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951.
Low-frequency radio observations offer unique diagnostics of the solar corona and solar wind. After a prolongued hiatus, there is renewed interest in this important frequency regime. Two new ground-based instruments will provide critical new low-frequency observations: the low-frequency array (LOFAR) and the frequency agile solar radiotelescope (FASR). This brief topical review summarizes low-frequency radio phenomena that will be accessible to detailed study by LOFAR and FASR in the coming decade. Energy release, drivers of space weather, and studies of the solar wind are emphasized. Both instruments are expected to play important roles in both basic research problems and national and international space weather capabilities. While FASR is a solar-dedicated instrument, LOFAR is not. Solar observing requirements for LOFAR are briefly discussed. 相似文献
952.
简要介绍了在1988-1995年期间冕洞观测研究的主要进展。文中共分五个方面:1.冕洞磁场观测研究的新进展;2.冕洞在太阳活动周不同位相时的规律性;3.冕洞区高速太阳风观测的新结果;4.冕洞加热问题;5.存在问题。 相似文献
953.
954.
Analysis of ERS-2 scatterometer winds and wind-wave calculation for eastern China seas 总被引:1,自引:0,他引:1
The wind system over the China seas plays an important role in climate variation there. In this paper, ERS-2 scatterometer winds covering the period of 1998 and the area of 25-41°N, 117-130°E were analyzed and compared to NCEP winds and buoy winds in the same period and location, to assess how well the ERS-2 data reflect the real wind regime, at least for this area. The results indicated that ERS-2 scatterometer winds are closer to buoy observations than NCEP winds. In addition, a new wind-wave growth relation was applied to calculate wave parameters. 相似文献
955.
956.
Amongst the sources seen in very high gamma-rays several are associated with Pulsar Wind Nebulae (“TeV plerions”). The study
of hard X-ray/soft gamma-ray emission is providing an important insight into the energetic particle population present in
these objects. The unpulsed emission from pulsar/pulsar wind nebula systems in the energy range accessible to the INTEGRAL satellite is mainly synchrotron emission from energetic and fast cooling electrons close to their acceleration site. Our
analyses of public INTEGRAL data of known TeV plerions detected by ground based Cherenkov telescopes indicate a deeper link between these TeV plerions
and INTEGRAL detected pulsar wind nebulae. The newly discovered TeV plerion in the northern wing of the Kookaburra region (G313.3+0.6
powered by the middle aged PSR J1420-6048) is found to have a previously unknown INTEGRAL counterpart which is besides the Vela pulsar the only middle aged pulsar detected with INTEGRAL. We do not find an INTEGRAL counterpart of the TeV plerion associated with the X-ray PWN “Rabbit” G313.3+0.1 which is possibly powered by a young pulsar. 相似文献
957.
958.
959.
衡山自然保护区森林土壤中动物群落研究 总被引:44,自引:0,他引:44
作者通过一年的定位实验研究,初步阐明了衡山自然保护区森林土壤中动物群落的基本状况。共获得土壤动物30类,隶属于4门11纲,其中弹尾类、蝉螨类和线虫类为优势类群,占全部土壤动物捕获量的92.88%;平均土壤动物密度为67.27万个/m~3;地带性常绿林下发育的黄棕壤中土壤动物密度高达100.47万个/m~3,其次为针阔混交林和针叶林;土壤动物主要分布于森林凋落物层和土壤的腐殖质层中,向下急剧减少;在山地土壤垂直带上,土壤动物随海拔高度而变化。 相似文献
960.
The wave rays and their seasonal variation of stationary and low-frequency Rossby waves are studied by using the Runge—Kutta
scheme. The results show that for stationary waves the rays can reach lower latitudes in winter, and are limited in higher
latitudes in summer. The main differences between the stationary and low-frequency wave rays are that low—frequency waves
can propagate across the equator and the easterlies will not be an obstacle on their propagation. It explained to some extent
the interaction of disturbances between the Northern and Southern Hemispheres. The lower wave frequencies and the stronger
easterly flow are, the more difficult low—frequency waves will be to propagate across the equator. The waves with 20-day period
are easier to propagate across the equator than that with 50—day period. The winter is the most favorable season for low—frequency
waves to propagate into another hemisphere. 相似文献