Dust production by impacts of interstellar dust on Edgeworth-Kuiper Belt objects

We estimated the production rate of dust grains by the impacts of interstellar dust grains on Edgeworth-Kuiper Belt objects (EKOs). In this scenario, the impact ejecta become interplanetary dust particles with radii smaller than about 10 μm. If the EKOs have hard icy surfaces and there are ∼ 1013 of these with radii≥0.1 km, the total dust production rate over the entire Edgeworth-Kuiper Belt ranges from 3.7 × 105g s−1 to 2.4 × 106g s−1, depending on the adopted minimum ejection velocity (10 cm s−1 ∼103 cm s−1). If the surfaces of EKOs are covered by a layer of icy particles with radii smaller than those of the incident dust grains, then the total dust production rate is enhanced slightly to about 3.1× 107g s−1. Adopting the different collisional parameters used by Stern (1996), we find that the production rate of dust grains with radii smaller than 10μm by mutual collisions of EKOs is between 8.6 × 104g s−1 and 2.9 × 107g s−1. Therefore dust production due to the impacts by interstellar dust on EKOs is a significant source of interplanetary dust grains, at least for those far from the sun with radii smaller than about 10 μm.