Дозвуковий рух частинки в рiдинi комплексної плазми в умовах мiкрогравiтацiї

• Date: 2018
• Main Authors: Zhukhovitskii, D. I., Fortov, V. E., Molotkov, V. I., Lipaev, A. M., Naumkin, V. N., Thomas, H. M., Ivlev, A. V., Morfill, G. E.
• Format: Article
• Language: English
• Published: Publishing house "Academperiodika" 2018
• Online Access: https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2018458
• Journal Title: Ukrainian Journal of Physics

Subsonic motion of a large particle moving through the bulk of a dust crystal formed by negatively charged small particles is investigated, by using the PK-3 Plus laboratory on the board of the International Space Station. Tracing the particle trajectories shows that the large particle moves almost freely through the bulk of a plasma crystal, while dust particles move along characteristic a-shaped pathways near the large particle. We develop a theory of the nonviscous motion of dust particles near a large particle and calculate particle trajectories. The deformation of a cavity around a large projectile moving with subsonic velocity in the cloud of small dust particles is investigated with a due regard for the friction between dust particles and atoms of a neutral gas. The pressure of a dust cloud at the surface of a cavity around the projectile can become negative, which entails the emergence of a considerable asymmetry of the cavity, i.e., the cavity deformation. The corresponding threshold velocity is calculated, which is found to decrease with increasing the cavity size. A good agreement with experiment validates our approach.