A unified accretion ejection paradigm for X-ray binaries : the JED-SAD paradigm
Abstract
The hysteresis behavior of X-ray binaries during their outbursts remains a mystery. In this work, we developed a paradigm where the disk material accretes in two possible, mutually exclusive, ways (Ferreira et al. 2006). In the usual alpha-disk mode (SAD, Shakura & Sunayev 73), the dominant local torque is due to a radial transport of the disk angular momentum. In the jet-emitting disk mode (JED), magnetically-driven jets carry away mass, energy, and all the angular momentum vertically. Within this framework, the transition from one mode to another is related to the magnetic field distribution, an unknown. We developed a two-temperature plasma code that computes the thermal balance at each radius for a large ensemble of disk parameters (Marcel+18a, A&A 615, A57). These parameter include the disk accretion rate (mdot) and a transition radius between the two accretion modes (rJ). The local spectra of any set of parameter is self-consistently computed at each radius, providing the global spectra emitted by the entire disk. We have shown that typical hard states of X-ray binaries can be reproduced up to unprecedented X-ray luminosities in this paradigm. In addition, we used a simple physical model to estimate the radio fluxes (at 8.6-9 GHz) radiated by the jets for any given set of parameter. Strikingly, both spectral features fit extremely well. Playing now on both mdot and rJ, we have shown that the X-ray spectral behavior of the X-ray binary GX 339-4 can be covered, both in X-ray and radio (Marcel+18b, A&A 617, A46). We then used a fitting procedure, including both RXTE observations (3-200 keV) and ATCA fluxes (9 GHz), that reproduced all X-ray spectral shapes and radio fluxes from GX339-4 between 1996 to 2011 (Marcel et al., 2019, A&A 626, A115). This is, to our knowledge, the first time that accretion-ejection cycles are being reproduced, using both accretion (X-rays) and ejection (radio) constraints. Direct spectral fits have since been performed on XMM-Newton+NuSTAR data from the AGN HE 1143-1810 (Ursini et al,. 2020, A&A 634, A92), XRT+NICER+NuSTAR+BAT data from the X-ray binary MAXI J1820+070 (Marino et al. 2021, A&A 656, A63), and RXTE data from the X-ray binary GX 339-4 (Barnier et al. 2022, A&A 657, A11). Moreover, we have addressed the production of low frequency quasi-periodic oscillations during the outbursts (Marcel et al. 2020, A&A 640, A18), as well as the radiative efficiency of the accretion flow and the associated radio--X-ray correlation (Marcel et al. 2021, A&A in press). I will introduce the model and present a summary of all its associated results.
- Publication:
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44th COSPAR Scientific Assembly. Held 16-24 July
- Pub Date:
- July 2022
- Bibcode:
- 2022cosp...44.1772M