2025MNRAS.537.3123Z

The first discovered interstellar small object, 'Oumuamua (1I/2017 U1), presents unique physical properties of extremely elongated geometric shape and dual characteristics of an asteroid and a comet. These properties suggest a possible origin through tidal fragmentation, which posits that 'Oumuamua was produced through intensive tidal fragmentation during a close encounter with a star or a white dwarf, resulting in its shape and ejection from its natal system. According to this mechanism, a high initial orbit eccentricity and a small pericentre of the parent body are necessary to produce 'Oumuamua-like objects. To verify whether this mechanism can occur in single giant planet systems, we conduct long-term numerical simulations of systems with a low-mass ($0.5\,M_\odot$) host star and a giant planet in this study. We determine that an eccentric orbit ($e_\text{p}\sim 0.2$) and a Jupiter-mass ($M_\text{p}\sim M_\text{J}$) of the planet appears to be optimal to generate sufficient perturbations for the production of 'Oumuamua-like objects. When the planetary semi-major axis $a_\text{p}$ increases, the proportion of planetesimals ejected beyond the system $P(\text{ej})$ increases accordingly, while the possibilities of ejected planetesimals undergoing stellar tidal fragmentation $P(\text{tidal}|\text{ej})$ remains relatively constant at $\sim 0.6~{{\ \rm per\ cent}}$. Focusing on stellar tidal fragmentation alone, the ratio of extremely elongated interstellar objects to all interstellar objects is $P_\text{e}\sim 3~{{\ \rm per\ cent}}$.