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Description
We investigate the tidal stripping of a cold helium white dwarf (WD) by a stellar-mass black hole (BH). Owing to the degenerate nature of the WD, quantum effects are expected to play a significant role in the dynamics. To capture these effects, we employ a full quantum hydrodynamic framework to simulate the formation of the accretion disk. The WD is modelled as a Bose–Fermi droplet composed of attractively interacting degenerate atomic bosons and fermions. The droplet is placed in the field of a non-rotating BH. We use the pseudo-Newtonian potential by Paczynski and Wiita.
Our numerical simulations show that the infalling material undergoes fragmentation during disc formation as a result of nonlinear effects. The quantum matter captured by the BH after periastron passage acts as a source of intense electromagnetic emission, producing bursts that resemble the recurrent flaring observed in X-ray sources. We also identify quantised vortices in the bosonic component of the accretion disc that may produce distinct electromagnetic signatures. Their formation naturally explains the occurrence of flicker noise. After tidal stripping, the remnant WD recedes from the BH while quantum vortices propagate along its surface. We also investigate the gravitational radiation generated during this process.