Investigating the disc-jet coupling in accreting compact objects using the black hole candidate Swift J1753.5-0127

TL;DR

This study examines the coupling between accretion and jet ejection in the black hole candidate Swift J1753.5-0127 through a four-year multiwavelength observational campaign, revealing a weaker jet than predicted and thermal disc dominance in near-infrared emission.

Contribution

It provides detailed observational evidence of a faint jet in Swift J1753.5-0127, challenging existing empirical correlations and offering insights into jet properties and accretion processes in such systems.

Findings

Jet is fainter than expected from empirical radio-X-ray correlations.

Near-infrared emission is dominated by thermal disc emission, unusual for this state.

Results have implications for broadband jet modeling and understanding of compact object nature.

Abstract

In studies of accreting black holes in binary systems, empirical relations have been proposed to quantify the coupling between accretion processes and ejection mechanisms. These processes are probed respectively by means of X-ray and radio/optical-infrared observations. The relations predict, given certain accretion conditions, the expected energy output in the form of a jet. We investigated this coupling by studying the black hole candidate Swift J1753.5-0127, via multiwavelength coordinated observations over a period of ~4 years. We present the results of our campaign showing that, all along the outburst, the source features a jet that is fainter than expected from the empirical correlation between the radio and the X-ray luminosities in hard spectral state. Because the jet is so weak in this system the near-infrared emission is, unusually for this state and luminosity, dominated by thermal emission from the accretion disc. We briefly discuss the importance and the implications of a precise determination of both the slope and the normalisation of the correlations, listing some possible parameters that broadband jet models should take into account to explain the population of sources characterized by a dim jet. We also investigate whether our data can give any hint about the nature of the compact object in the system, since its mass has not been dynamically measured.