the future of hard X-ray dual AGN science

• DOI: 10.3389/fspas.2024.1304652
• Publication Date: 2024-05-20T08:33:51Z
• Authors: Ryan W. Pfeifle; Peter G. Boorman; Kimberly A. Weaver; Johannes Buchner; Francesca Civano; Kristin Madsen; Daniel Stern; Núria Torres-Albà; Emanuele Nardini; Claudio Ricci; Stefano Marchesi; D. R. Ballantyne; Dominic Sicilian; Chien-Ting Chen; Elias Kammoun; Ryan C. Hickox; Javier A. García; Labani Mallick
• Keywords: active galactic nucleus; galaxy merger; Astronomy; Galaxy Merger; Geophysics. Cosmic physics; FOS: Physical sciences; QB1-991; 7. Clean energy; 01 natural sciences; x-ray astronomy; Active galactic nucleus; Galaxy interaction; 0103 physical sciences; Instrumentation and Methods for Astrophysics (astro-ph.IM); High Energy Astrophysical Phenomena (astro-ph.HE); QC801-809; dual AGN; Dual AGN; Astrophysics - Astrophysics of Galaxies; galaxy interaction; 13. Climate action; active galactic nucleus; dual AGN; galaxy interaction; galaxy merger; x-ray astronomy; [PHYS.PHYS.PHYS-INS-DET] Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]; Astrophysics of Galaxies (astro-ph.GA); [PHYS.ASTR] Physics [physics]/Astrophysics [astro-ph]; Astrophysics - High Energy Astrophysical Phenomena; Astrophysics - Instrumentation and Methods for Astrophysics

A fundamental goal of modern-day astrophysics is to understand the connection between supermassive black hole (SMBH) growth and galaxy evolution. Merging galaxies offer one most dramatic channels for evolution known, capable driving inflows gas into galactic nuclei, potentially fueling both star formation central SMBH activity. Dual active nuclei (dual AGNs) in late-stage mergers with nuclear pair separations <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m1"><mml:mo>&lt;</mml:mo><mml:mn>10</mml:mn></mml:math> kpc are thus ideal candidates study along merger sequence since they coincide transformative period galaxies. However, dual AGNs can be extremely difficult confirm study. Hard X-ray ( id="m2"><mml:mo>&gt;</mml:mo><mml:mn>10</mml:mn></mml:math> keV) studies a relatively contamination-free tool probing dense obscuring environments predicted surround majority AGN mergers. To date, only handful brightest closest systems have been studied at these energies due demanding instrumental requirements involved. We demonstrate unique capabilities HEX-P spatially resolve soft - first time hard counterparts closely-separated id="m3"><mml:mrow><mml:mo stretchy="false">(</mml:mo><mml:mrow><mml:mo>∼</mml:mo><mml:msup><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mo>″</mml:mo></mml:mrow></mml:msup><mml:mo>−</mml:mo><mml:msup><mml:mrow><mml:mn>5</mml:mn></mml:mrow><mml:mrow><mml:mo>″</mml:mo></mml:mrow></mml:msup></mml:mrow><mml:mo stretchy="false">)</mml:mo></mml:mrow></mml:math> local Universe. By incorporating physically-motivated obscuration models, we reproduce realistic broadband spectra expected deeply embedded accreting SMBHs. resolved observations AGNs—accessible —will hence transform our understanding nearby