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591.
H.D.R. Evans P. Bühler W. Hajdas E.J. Daly P. Nieminen A. Mohammadzadeh 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,42(9):1527-1537
The Standard Radiation Environment Monitor (SREM) is a simple particle detector developed for wide application on ESA satellites. It measures high-energy protons and electrons of the space environment with a 20° angular resolution and limited spectral information. Of the ten SREMs that have been manufactured, four have so far flown. The first model on STRV-1c functioned well until an early spacecraft failure. The other three are on-board, the ESA spacecraft INTEGRAL, ROSETTA and PROBA-1. Another model is flying on GIOVE-B, launched in April 2008 with three L-2 science missions to follow: both Herschel and Planck in 2008, and GAIA in 2011). The diverse orbits of these spacecraft and the common calibration of the monitors provides a unique dataset covering a wide range of B-L* space, providing a direct comparison of the radiation levels in the belts at different locations, and the effects of geomagnetic shielding. Data from the PROBA/SREM and INTEGRAL/IREM are compared with existing radiation belt models. 相似文献
592.
We propose a method that makes it possible to obtain in the framework of linear approximation the exact formulas for the wave resistance of the channel walls with an arbitrary plane pattern in the first and subsequent interference zones. It is shown by a particular example of the sinusoidal pattern that the pressure wave interference may lead to the positive or negative resistance resonance. 相似文献
593.
S. Seetha M.C. Ramadevi V.C. Babu M.R. Sharma N.S.R. Murthy B.N. Ashoka K.C. Shyama R. Kulkarni G. Meena P. Sreekumar 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2995-2998
The Scanning Sky Monitor is one of the experiments onboard the ASTROSAT, an Indian multiwavelength astronomy satellite mission. This experiment will detect and monitor X-ray transients in the energy band 2–10 keV. It is similar in design to the ASM on RXTE. It consists of position-sensitive proportional counters with one-dimensional mask. We describe the configuration of the experiment. We also discuss some of the results obtained using a detector which has already been fabricated and tested in our laboratory. 相似文献
594.
Information Support for Space Experiments Based on a Numerical-Analytical Theory of Satellite Motion
A software tool for application in calculations of the position and velocity vectors of spacecraft is presented. These vectors are necessary at the stage of processing the data of space experiments and analyzing the results of ground-based observations. A new theory of satellite motion, in a numerical-analytical form, is the basis of this software application. The model of disturbing forces corresponds to recommendations of the International Laser Ranging Service. The reliability of the software tool is confirmed by the results of processing of high-precision laser satellite observations. 相似文献
595.
R E Fortson J C Sager P V Chetirkin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1994,14(11):327-330
The Biomass Production Chamber (BPC) at the Kennedy Space Center is part of the Controlled Ecological Life Support System (CELSS) Breadboard Project. Plants are grown in a closed environment in an effort to quantify their contributions to the requirements for life support. Performance of this system is described. Also, in building this system, data from component and subsystem failures are being recorded. These data are used to identify problem areas in the design and implementation. The techniques used to measure the reliability will be useful in the design and construction of future CELSS. Possible methods for determining the reliability of a green plant, the primary component of a CELSS, are discussed. 相似文献
596.
J W Wilson L W Townsend J L Shinn F A Cucinotta R C Costen F F Badavi S L Lamkin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1994,14(10):841-852
The development of the theory of high charge and energy (HZE) ion transport is reviewed. The basic solution behavior and approximation techniques will be described. An overview of the HZE transport codes currently available at the Langley Research Center will be given. The near term goal of the Langley program is to produce a complete set of one-dimensional transport codes. The ultimate goal is to produce a set of complete three-dimensional codes which have been validated in the laboratory and can be applied in the engineering design environment. Recent progress toward completing these goals is discussed. 相似文献
597.
T G Guzik S Albergo C X Chen S Costa H J Crawford J Engelage P Ferrando I Flores L Greiner F C Jones C N Knott S Ko P J Lindstrom J Mazotta J W Mitchell J Romanski R Potenza A Soutoul O Testard C E Tull C Tuve C J Waddington W R Webber J P Wefel X Zhang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1994,14(10):825-830
The Transport Collaboration, consisting of researchers from institutions in France, Germany, Italy and the USA, has established a program to make new measurements of nuclear interaction cross sections for heavy projectiles (Z > or = 2) in targets of liquid H2, He and heavier materials. Such cross sections directly affect calculations of galactic and solar cosmic ray transport through matter and are needed for accurate radiation hazard assessment. To date, the collaboration has obtained data using the LBL Bevalac HISS facility with 20 projectiles from 4He to 58Ni in the energy range 393-910 MeV/nucleon. Preliminary results from the analysis of these data are presented here and compared to other measurements and to cross section prediction formulae. 相似文献
598.
C. S. Wu 《Space Science Reviews》1985,41(3-4):215-298
This article reviews the theory of the kinetic (cyclotron an synchroton) maser instabilities. The subject has been extensively developed in recent years by many authors, who have been incited by the research of the auroral kilometric radiation and other applications. The maser mechanism is appealing because it is simple and efficient, and can lead to direct amplification of radiation. Two types of electron distribution functions have been investigated so far. These are the loss-cone and hollow-beam distributions which may exist pervasively in many regions within and beyond the solar system. It is likely that the maser instabilities can have many potentially important applications to numerous radio emission processes observed in astrophysical research. 相似文献
599.
P. Ubertini A. Bazzano L. Boccaccini N.A. Dipper L. Iafrate C. LaPadula M. Mastropietro R. Patriarca V. Polcaro M.L. Urciuoli 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(1):105-108
A new design of position sensitive spectroscopic proportional counter is described, for use in a balloon borne hard x-ray telescope. Initial position and spectral resolution data from a one-dimensional laboratory prototype are reported. With this device, the final telescope will have an angular resolution of better than 10 minutes of arc. 相似文献
600.
T.K. Yeoman H.C. Scoffield D.M. Wright L.J. Baddeley A.N. Vasilyev N.V. Semenova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
A brief review is provided of recent progress in understanding the ionospheric Alfvén resonator (IAR) at high latitude. Firstly, naturally occurring resonances of the IAR as detected by pulsation magnetometers in the auroral zone at Sodankylä and in the polar cap at Barentsburg are considered. The characteristics of the IAR in the two regions are broadly similar, although the effects of solar illumination are less clear at the higher latitudes. Secondly we review recent attempts to stimulate the IAR through high-power radio frequency experiments both in the auroral zone at Tromsø with the European Incoherent SCATter (EISCAT) heater, and within the polar cap at Longyearbyen with the Space Plasma Exploration by Active Radar (SPEAR) facility. In the auroral zone at, Tromsø the stimulated IAR has been observed by ground-based magnetometers, and through electron acceleration observed on the FAST spacecraft. At SPEAR in the polar cap, the stimulated IAR has been investigated, with ground magnetometers, with the first results indicative of a positive detection. 相似文献