Stimulation of plasma waves in the magnetosphere using satellite JIKIKEN (EXOS-B)

The stimulated plasma wave experiment (SPW) has been successfully carried out in the plasmasphere and the magnetosphere along the JIKIKEN (EXOS-B) satellite orbit where the plasma parameters indicate wide variety of the combination of the electron number density, ranging from 1/cc to 10⁴/cc, and the electron cyclotron frequency, ranging from 6 kHz to 200 kHz.The upper hybrid resonances F_UHR usually persists for long periods up to 125 msec and the electron cyclotron resonances nF_H are stimulated at frequencies with the very high harmonic number n; sometimes, the nF_H resonance takes place for n=47.All the features of the resonances including F_On reflect the characteristics of the magnetospheric plasma that contains the energetic and non-Maxwellian components of the particles. The measurement of the plasma resonance contributes to the detection of the local electron density and the magnetic field intensity. The mode of the propagating radio waves is also determined being compared with the observed local plasma resonance frequency F_p.     

VLF transmissions from Kajford (Norway) to Scatha

The University of Paris and The Aerospace Corporation performed the injection of VLF waves into the magnetosphere from Norway to Scatha. The first transmissions took place in May, 1979. The transmitted signal was either a 1280 Hz keyed-fixed frequency or a continuous wave, sweeping linearly from 1350 Hz to 2550 Hz. Signals correlated with the transmissions were recorded on May 26 and May 27.     

Non-linear magnetospheric amplification of VLF transmissions

Non-linear amplification of a monochromatic VLF transmission in the magnetosphere produces an output fluctuating in amplitude and phase, and so is not monochromatic. This output can usually be resolved into two waves: one similar to the input, but stronger, and a higher frequency sideband or “embryo emission”. The established theory is outlined as far as it goes.     

In situ Lunar Orientation Measurement (ILOM): Simulation of observation

The measurement of the rotation of the Moon is one of the key techniques to get the information of the internal structure. For this purpose, we proposed a small telescope experiment on the surface of the Moon in which motion of stars are utilized for the estimation of the rotation parameter. This paper describes results of simulation of observation, in which star trajectories observed are decomposed to librations, polar motion, and the precession and the amplitude and phase of each component are estimated. The standard deviation of the parameter estimation becomes nearly 1 ms of arc, which will be better than the Lunar Laser Ranging observation. From the viewpoints of accuracy of observation, thermal condition, and electric power generation, the instrument should be placed where the much sunshine is achieved on the lunar polar region.     

Selection of sensors and spectral bands of marine observation satellite (MOS) — 1

After trading off the proposed requirements by the Committee on Earth Observation Satellite Development, cost and time for development of sensors, spacecraft and launch vehicle, the following sensors were selected for Marine Observation Satellite (MOS) - 1.(1) Four channel visible and near IR sensor (MESSR) with 50 meter resolution. (2) Four channel visible and thermal IR sensor (VTIR) with 0.9 km (visible) and 2.7 km (IR) resolution respectively. Out of three IR channels, two channels are atmospheric window channels while the third channel is water vapor absorption band. (3) Two channel microwave scanning radiometer (MSR) with responsivity in 23.8 and 31.4 GHz respectively. (4) Data collection system.     

Comparison of NMC model calculated longwave flux with satellite (ERBE and AVHRR) observation

The U.S. Air Force Real Time Nephanalysis (RT NEPH) is incorporated into the NMC Medium Range Forecast Model (MRF) to explore the impact of cloudiness on the model's radiation parameterization. After transfering to MRF model coordinate, RT NEPH is in qualitative agreement with ERBE Scene ID. The zero-hour “forecast” of outgoing longwave radiation (OLR) of 00GMT Nov. 9, 1984 is compared with that derived from NOAA AVHRR observation and the preliminary ERBE result. The comparison shows that the greater difference in OLR are from cloudy sky regions, in spite of qualitative agreement on the structures. The result suggests that for proper simulation of OLR, a refinement of the model cloud parameterization or nephanalysis on the prescribed data would be more effective than on radiative transfer scheme.     

Planned observation of Phobos/Deimos by Mars imaging camera (MIC) on NOZOMI

The large elongated orbit planned for NOZOMI around Mars, i.e. a periapsis of 150 km and an apoapsis of 15 R_M (R_M denotes the radius of Mars), will provide many occasions for encounters of NOZOMI with two Martian satellites, Phobos and Deimos, where NOZOMI is the former Planet-B meaning “Hope” in Japanese. We present a plan for imaging the two satellites by the Mars Imaging Camera (MIC) on board NOZOMI at such encounters during the mission lifetime of two years from October 1999. An Autonomous Tracking Mode is available for fly-by imaging of satellites. MIC scans the azimuth direction (orthogonal to the CCD line arrays) using the spacecraft spin at a rotation rate of 7.5 rpm, and has an image resolution of 80 arc second in both elevation and azimuth directions.The main science objectives of MIC, related to the two satellites, are (i) to study the size/spatial distributions of craters on both satellites, (ii) to examine the groove structure on Phobos, (iii) to image areas not yet seen areas of Deimos, and (iv) to derive its whole shape. We will, furthermore, search for the dust rings along the orbits of these two satellites in the forward scattering region of sunlight. The capability of MIC to execute these objectives are briefly summarized.     

Siple VLF transmissions and their magnetospheric effects observed at Halley,Antarctica

Halley (75.5°S, 26.7°W, L = 4.3) is well placed for reception of subionospheric signals from the Siple transmitter. Occasionally a two-hop magnetospheric response to such signals can be observed. The data presented here are relevant to the problems of the radiation and propagation of VLF waves in the polar earth/ionosphere waveguide, duct stimulation and ducted wave amplification and the growth of triggered emissions. An upper sideband emission 20–40 Hz higher in frequency than the transmitted pulse was often received at a similar strength to, and simultaneously with the two-hop whistler mode echo.     

基于X射线脉冲星导航试验卫星观测数据的到达时间估计

中国首颗X射线脉冲星导航试验卫星（X-ray Pulsar Navigation-1, XPNAV-1）搭载了两种体制的X射线探测器,其主要任务是在轨开展X射线脉冲星的探测以及进行脉冲星导航体制的验证。为了实现到达时间（Time of Arrival,TOA）的高精度估计,提出了利用阵列信号处理领域的多重信号子空间分类（Multiple Signal Classification,MUSIC）方法进行脉冲星导航的TOA估计,进行了试验仿真验证,并且对XPNAV-1观测到的蟹状星云（Crab）脉冲星的光子数据进行处理。在观测时间为协调世界时（Coordinate Universal Time,UTC）57727.0约简儒略日（Modified Julian Day,MJD）到UTC57812.0MJD内,选取了0.5~10keV频段内的121段光子观测数据,对这些数据进行了脉冲轮廓折叠,得到了Crab脉冲星的折叠轮廓,然后分别利用互相关法和MUSIC方法进行折叠轮廓的TOA估计,最后对比了两种方法的估计结果。     

Spectroscopic observation of Mars

Visible and near-infrared reflectance spectroscopy has proven a powerful tool for exploring the geology of Mars. Most of this data has been obtained from Earth, but the technique is ideally suited to orbital application, as proposed for the U.S. Mars Geoscience/Climatology Orbiter mission. Spectral reflectance in the near-UV and visible is highly diagnostic of ferric-iron mineralogy, and has shown that Fe³⁺ in the ubiquitous bright dust and soil is amorphous or poorly-crystalline. Other iron-oxide minerals, indicative of other modes or episodes of crustal alteration, may be found in spatially localized deposits. Clay minerals (hydroxylated silicates) have diagnostic vibrational absorptions throughout the near-infrared. While some form of bound water and/or OH has been known on Mars for many years, a new result presented here is the identification of structural OH in a dilute or poorly crystalline magnesian clay. Salts such as carbonates, sulfates, and nitrates have not yet been detected in martian soils but have diagnostic spectral features in the 3- to 4-μm region, best suited to Mars-orbital observation. Analysis of reflectance spectra of low-albedo regions is a primary source of evidence for a basaltic or ultramafic crust, with identification of abundant clinopyroxene and possible detection of other mafic minerals. The distinctive near-infrared spectral shape of dark regions indicates that the dark materials commonly consist of relatively unaltered rocks or rock fragments very thinly coated by (or mixed with) bright oxidized material similar to the global dust. Visible and near-infrared reflectance spectroscopy is also a sensitive technique for detecting and analyzing water ice, as has been demonstrated on Mars by observations of the north polar cap.     

Bi_(1.9)Pb_(0.3)Sr_(2.0)Ca_(1.7)Mg_(0.3)Cu_(3.1)O_x 超导块材弱连接区的低磁场性

通过对在不同外磁场下Ｂｉ１．９Ｐｂ０．３Ｓｒ２．０Ｃａ１．７Ｍｇ０．３Ｃｕ３．１Ｏｘ超导块材的交流磁化率的测量，获得了样品内晶粒间和晶粒内对外场的不问响应范围．通过与粉状样品实验结果的比较和Ｘ光分析，认为块状样品在温度为１００Ｋ左右出现的抗磁台阶是样品内晶粒间超导弱连接的一种抗磁效应．对弱连接区有效钉扎力Ｆｐ和临界电流密度Ｊｃ与外场Ｈ的关系进行了讨论．     

XMM-Newton observation of Vela shrapnel D

The ROSAT all-sky survey discovered several ‘shrapnels’, showing boomerang structures outside the Vela SNR. We observed the shrapnel D in the eastern limb of the Vela SNR with the XMM-Newton satellite. There is an X-ray bright ridge structure in our FOV running from north to south. There is also an optical bright ridge structure running parallel to that in X-ray about 3′ in the east. These suggest that the shrapnel D is now interacting with an interstellar cloud. Applying the VNEI model to X-ray spectra of various regions, we find that the plasma state of the eastern region of the X-ray ridge is significantly different from that of the western region. The X-ray spectra in the western region can be well fitted with a single temperature component. Abundances of heavy elements are almost uniform, whereas they are heavily overabundant (except Fe): the relative abundances to the solar values are O ∼5, Ne ∼8, Mg ∼8, Fe ∼1. It must have originated from the ejecta of the SN. We find that the plasma in the eastern part of the ridge consists of two temperature components: one component (hot plasma) representing the ejecta while the other (cold plasma) represents the interstellar cloud or swept-up ISM. These two components must have contacted to each other, indicating to form a contact discontinuity. Around northern part of the contact discontinuity, we found wavelike structures of which the typical scales are comparable with that of the Rayleigh–Taylor instability.     

Low-latitude ionospheric scintillations and total electron content obtained with the CITRIS instrument on STPSat1 using radio transmissions from DORIS ground beacons

The primary objective of the Scintillation and Tomography Receiver in Space (CITRIS) is to detect ionospheric irregularities from space at low latitude. For this purpose, the satellite receiver uses the UHF and S-Band transmissions of the ground network of Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) beacons. CITRIS, developed at the Naval Research Laboratory, differs from the normal DORIS receiver by being able to capture and store the complex amplitude of the 401.25 and 2036.25 MHz transmissions at 200 Hz sample rate. Ground processing of the CITRIS data yields total electron content (TEC) and both phase and amplitude scintillations. With CITRIS flying on the US Space Test Program (STP) satellite STPSat1, 2 years of data were collected and processed to determine the fluctuations in ionospheric TEC and radio scintillations associated with equatorial irregularities. CITRIS flights over DORIS transmitters yield direct measurements of the horizontal plasma density fluctuations associated with equatorial plasma bubbles. Future flights of CITRIS can provide valuable complements to other satellite instruments such as GPS occultation receivers used to estimate vertical electron density profiles in the ionosphere.     

Hard X-ray observation of galactic X-ray sources

A large (1455 cm²) hard X-ray telescope was successfully launched aboard a stratospheric balloon on October 4, 1980. During this flight four galactic X-ray sources were observed, namely the transient recurrent X-ray pulsar A0535+26, the Crab Nebula, Cygnus X-1 and X Persei. Here we report the results on the latter two sources. From Cygnus X-1 we measured a photon flux in the band 30 to 200 keV, of 3.5 × 10^?2 photons cm^?2 which is 6.5 times lower than that recieved from the source in a “low” intensity state in the same energy band. In addition, the photon spectrum in the same energy band was very soft and consistent with a power law with photon index α = 2.71 ± 0.14. Even if a simultaneous observation of the source at lower energies was not available, our data strongly suggest that we observed the source during a “high” intensity state. We report also positive detection in the band 30 to 200 keV of the low luminosity X-ray pulsar X Persei. In its spectrum we confirm the presence of a hard X-ray tail consistent with a power law (photon index α = 2.17 ± 0.42).     

Millimeter-wave continuum observation of high-z radio quasars

Millimeter-wave continuum observations of high redshift (z3) radio loud quasars (RLQs) and radio intermediate quasars (RIQs) have been performed with the 45 m telescope of the Nobeyama Radio Observatory. Sixteen RLQs with S_5GHz > 200 mJy and nine RIQs with 200 mJy > S_5GHz > 20 mJy were observed at four millimeter-wave frequencies. All the observed quasars have synchrotron spectra and their possible dust emission component is obscured by the synchrotron emission in millimeter-wave frequencies, which can be explained by their strong AGN activities. Observed quasars are classified into three spectral classes, according to their millimeter-wave spectral index as steep spectrum, millimeter turn over and extreme flat spectrum quasars. Extreme flat spectrum quasars have relatively flat spectra up to 150 GHz, where the rest frequency is higher than 600 GHz. This is an indication that the objects are in very young stage of quasar evolution and shows higher nuclear activity than lower redshift quasars. One of the QSOs, 2358+189 previously known as a RIQ, is found to have extreme flat spectrum, and is now classified as RLQs.     

非晶态（Fe0.5Ni0.5）80—xCrxP14B6合金薄带的磁谱的研究

以阻抗电桥法对非晶态(Fe_(0.5)Ni_(0.5))_(80-z)Cr_zP_(14)B_6(x=0,1,2,3,4,6,10)合金薄带的淬态和等温退火后样品的磁谱进行了测量。结果表明:退火后相对起始磁导宰μ_(?)提高了3.6～6倍,截止频率f_c下降,磁损耗μ_2的磁谱出现了共振峰。同时,等温退火处理对各样品相对起始磁导率的影响比改变Cr元素含量x要大得多。     

非晶态(Fe_(0.5)Ni_(0.5))_(80-x)Cr_xP_(14)B_6合金的内禀磁性和热稳定性的研究

对Cr含量变化对非晶态(Fe_(0.5)Ni_(0.5))_(80-x)Cr_xP_(14)B_6(x=0,1,2,3,4,6,10)合金薄带样品的内禀磁性和热稳定性进行了研究。对所得的随着Cr含量增加,样品的磁性原子的平均磁矩(?)和居里温度T_c的减少,热稳定性的提高等结果进行了讨论。当Cr含量x=4at％时,样品表现出一些特殊性质;而当x>4at％和<4at％时,样品的磁性和热稳定性的变化不尽相同。     

Rocket observation of the near-infrared extragalactic background radiation

Near-infrared diffuse radiation at 1 μm – 5 μm was observed using cold optics on board a sounding rocket. The observed surface brightness is too bright to be explained by known diffuse sources and its significant part is possibly attributed to the cosmic origin. Extragalactic background radiation thus obtained is brighter than theoretically estimated so that new energy sources at an early epoch of the universe are required.     

Zodiacal light and space observation of faint objects

Zodiacal light is examined as a “foreground noise” limiting the space photometry of faint objects. Emphasis is given to the ways of increasing the signal to noise ratio by an appropriate choice of observational epoch. In the case of the Space Telescope, predictions of average values of this ratio for the extreme faintness case V = 28 are derived from the expected performances announced by NASA and from the recent table of zodiacal brightnesses, as obtained from observations at Tenerife ([1], table 2).     

Direct observation of processes in a solidifying dispersion

The evolution of a dispersion under the action of temperature gradients and solidification was followed optically in a transparent molten salt (CsCl) with inclusions of Pb-droplets and gas bubbles. This system is believed to model a solidifying metallic alloy. Rejection of Pb-particles by the solidification front was observed, while large gas bubbles were incorporated. Thermocapillary convection at the gas bubbles considerably distorted the temperature field and even caused local remelting. Marangoni migration of bubbles was not observed, contrary to expectations.