2025/11/03 by Diaz, Carlos Garcia, Wang, Q. Daniel, Harrington, Kevin C. +12
Physics and Astronomy · #Galaxies: Formation, Evolution, Phenomena #Astrophysical Phenomena and Observations #Astronomy and Astrophysical Research
paper · doi:10.48550/arxiv.2511.02037
We present an analysis of XMM-Newton X-ray observations of PJ1053+60, a hyperluminous infrared galaxy (HyLIRG) at z=3.549 that is strongly lensed by a foreground group at z=0.837. We also present GNIRS spectroscopy confirming the presence of an active galactic nucleus (AGN) to the southwest of PJ1053+60 (AGNSW) at zSW = 1.373 ± 0.006. Using this redshift prior, we decompose the X-ray spectrum of PJ1053+60 into AGNSW and high-mass X-ray binary (HMXB) components from the HyLIRG. The HMXB component has an unusually high luminosity, ∼ 50 times higher than calibration derived from local galaxies, and a characteristic photon index likely too flat to be caused by high-mass X-ray binaries at rest frame energies above a few keV. Our 2-D spatial decomposition also suggests a similarly high X-ray HMXB luminosity, although the limited spatial resolution prevents meaningful morphological constraints on the component. We conclude that the enhanced X-ray emission may only be explained by the presence of another AGN (AGNFG) embedded in the foreground group lensing the PJ1053+60 system. The presence of AGNFG is further supported by the detection of a point-like radio continuum source that coincides with the brightest group galaxy (BGG) of the foreground lens. Our study demonstrates the limited capability of current X-ray observatories while highlighting the need for higher angular resolution observations to definitively characterize the nature of X-ray emission in distant, strongly lensed HyLIRGs.