The Complete XMM-SERVS Survey: A Sensitive X-ray Survey of the LSST Deep-Drilling Fields*

Cosmic X-ray surveys over the past two decades have played a critical role in transforming our understanding of growing supermassive black holes (SMBHs) in the distant universe. I will describe one key survey, now recently completed, advancing this effort: the 13.1 deg² XMM-SERVS survey. XMM-SERVS has successfully mapped three legacy sky fields at 50 ks depth: the SERVS areas of CDF-S, XMM-LSS, and ELAIS-S1. These fields have first-rate multiwavelength coverage already and are LSST/DES Deep-Drilling Fields, MOONS/PFS massive spectroscopy fields, prime TolTEC/ALMA fields, and multi-object reverberation-mapping fields. Multiwavelength fitting of infrared-to-X-ray spectral energy distributions is now being used to characterize the active galactic nuclei (AGNs) and galaxies in these fields, enabling further in-depth investigations. When the follow-up of its 12,000 X-ray sources is complete, XMM-SERVS should dramatically advance studies of links between SMBH accretion and host-galaxy properties, SMBH growth across the full range of cosmic environments, groups/clusters at z = 0.1-2, protoclusters, and other topics.