Numerical simulation of the ion focusing process in a dust impact time of flight mass spectrometer

Приведено описание конструкции пылеударного времяпролетного масс-спектрометра. Рассмотрен способ расчета траектории заряженной частицы на треугольной сетке. Дано описание реализаций алгоритма расчета для персонального компьютера, GPU ускорителя и суперкомпьютера. Приведены основные различия реализаций, сравнение производительности и точности расчета. Рассмотрены преимущества и недостатки каждой из реализаций. A description of a design of dust-impact time of flight mass-spectrometer is given. A method for calculating the trajectory of a charged particle on a triangular grid is considered. The implementation of the calculation algorithm for the personal computer, the GPU accelerator and the supercomputer is described. The main differences in implementations, comparison of performance and accuracy of calculation are given. The advantages and disadvantages of each of the implementations are considered

Determining the spacecraft Foton M-4 attitude motion

Abstract: The paper presents the results of reconstruction of the spacecraft Foton M-4 attitude motion in the single-axis solar orientation mode. The reconstruction is based on processing the measurements of two vectors: the spacecraft angular rate and the strength of the Earth magnetic field. The processing technique uses kinematical equations of the attitude motion of a rigid body. In its framework, the measurement data of both types, collected on a time interval, are processed jointly. The angular rate data are interpolated by piecewise linear functions and those functions are substituted in kinematical equations for components of the quaternion, which defines a transformation of the spacecraft coupled coordinate system to the inertial one. The equations obtained present the kinematical model of a spacecraft attitude motion. The solution of the equations, which approximates the real motion, is found by the least squares method from the condition of the best agreement between measurement and calculation data of the magnetic strength. The technique allows to reconstruct the attitude motion on time intervals more than 10 hours. The found reconstructions are used for calculation of residual accelerations onboard the spacecraft.Note: Research direction:Theoretical and applied problems of mechanic