English

Testing X-ray Reprocessing and Mapping the Soft Excess of NGC 7469 with NICER

High Energy Astrophysical Phenomena 2025-06-12 v1 Astrophysics of Galaxies

Abstract

We present an X-ray/UV reverberation analysis of NGC 7469 across 210 days, using daily NICER observations with contemporaneous monitoring by Swift UVOT+XRT. We model the X-ray spectrum with a power law continuum and a soft excess during each NICER epoch. These emission sources demonstrate correlated flux variability with a lag consistent with zero days. We find that the power law emission is consistent with a compact X-ray corona, and that the soft excess can be explainedby reflected coronal emission from the inner accretion disk. We test the relationship between changes in the flux of the X-ray corona and the UVW2 continuum, finding strong correlation and a negative X-ray lag of less than one day. This is consistent with a scenario in which the X-ray corona drives the UVW2 light curve through thermal reprocessing

Keywords

Cite

@article{arxiv.2504.20223,
  title  = {Testing X-ray Reprocessing and Mapping the Soft Excess of NGC 7469 with NICER},
  author = {Ethan R. Partington and Edward M. Cackett and Rick Edelson and Keith Horne and Jake A. Miller and Aaron J. Barth and Jonathan Gelbord and Juan V. Hernández Santisteban},
  journal= {arXiv preprint arXiv:2504.20223},
  year   = {2025}
}

Comments

18 pages, 8 figures, Accepted to ApJ