Alternative possibility of GW190521: Gravitational waves from high-mass black hole-disk systems

We evolve high-mass disks of mass $15$-$50M_\odot$ orbiting a $50M_\odot$ spinning black hole in the framework numerical relativity. Such systems could be an outcome during collapse rapidly-rotating very-massive stars. The massive are dynamically unstable to so-called one-armed spiral-shape deformation with maximum fractional density-perturbation $\delta \rho/\rho \gtrsim 0.1$, and hence, high-amplitude gravitational waves emitted. waveforms characterized by initial burst frequency $\sim 40$-$50$ Hz amplitude $(1$-$10)\times 10^{-22}$ at hypothetical distance 100 Mpc subsequent low-amplitude quasi-periodic oscillation. illustrate that our models wide range disk resemble GW190521. also point out from stars can source for 3rd-generation gravitational-wave detectors exploring formation process rapidly-spinning holes 50$-$100M_\odot$ early universe.