State transitions in black hole Xray binaries are likely caused by gas evaporation from a thin accretion disk into a hot corona. We present a heightintegrated version of this process, which is suitable for analytical and numerical studies. With radius
Spinning supermassive black holes (BHs) in active galactic nuclei magnetically launch relativistic collimated outflows, or jets. Without angular momentum supply, such jets are thought to perish within 3 orders of magnitude in distance from the BH, well before reaching kiloparsec scales. We study the survival of such jets at the largest scale separation to date, via 3D general relativistic magnetohydrodynamic simulations of rapidly spinning BHs immersed into uniform zeroangularmomentum gas threaded by a weak vertical magnetic field. We place the gas outside the BH sphere of influence, or the Bondi radius, chosen to be much larger than the BH gravitational radius,
 NSFPAR ID:
 10497691
 Publisher / Repository:
 DOI PREFIX: 10.3847
 Date Published:
 Journal Name:
 The Astrophysical Journal
 Volume:
 964
 Issue:
 1
 ISSN:
 0004637X
 Format(s):
 Medium: X Size: Article No. 79
 Size(s):
 Article No. 79
 Sponsoring Org:
 National Science Foundation
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Abstract r scaled to Schwarzschild units and coronal mass accretion rate to Eddington units, the results of the model are independent of black hole mass. State transitions should thus be similar in Xray binaries and an active galactic nucleus. The corona solution consists of two powerlaw segments separated at a break radius ${\stackrel{\u0307}{m}}_{c}$r _{b}∼ 10^{3}(α /0.3)^{−2}, whereα is the viscosity parameter. Gas evaporates from the disk to the corona forr >r _{b}, and condenses back forr <r _{b}. Atr _{b}, reaches its maximum, ${\stackrel{\u0307}{m}}_{c}$ . If at ${\stackrel{\u0307}{m}}_{c,\mathrm{max}}\approx 0.02\phantom{\rule{0.25em}{0ex}}{(\alpha /0.3)}^{3}$r ≫r _{b}the thin disk accretes with , then the disk evaporates fully before reaching ${\stackrel{\u0307}{m}}_{d}<{\stackrel{\u0307}{m}}_{c,\mathrm{max}}$r _{b}, giving the hard state. Otherwise, the disk survives at all radii, giving the thermal state. While the basic model considers only bremsstrahlung cooling and viscous heating, we also discuss a more realistic model that includes Compton cooling and direct coronal heating by energy transport from the disk. Solutions are again independent of black hole mass, andr _{b}remains unchanged. This model predicts strong coronal winds forr >r _{b}, and aT ∼ 5 × 10^{8}K Comptoncooled corona forr <r _{b}. Twotemperature effects are ignored, but may be important at small radii. 
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