Energetic Electron and Proton Spectrometers MPS, SPS

The main objective of the charged particle and plasma experiments in the INTERBALL project is to study the spatial structure of the terrestrial magnetosphere as a global system in various scales and for varying external conditions. The subsatellites (Interball S2-T or S2-X for the Tail subsatellite and S2-A for the Auroral one) are equipped with ion/electron spectrometers similar to those aboard the two main Interball spacecraft.
The MPS spectrometer aboard S2-T is designed to carry out a long-period monitoring of the solar wind parameters and to register the ion fluxes in the bow-shock region when the satellite will be in the appropriate regions. MPS is oriented along the Sun-Earth direction. The SPS spectrometer is designed for estimating the ion energy and angular distributions and for measurements of the electron energy distributions.
The MPS (carried on both S2-A and S2-T) has two channels, and covers the ion energy range 0.2 to 20 keV in 16 steps (variable on command). Energy resolution is less than 10%. It utilizes a 127-degree electrostatic analyzer and channeltron. The angular aperture is 4 degrees both in the plane perpendicular to the main axis and in the plane parallel to it.
The SPS has three channels for ions, one for electrons, and covers the energy range 0.2 to 20 keV in 16 steps (variable on command). Energy resolution is less than 10%. SPS utilizes a double hemispherical analyzer with microchannel plates. The angular aperture in the plane parallel to the main axis is 3 x 45 degrees for ions and 135 degrees for electrons. In the plane perpendicular to the main axis, the aperture is 4 degrees.
The MPS and SPS spectrometers have limited angular characteristics; for this reason the S2-T spacecraft includes the VDP-S instrument (95-039F-08), which is designed for rapid determination of the ion flux direction variations.

INTERBALL项目中带电粒子与等离子体实验的主要目标是研究地球磁层作为全球系统在不同尺度及不同外部条件下的空间结构。子卫星（Interball S2-T 或 S2-X 为尾部子卫星，S2-A 为极光子卫星）配备了与两艘主Interball航天器上相似的离子/电子能谱仪。S2-T上的MPS谱仪旨在进行长期监测太阳风参数，并在卫星进入适当区域时记录弓形激波区域的离子通量。MPS沿太阳-地球方向对准。SPS谱仪设计用于估算离子的能量和角分布，以及测量电子的能量分布。MPS（携带于S2-A和S2-T）具有两个通道，覆盖从0.2 keV至20 keV的离子能量范围，分为16个步骤（可根据指令调整）。能量分辨率低于10%。它采用一个127度的静电分析仪和通道电子倍增器。在垂直于主轴和平行于主轴的平面上的角孔径均为4度。SPS具有三个离子通道，一个电子通道，覆盖从0.2 keV至20 keV的能量范围，分为16个步骤（可根据指令调整）。能量分辨率低于10%。SPS采用双半球分析仪和微通道板。在平行于主轴的平面上的角孔径为离子3 x 45度，电子135度。在垂直于主轴的平面上的孔径为4度。由于MPS和SPS谱仪的角特性有限，因此S2-T航天器包括了VDP-S仪器（95-039F-08），该仪器旨在快速确定离子通量方向的变化。