Correlations of Disk and Jet Emission Deviating from the Fundamental Plane

TL;DR

This study investigates how variability in accretion disk emission influences the correlation with jet emission, revealing deviations from the fundamental plane of black hole activity due to variability suppression effects.

Contribution

It demonstrates that disk-jet correlations can deviate from the fundamental plane when disk variability is considered, highlighting the importance of timescale in luminosity measurements.

Findings

Correlations are shallower than the fundamental plane.

Correlation slope increases with observed frequency.

Deviations relate to variability suppression in jets.

Abstract

The variability of accretion rate, which is believed to induce the aperiodic variability of X-ray emission from disk, may affect the energy injection into the jet. In this spirit, a correlation between disk emission and jet emission can be formed even if the mean luminosity of disk emission keeps constant. In this work, these correlations are found in the situation that the luminosity of disk emission is variable and kept with a constant mean value. The obtained correlations may be shallower than that of the fundamental plane of black hole activity. In addition, the slope of correlation may increase with increasing observed frequency of jet emission. For the luminosities spacing with three days, the slope of correlation decreases with increasing black hole mass. The deviation of our found correlations from that of the fundamental plane is related to the suppression of variability in the jet emission in comparison with that in the disk emission. This mechanism may work in some sources in which shallower correlations have been reported. Moreover, it implies that luminosities used to estimate the relation of fundamental plane should cover an appropriate timescale, in which the variability of jet emission is not significantly suppressed.