A Search for X-ray/UV Correlation in the Reflection-Dominated Seyfert 1 Galaxy Mrk 1044

TL;DR

This study investigates the lack of UV/X-ray correlation in the Seyfert 1 galaxy Mrk 1044 despite strong X-ray reflection, suggesting complex interactions near the black hole and analyzing spectral features with XMM-Newton and NuSTAR.

Contribution

The paper provides the first detailed analysis of UV/X-ray correlation in Mrk 1044, combining spectral and timing data to explore the absence of expected reprocessing signals.

Findings

No significant UV/X-ray correlation detected.

Spectral analysis confirms strong relativistic reflection features.

High X-ray variability and relativistic effects may suppress correlation.

Abstract

Correlated variability between coronal X-rays and disc optical/UV photons provides a very useful diagnostic of the interplay between the different regions around an active galactic nucleus (AGN) and how they interact. AGN that reveal strong X-ray reflection in their spectra should normally exhibit optical/UV to X-ray correlation consistent with reprocessing -- where the optical/UV emission lag behind the X-rays. While such correlated delay has been seen in some sources, it has been absent in others. \rm{Mrk~1044} is one such source that has been known to reveal strong X-ray reflection in its spectra. In our analysis of three long \textit{XMM-Newton} and several \textit{Swift} observations of the source, we found no strong evidence for correlation between its UV and X-ray lightcurves both on short and long time scales. Among other plausible causes for the non-detection, we posit that higher X-ray variability than UV and strong general relativistic effects close to the black hole may also be responsible. We also present results from the spectral analysis based on \textit{XMM-Newton} and \textit{NuSTAR} observations, which show the strong soft X-ray excess and iron K$\alpha$ line in the 0.3--50 keV spectrum that can be described by relativistic reflection.