7 research outputs found
The Kinetic and Hydrodynamic Bohm Criterions for Plasma Sheath Formation
The purpose of this paper is to mathematically investigate the formation of a
plasma sheath, and to analyze the Bohm criterions which are required for the
formation. Bohm derived originally the (hydrodynamic) Bohm criterion from the
Euler--Poisson system. Boyd and Thompson proposed the (kinetic) Bohm criterion
from kinetic point of view, and then Riemann derived it from the
Vlasov--Poisson system. In this paper, we prove the solvability of boundary
value problems of the Vlasov--Poisson system. On the process, we see that the
kinetic Bohm criterion is a necessary condition for the solvability. The
argument gives a simpler derivation of the criterion. Furthermore, the
hydrodynamic criterion can be derived from the kinetic criterion. It is of
great interest to find the relation between the solutions of the
Vlasov--Poisson and Euler--Poisson systems. To clarify the relation, we also
study the hydrodynamic limit of solutions of the Vlasov--Poisson system.Comment: 24 pages, 2 figure
イオン音波の非線形現象 : ソリトンからカオスへの遷移およびシース構造の分岐
学位の種別: 課程博士審査委員会委員 : (主査)東京大学教授 吉田 善章, 東京大学教授 小川 雄一, 東京大学教授 鈴木 宏二郎, 東京大学准教授 西浦 正樹, 日本大学元教授 戸次 直明University of Tokyo(東京大学