Uncapped simulation of delayed post-perihelion splittings

Determine whether the mantle-resealing mechanism in the interstellar-comet fragmentation model produces delayed post-perihelion splittings analogous to those observed for 2I/Borisov by conducting simulations with a tracking limit higher than 64 fragments.

Background

The primary simulation reaches the imposed 64-body tracking cap near perihelion, which prevents the model from resolving subsequent fragmentation events. Consequently, the reported absence of outbound splitting events is a numerical consequence of the cap rather than evidence that the physical mechanism cannot produce them.

The model includes mantle formation and resealing: as activity declines, dust lifting weakens, mantles reform, and confined subsurface gas pressure may build again. The authors identify this as a possible explanation for delayed fragmentation observed in 2I/Borisov, but its behavior cannot be assessed in the capped simulation. An uncapped or higher-limit calculation is therefore required to determine whether the proposed mechanism produces delayed post-perihelion splitting.

References

The tracking cap is reached at perihelion, so the outbound leg is necessarily split-free in this run (0 post-perihelion events); whether the model's mantle-resealing channel would produce delayed, post-perihelion splittings---as observed for 2I/Borisov \citep{jewitt20}---is censored by the cap and left to future runs with a higher tracking limit.

— Fragmentation Dynamics of Pristine Interstellar Comets: An Exploratory Multi-Physics Simulation Study  (2609.20773 - Karamiqucham, 17 Sep 2026) in Section 3, subsection “Primary case: emergent disaggregation at q=1 AU”