Evidence that the Bursting Component of the X-ray Radiation From 3C 111 Originates in the PC-Scale Jet

TL;DR

This study provides observational evidence that the long-duration X-ray bursts in 3C 111 originate from blobs ejected in the pc-scale jet, not from the accretion disc, based on correlated timing of X-ray and radio emissions.

Contribution

It is the first to directly link long-timescale X-ray bursts in 3C 111 to jet ejections rather than accretion disc activity.

Findings

X-ray and radio bursts are highly correlated with X-ray leading by ~100 days.

X-ray bursts last 1-3 years and are associated with ejected blobs in the jet.

The origin of long-term X-ray variability is pinpointed to the pc-scale jet.

Abstract

Evidence is presented indicating that the bursting component of the X-ray radiation detected in the nuclear region of the active radio galaxy 3C 111 comes from the blobs ejected in the pc-scale jet and not from the accretion disc. After each new outburst the radio flux density associated with it increases to a peak in ~1 year and then subsides over a period of 1-2 years with the flux falling off exponentially as the blob moves outward and dissipates. Similar peaks (bursts) are seen in the X-ray light curve and a cross-correlation between the two shows a very high correlation with the X-ray peaks leading the radio peaks by ~100 days. A second cross-correlation, this time between the radio event start times and the X-ray light curve, also shows a significant correlation. When this is taken together with the long (~1 yr) delay between the start of each ejection event and its associated X-ray peak it indicates that this bursting component of the X-ray flux must be associated with the ejected blobs in the pc-scale jet and not with the accretion disc. Because X-ray telescopes do not have the resolution required to resolve the accretion disc area from the pc-scale jet, this paper is the first to present observational evidence that can pinpoint the point of origin of at least those long-timescale X-ray bursts with durations of 1-3 yrs.