Current status and future plans for the general antiparticle spectrometer (GAPS)

We discuss current progress and future plans for the general antiparticle spectrometer experiment (GAPS). GAPS detects antideuterons through the X-rays and pions emitted during the deexcitation of exotic atoms formed when the antideuterons are slowed down and stopped in targets. GAPS provides an exceptionally sensitive means to detect cosmic-ray antideuterons. Cosmic-ray antideuterons can provide indirect evidence for the existence of dark matter in such form as neutralinos or Kaluza–Klein particles. We describe results of accelerator testing of GAPS prototypes, tentative design concepts for a flight GAPS detector, and near-term plans for flying a GAPS prototype on a balloon.     

The RadioAstron project: Measurements and analysis of basic parameters of space telescope in flight in 2011–2013

The results of a large number of the antenna radiometric measurements at bands of 92, 18, 6.2, 1.35, and 1.7-1.2 cm are presented by the data of the standard telemetry system of the Spektr-R spacecraft. Both special sessions of calibration object observations in the mode of a single space radio telescope (SRT) operation and numerous observations of researched sources in the mode of the ground-space interferometer were used. The obtained results agree with the first results of Kardashev et al. (2013), i.e., within 10–15% at bands of 92, 18, and 6.2 cm and 20–25% at the band of 1.35 cm. In the main, the measurements for the eight subbands at wavelengths of 1.7-1.2 cm indicate a monotonic increase in the spectral system equivalent flux density (SEFD) of noise radiation with a frequency consistent with the calculated estimates for the discussed model. The sensitivity of the ground-space interferometer for the five subbands at wavelengths from 1.35 to 1.7 cm can be higher by a factor of 1.5, and for the three subbands from 1.35 to 1.2 cm lower by a factor of 1.5 than at the band of 1.35 cm. The SRT contribution to the interferometer sensitivity proportional to the square root of SEFD is close to the design one at the bands of 92 and 18 cm and decreases the design sensitivity approximately by a factor of 1.5 and 2 at the bands of 6.2 and 1.35 cm, respectively. These differences of implemented values from the design ones were not significantly affected the scientific program implementation.     

Plasma convection model and generation of longitudinal currents in the earth's magnetosphere

The aim of this paper is to investigate processes in the magnetosphere and in particular the problems of the interaction of the solar wind with the Earth's magnetic field to produce large-scale convection, electric fields and longitudinal currents in the magnetosphere. The investigation is carried out in the frame of magnetic hydrodynamics. The reason for such an approach can be found in /1/. When calculating the transfer coefficients, the Böhm approximation is used, i.e. it is considered that the plasma in the near-equatorial part of the magnetosphere (quasiplanar geometry is used in the problem for simplification) is sufficiently turbulent that the condition ωτ ≈ 1 is valid (ω is the Larmor frequency of electrons, τ is effective time between two Quasi-collisions). The main subjects of investigation in this paper are the input near the equatorial boundary layer and the plasma layer of the magnetosphere tail.     

导弹动力系统最佳预防维修周期的数字仿真

导弹武器系统中有很多是多次使用的可修复杂系统。对于这种复杂系统，尤其是其寿命周期，预防维修时间及事后维修时间为离散分布时，其最佳预防维修周期难以用一般方法求得。针对这种情况，本文利用蒙特卡罗随机模拟法建立了系统计算模型，并通过模拟计算，得出了最佳预防维修周期的数字仿真结果。此结果可为制定导弹武器最佳修复策略提供依据。     

An empirical model of electron density for low and middle latitudes below 200 km

Our empirical model of electron density (n_e) for quiet and weakly disturbed geomagnetic conditions (Kp not greater 4) takes account of comparative analysis of existing models and of experimental data obtained by rockets and incoherent scatter radar. The model describes the n_e distribution in the 80 to 200 km height range at low and middle latitudes, and to some extent, in the subauroral region. It is presented in analytical form thus allowing one to calculate electron density profiles for any time. The electron density distribution at 140 km depends on the season (day of the year) and on the solar zenith angle. Profile variations during the day are for one season shown. Different from other models, ours specifies the variations during sunrise and sunset and reflects the particular profile shape at night admitting the occurrence of an intermediate layer.     

着陆姿态对地外天体表层采样的影响研究

表层采样技术是获得地外天体特性的重要手段,是完成地外天体采样任务的一项关键技术。文章结合4自由度表层采样装置的特点,建立了表层采样装置的逆运动学模型,分析了极限着陆姿态下表层采样装置安装位置在当地参考坐标系中的变化,并针对一次封装与二次封装过程中表层采样装置的位置和姿态要求,明确了末端采样器姿态补偿方法,提出了着陆姿态对表层采样影响的分析算法。仿真结果表明,该算法能有效分析着陆姿态对表层采样的影响,可为表层采样装置适应性设计提供支持。     

Electrodynamic stabilization of earth-orbiting satellites in equatorial orbits

A satellite with electrodynamic stabilization system is considered. Based on the method of Lyapunov functions, sufficient conditions of the asymptotic stability of direct equilibrium position of this satellite in the orbital coordinate system under perturbing action of a gravitational moment are obtained. These conditions allow one to ensure a rational choice of parametric control coefficients depending on parameters of the satellite and its orbit.     

Study of backward propagating Langmuir waves with PIC simulation

The conversion of Langmuir waves into electromagnetic radiations is an important mechanism of solar type III bursts. Langmuir waves can be easily excited by electron beam instability, and they can be converted into backward propagating Langmuir waves by wave–wave interaction. Generally, the backward propagating Langmuir waves are very important for the second harmonic emission of solar type III bursts. In this work, we pay particular attention to the mechanism of the backward propagating Langmuir waves by particle in cell (PIC) simulations. It is confirmed that the ions play a key role in exiting the backward propagating Langmuir waves. Moreover, the electron beam can hardly generated the backward propagating Langmuir waves directly, but may directly amplify the second harmonic Langmuir waves.     

Improved Accuracy Metallic Resonator CVG

Metallic resonator Q-factor is very sensitive to the resonator's material, its thermal and chemical treatment, design, and environment; i.e., pressure and temperature. In order to obtain higher accuracy for CVG it is necessary to use resonator evacuation. Resonator mass plays a very important role in sensitivity to angle rate, in stability of vibration, in response to environmental condition changes, and also to external vibration and shock resistance. tnnalabs Holding Inc. uses a cylindrical resonator with increased rim thickness of up to 2 mmn and more. This concerns resonator material and design parameters selection, material thermal treatment to increase resonator Q-factor, and improved control algorithms in order to increase metallic CVG accuracy. As a result, CVG bias instability of 0.025 degth and random walk of 0.008 degvh for the resonator diameter 43 mmn, and 0.2 deg/h for the resonator diameter 25 mm were obtained. Future opportunities for Innalabs CVG is also discussed herein. Test results are presented for CVG43 and CVG25. Three-axis CVG unit under control of one DSP "Sharc" and IMU parameters are forecasted.     

Relativistic electrons high doses at International Space Station and Foton M2/M3 satellites

The paper presents observation of relativistic electrons. Data are collected by the Radiation Risk Radiometer-Dosimeters (R3D) B2/B3 modifications during the flights of Foton M2/M3 satellites in 2005 and 2007 as well as by the R3DE instrument at the European Technology Exposure Facility (EuTEF) on the Columbus External Payload Adaptor at the International Space Station (ISS) in the period February 20 – April 28, 2008. On the Foton M2/M3 satellites relativistic electrons are observed more frequently than on the ISS because of higher (62.8°) inclination of the orbit. At both Foton satellites the usual duration of the observations are a few minutes long. On the ISS the duration usually is about 1 min or less. The places of observations of high doses due to relativistic electrons are distributed mainly at latitudes above 50° geographic latitude in both hemispheres on Foton M2/M3 satellites. A very high maximum is found in the southern hemisphere at longitudinal range 0°–60°E. At the ISS the maximums are observed between 45° and 52° geographic latitude in both hemispheres mainly at longitudes equatorward from the magnetic poles. The measured absolute maximums of dose rates generated by relativistic electrons are found to be as follows: 304 μGy h⁻¹ behind 1.75 g cm⁻² shielding at Foton M2, 2314 μGy h⁻¹ behind 0.71 g cm⁻² shielding at Foton M3 and 19,195 μGy h⁻¹ (Flux is 8363 cm⁻² s⁻¹) behind les than 0.4 g cm⁻² shielding at ISS.