Outer Solar System Perihelion Gap Formation through Interactions with a Hypothetical Distant Giant Planet

Among the outer solar system minor planet orbits there is an observed gap in perihelion between roughly 50 and 65 au at eccentricities $e\gtrsim0.65$. Through a suite of observational simulations, we show that arises from two separate populations, Extreme Trans-Neptunian Objects (ETNOs; perihelia $q\gtrsim40$ semimajor axes $a\gtrsim150$ au) Inner Oort Cloud objects (IOCs; $q\gtrsim65$ $a\gtrsim250$ au), very unlikely to result realistic single, continuous distribution objects. We also explore connection hypothetical distant giant planet, often referred as Planet 9 or X, using dynamical simulations. Some simulations containing X produce ETNOs, IOCs, simple Kuiper-Belt-like initial particle over age system. The forms particles scattered high eccentricity by Neptune are captured into secular resonances with where they cross oscillate hundreds kiloyears. Many these reach minimum their oscillation cycle within IOC region increasing mean residence time factor approximately five region. Our findings imply that, presence massive external perturber, will be discovered, but only $\sim20$% numerous nearby population ($65$ $\lesssim q \lesssim 100$ au).