Relaxation of spherical stellar systems
Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) 490:1 (2019) 478-490
Stabilisation of short-wavelength instabilities by parallel-to-the-field shear in long-wavelength $\mathbf{E} \times \mathbf{B}$ flows
(2019)
Hierarchical Black Hole Mergers in Active Galactic Nuclei.
Physical review letters American Physical Society (APS) 123:18 (2019) ARTN 181101
Abstract:
The origins of the stellar-mass black hole mergers discovered by LIGO/Virgo are still unknown. Here we show that if migration traps develop in the accretion disks of active galactic nuclei (AGNs) and promote the mergers of their captive black holes, the majority of black holes within disks will undergo hierarchical mergers-with one of the black holes being the remnant of a previous merger. 40% of AGN-assisted mergers detected by LIGO/Virgo will include a black hole with mass ≳50M_{⊙}, the mass limit from stellar core collapse. Hierarchical mergers at traps in AGNs will exhibit black hole spins (anti)aligned with the binary's orbital axis, a distinct property from other hierarchical channels. Our results suggest, although not definitively (with odds ratio of ∼1), that LIGO's heaviest merger so far, GW170729, could have originated from this channel.Validation of gyrokinetic simulations of a National Spherical Torus eXperiment H-mode plasma and comparisons with a high-k scattering synthetic diagnostic
Plasma Physics and Controlled Fusion IOP Publishing 61:11 (2019) 115015-115015
The Probability Distribution of Astrophysical Gravitational-Wave Background Fluctuations
ArXiv 1910.04587 (2019)