Publicly Offered Research
Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
サブミクロンの珪酸塩微粒子を数十m/sから数百m/sまで加速して衝突実験を行い，微粒子の合体が実際に起こるかどうかを実証することを目指す．これまでに衝突実験のための微粒子集合体加速方法の開発および速度計測系の構築を行った．今回の研究計画ではこれを継続，発展させ，衝突速度の関数としてサブミクロンサイズのガラス粒子と板状のガラスとの衝突における付着効率，付着強度を求めることを目的とする．
Impact experiments were conducted at a velocity of ~0.2-1.0 km/s using fine particles with several microns or sub-microns in size. For metal (Cu) plate targets, as previous impact experiments using projectiles with larger sizes than tens of micron, our experiments with the fine particles show that projectile materials can remain in the crater. For brittle (SiO2 glass) plate targets, though previous impact experiments using projectiles with larger sizes than tens of microns have shown the spallation and ejection of projectile materials, our experiments with the fine particles show that irreversible inelastic deformation of targets occurred like metals and that projectile materials can remain in the crater. This is explained by the absorption of impact energy determined via the competition between deformation and crack propagation. The deformation thus contributes to the energy absorption even for brittle materials at small sizes. Compiling our results and previous data, we found that sticking can occur in collisions with particles up to at least 1 cm for ductile (metal) targets and 10 microns for brittle targets at several hundred m/s. As an application, we evaluated the size distribution of dust grains in a debris disk where the sticking of fine particles is assumed to occur. We demonstrated that the collisional sticking modified the size distribution, resulting in the decrease of spectral energy distribution at millimeter wavelengths, consistent with the photometry data of this debris disk. This suggests that the sticking of fine particles occurs in this debris disk.
令和4年度が最終年度であるため、記入しない。
All 2024 2023 2021
All Journal Article (6 results) (of which Int'l Joint Research: 2 results, Peer Reviewed: 6 results, Open Access: 3 results) Presentation (3 results) (of which Int'l Joint Research: 2 results)
The Astrophysical Journal
Volume: 960 Issue: 1 Pages: 38-38
10.3847/1538-4357/acfee6
Planetary and Space Science
Volume: 236 Pages: 105763-105763
10.1016/j.pss.2023.105763
The Planetary Science Journal
Volume: 4 Issue: 5 Pages: 82-82
10.3847/psj/accbbb
Icarus
Volume: 366 Pages: 114530-114530
10.1016/j.icarus.2021.114530
Astronomy & Astrophysics
Volume: 647 Pages: A43-A43
10.1051/0004-6361/202039777
Volume: 195 Pages: 105141-105141
10.1016/j.pss.2020.105141
