Searching for Correlations in Simultaneous X-ray and UV Emission in the Narrow-line Seyfert 1 galaxy 1H 0707-495

TL;DR

This study analyzes simultaneous X-ray and UV observations of galaxy 1H 0707-495, finding variable emissions with weak correlations and significant X-ray correlations at zero lag, suggesting a compact X-ray source near the black hole.

Contribution

It provides new insights into the correlation (or lack thereof) between X-ray and UV emissions in a specific Seyfert galaxy using multi-epoch observations.

Findings

X-ray variations are larger than UV variations.

Weak UV-X-ray correlation with UV leading X-ray.

Strong zero-lag correlation in X-ray bands.

Abstract

We examine simultaneous X-ray and UV light curves from multi-epoch 8 day XMM Newton observations of the narrow line Seyfert 1 galaxy 1H 0707-495. The simultaneous observations reveal that both X-ray and UV emission are variable and that the amplitude of the X-ray variations is significantly greater than that of the UV variations in both epochs. Using a discrete correlation function (DCF) the X-ray and UV light curves were examined for correlation on timescales up to 7.0 d. Low significance (~ 95 percent confidence) correlations with the UV leading the X-ray variations are observed. The lack of a significant correlation between the UV and X-ray bands seems consistent with the X-ray source being centrally compact and dominated by light bending close to the black hole. In addition, multi-band X-ray light curves were examined for correlations on similar timescales. Highly significant (> 99.9 per cent confidence) correlations were observed at zero lag consistent with previous studies of this AGN.