A broadband view on microquasar MAXI J1820+070 during the 2018 outburst

Abstract

The microquasar MAXI J\(1820+070\) went into outburst from mid-March until mid-July 2018 with several faint rebrightenings afterwards. With a peak flux of approximately 4 Crab in the \(20-50\) keV, energy range the source was monitored across the electromagnetic spectrum with detections from radio to hard X-ray frequencies. Using these multi-wavelength observations, we analyzed quasi-simultaneous observations from 12 April, near the peak of the outburst (\(\sim 23\) March). Spectral analysis of the hard X-rays found a \(kT_e \sim 30 \) keV and \( τ\sim 2\) with a \texttt{CompTT} model, indicative of an accreting black hole binary in the hard state. The flat/inverted radio spectrum and the accretion disk winds seen at optical wavelengths are also consistent with the hard state. Then we constructed a spectral energy distribution spanning \(\sim 12\) orders of magnitude using modelling in \texttt{JetSeT}. The model is composed of an irradiated disk with a Compton hump and a leptonic jet with an acceleration region and a synchrotron-dominated cooling region. \texttt{JetSeT} finds the spectrum is dominated by jet emission up to approximately \(10^{14}\) Hz after which disk and coronal emission dominate. The acceleration region has a magnetic field of \( B \sim 1.6 \times 10^4 \) G, a cross section of \(R \sim 2.8 \times 10^{9} \) cm, and a flat radio spectral shape naturally obtained from the synchroton cooling of the accelerated electrons. The jet luminosity of \(> 8 \times 10^{37} \) erg/s (\(> 0.15L_{Edd}\)) compared to an accretion luminosity of \( \sim 6 \times 10^{37}\) erg/s, assuming a distance of 3 kpc. Because these two values are comparable, it is possible the jet is powered predominately via accretion with only a small contribution needed from the Blanford-Znajek mechanism from the reportedly slowly spinning black hole.

References in corpus (9)

• The power of blazar jets
• Magnetic acceleration of relativistic AGN jets
• The corona contracts in a black-hole transient
• Reprocessing of X-rays in the outer accretion disc of the black hole binary XTE J1817--330
• An extremely powerful long-lived superluminal ejection from the black hole MAXI J1820+070
• Hard-state accretion disk winds from black holes: the revealing case of MAXI J1820+070
• A Model for Emission from Jets in X-ray Binaries: Consequences of a Single Acceleration Episode
• A timing study of MAXI J1820+070 based on Swift/XRT and NICER monitoring in 2018/19
• A model of the TeV flare of Cygnus X-1: electron acceleration and extended pair cascades

Cited by in corpus (10)

• agnpy: An open-source python package modelling the radiative processes of jetted active galactic nuclei
• Jet Parameters in the Black-Hole X-Ray Binary MAXI J1820+070
• Chasing the break: Tracing the full evolution of a black hole X-ray binary jet with multi-wavelength spectral modeling
• Accretion Scenario of MAXI J1820+070 during 2018 Outbursts with Multi-mission Observations
• Multiwavelength observations of MAXI J1820+070 during its outburst decay and subsequent mini-outburst
• A multi-wavelength study of the hard and soft states of MAXI J1820+070 during its 2018 outburst
• Gamma-ray observations of MAXI J1820+070 during the 2018 outburst
• NuSTAR and XMM-Newton observations of the binary 4FGL J1405.1-6119. A $\gamma$-ray emitting microquasar?
• A rapid optical and X-ray timing study of the neutron star X-ray binary Swift J1858.6-0814
• Evolution of Accretion Disk Structure of the Black Hole X-ray Binary MAXI J1820$+$070 during the Rebrightening Phase