A Broadband View on Microquasar MAXI J1820+070 during the 2018 Outburst

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