Tidal disruption of stellar binaries as a pathway to exotic transients

Abstract Tidal disruption event (TDE) progenitors are commonly modelled as single stars on parabolic orbits around a supermassive black hole (SMBH), yet observations reveal a richer diversity of dynamical pathways. We show that tidal separation of stellar binaries by a 106 M⊙ SMBH provides a natural mechanism for producing eccentric TDEs. Using restricted three-body and SPH simulations, we model a solar-like star (SLS)–white dwarf (WD) binary on a parabolic orbit. The binary orbital phase governs the outcome: one component is captured onto a tightly bound orbit while the other is ejected as a hypervelocity object, naturally producing TDEs with eccentricities e ≠ 1. We classify these into Elliptical TDEs (eTDEs) and Hyperbolic TDEs (hTDEs), occurring with equal probability. For ∼88% of orientations the disruption is clean, with no mass accreted by the WD. The remaining ∼12%, in two narrow phase windows, leaves the WD with a captured debris envelope (WDDE). About a third of that, ∼4% of orientations, involves a direct WD–SLS collision near pericenter, with fallback peaking up to five times earlier and twenty times higher than for a single star; for the innermost ∼1.5% the total WDDE mass exceeds 1.4 M⊙, though the degenerate core does not, since the captured material forms a non-degenerate envelope, suggesting outcomes ranging from nova-like events to peculiar red giant-like objects. Depending on the phase, the mechanism may also produce repeating partial TDEs (rTDEs) and quasi-periodic eruptions (QPEs). Binary–SMBH encounters provide a robust channel for generating diverse TDEs with distinct observational signatures.