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الملخص الأصلي

كما كتبه المؤلفون، بالإنجليزية arXiv:2604.22961

Planetary systems can act as sensitive gravitational detectors for dark matter. We investigate the gravitational scattering of Oort cloud objects by primordial black holes (PBHs) as a potential component of the Galactic dark matter halo. Calculating the rates at which PBH encounters eject objects from the Oort cloud or inject them into Earth crossing orbits, we find a linear scaling $$\Gamma \propto m_{\mathrm{PBH}}$$ for $$m_{\mathrm{PBH}} \gtrsim 10^{-10} M_\odot$$. For $$m_{\mathrm{PBH}} \sim 10^3 M_\odot$$, PBHs constituting all local dark matter would eject $$\sim1.3\times10^{12}$$ objects over the Solar System's lifetime, comparable to the total Oort cloud population and inject $$\sim2.6\times10^{10}$$ objects into Earth-crossing orbits. Comparing these rates with observational constraints from long period comet fluxes and terrestrial impact records, we derive upper limits on the PBH dark matter fraction $$f_{\mathrm{PBH}}$$. Our most stringent constraints exclude $$f_{\mathrm{PBH}}=1$$ for $$10^2 M_\odot \lesssim m_{\mathrm{PBH}} \lesssim 10^5 M_\odot$$, with $$f_{\mathrm{PBH}} \lesssim 0.002$$ at $$m_{\mathrm{PBH}} = 10^3 M_\odot$$. For the asteroid mass window ($$10^{17}$$-$$10^{23}$$ g), scattering rates are far too low to produce observable effects. These Solar System-based constraints complement existing astrophysical probes and demonstrate that planetary systems can serve as sensitive gravitational detectors for compact dark matter.