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射电观测是太阳物理和日地空间科学的重要探测手段,尤其是对于太阳爆发过程中的太阳非热粒子加速、发射和传播等过程.迄今,世界各地研制建成了上百台太阳射电望远镜,包括射电流量计、射电动态频谱仪和射电日像仪等.基于技术进步和新的科学设想,人们还在不断提出新的太阳射电望远镜计划.研制新的太阳射电望远镜时,需要考虑观测频率、带宽、时间分辨率、频率分辨率、空间分辨率、偏振精度等设计参数.事实上,过度追求高参数往往会无法实现期望的科学目标.如何合理地选择太阳射电望远镜的参数呢?长期的观测研究发现太阳射电爆发常常可分成一系列从长到短不同时标的爆发过程,其中,尖峰爆发是最小时间尺度的爆发现象,同时也是太阳上目前发现的最小空间尺度上的爆发过程,可看成一种元爆发过程,可能对应于单一的磁场重联和磁能释放.根据太阳射电天文学研究,识别尖峰爆发是对新一代太阳射电望远镜的基本要求.尖峰爆发的时间尺度和空间尺度又是随频率而变化的.从分析不同频段太阳射电尖峰爆发的时间和带宽的标度律来说明如何为新一代望远镜的设计选择合理的参数指标,并提出谱-像结合观测模式,最大程度地保证望远镜科学目标的实现.这种观测模式或将成为未来太阳射电观测的主要方式,对揭示太阳爆发现象中的非热过程的物理本质具有非常重要的意义. 相似文献
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《天文研究与技术》1983,(2)
云台射电室的前身是新技术室里的一个小组,1972年开始活动,最初只有2—3人。1975年自行研制成功一台3.2厘米波长的场强仪,在选择太阳射电观测站址和培训技术队伍方面起了一定的作用。1977年安装了波长3.2厘米的太阳射电望远镜(北台研制),开始了太阳射电试观测。1978年经上级决定成立射电天文研究室,同年按照全国天文规划的建议把陕台的太阳射电工作合并到云台,陕台的二台太阳射电望远镜运来云台,其中一台波长8.2厘米的太阳射电望远镜重新安装调试后投入常规观测,直到今日。1979年的电室开始进行声光型太阳射电频谱仪的实验研究,建立了声光实验装置和宽频 相似文献
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本文用云南天文台2902MHz、3653MHz、9375MHz三台射电望远镜的每日射电辐射流量与SMM/ACRIM辐射计测量的太阳常数作相关分析,探讨了太阳缓变辐射流量与太阳常数的关系。 相似文献
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本篇报告给出了9375MHz太阳射电望远镜新定标源系统的结构原理、组装及测试方法,并做到了室内控制。 相似文献
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本文介绍了１５厘米太阳射电望远镜增益运算放大器的结构原理，调试检测及测试结果。 相似文献
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本文强调动态范围是太阳射电望远镜的关键指标．以海淀区青少年科技馆的２１ｃｍ射电望远镜，１９９１年５月１６日及６月１５日的强太阳射电爆发观测资料的频谱和噪声分析结果为例，讨论了其重要性． 相似文献
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本强调动态范围是太阳射电望远镜的关键指标，以海淀区青少年科技馆的２１ｃｍ射电望远镜，１９９１年５月１６日及６月１５日的强太阳射电爆发观测资料的频谱和噪声分析结果为例，讨论了其重要性。 相似文献
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本文介绍了２０００Ｍｃ太阳射电望远镜本机振荡器改造的基本原理，以及本机振荡器的主要技术指标进行检测的结果，结果表明主要技术参数达到了原设计指标。 相似文献
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Tan Bao-lin Cheng Jun Tan Cheng-ming Kou Hong-xiang 《Chinese Astronomy and Astrophysics》2019,43(1):59-74
Radio observation is one of important methods in solar physics and space science. Sometimes, it is almost the sole approach to observe the physical processes such as the acceleration, emission, and propagation of non-thermal energetic particles, etc. So far, more than 100 solar radio telescopes have been built in the world, including solar radiometers, dynamic spectrometers, and radioheliographs. Some of them have been closed after the fulfillment of their primary scientific objectives, or for their malfunctions, and thus replaced by other advanced instruments. At the same time, based on some new technologies and scientific ideas, various kinds of new and much more complicated solar radio telescopes are being constructed by solar radio astronomers and space scientists, such as the American E-OVSA and the solar radio observing system under the framework of Chinese Meridian Project II, etc. When we plan to develop a new solar radio telescope, it is crucial to design the most suitable technical parameters, e.g., the observing frequency range and bandwidth, temporal resolution, frequency resolution, spatial resolution, polarization degree, and dynamic range. Then, how do we select a rational set of these parameters? The long-term observation and study revealed that a large strong solar radio burst is frequently composed of a series of small bursts with different time scales. Among them, the radio spike burst is the smallest one with the shortest lifetime, the narrowest bandwidth, and the smallest source region. Solar radio spikes are considered to be related to a single magnetic energy release process, and can be regarded as an elementary burst in solar flares. It is a basic requirement for the new solar radio telescope to observe and discriminate these solar radio spike bursts, even though the temporal and spatial scales of radio spike bursts actually vary with the observing frequency. This paper presents the scaling laws of the lifetime and bandwidth of solar radio spike bursts with respect to the observing frequency, which provide some constraints for the new solar radio telescopes, and help us to select the rational telescope parameters. Besides, we propose a spectrum-image combination mode as the best observation mode for the next-generation solar radio telescopes with high temporal, spectral, and spatial resolutions, which may have an important significance for revealing the physical essence of the various non-thermal processes in violent solar eruptions. 相似文献
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Recent technical progress of solar radio spectrography is concerned with digital data recording, the achievement of high time and frequency resolution, and with an improved coverage of the radio range at short and long wavelengths. A spatially-distributed network of radio spectrographs allows for complementary information about solar events and periods of activity selected for detailed investigation.By modern radio spectrographs a wealth of not yet adequately classified spectral fine structures can be observed, some of them potentially intimately related to effects of fragmentation of flare energy and/or to processes related to coronal heating. Requirements for the choice of technical parameters of solar spectrographs for checking theoretical models of fundamental processes of energy release are reflected in modern instruments. Prospects for future observations are briefly included. 相似文献
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本文指出了太阳射电快速记录系统中方波隔离放大器研制的必要性，并简要介绍了设计出发点，工作原理，设计特点及主要技术指标的测试 相似文献
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本文介绍了云南天文台微带功率晶体管放大器在太阳射电快速记录系统中的设计原理和技术性能，并给出了放大器的线路图和最初的测量结果。 相似文献
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A new radio spectropolarimeter for solar radio observation has been developed at Tohoku University and installed on the Iitate Planetary Radio Telescope (IPRT) at the Iitate observatory in Fukushima prefecture, Japan. This system, named AMATERAS (the Assembly of Metric-band Aperture TElescope and Real-time Analysis System), enables us to observe solar radio bursts in the frequency range between 150 and 500 MHz. The minimum detectable flux in
the observation frequency range is less than 0.7 SFU with an integration time of 10 ms and a bandwidth of 61 kHz. Both left
and right polarization components are simultaneously observed in this system. These specifications are accomplished by combining
the large aperture of IPRT with a high-speed digital receiver. Observational data are calibrated and archived soon after the
daily observation. The database is available online. The high-sensitivity observational data with the high time and frequency
resolutions from AMATERAS will be used to analyze spectral fine structures of solar radio bursts. 相似文献
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本文主要讨论了太阳射电快速观测记录中可能存在的几种非太阳因素，分析或定量估计了它们的影响，这些因素主要来自天线跟踪效应、接收机增益起伏效应以及地球大气吸收、折射等，估计、分析这些效应对确认太阳射电爆发中的精细结构现象是有益的。 相似文献
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At the Low-Frequency Array (LOFAR)(Planet. Space Sci. (2004) these proceedings) frequencies (HF/VHF), extraterrestrial radiation experiences substantial propagation delay as it passes through the ionosphere. The adaptive calibration technique to be employed by LOFAR will use signals from many known bright radio sources in the sky to estimate and remove the effects of this delay. This technique will operate along many simultaneous lines of sight for each of the stations. Measurements will be made on time scales of seconds or shorter, and with accuracies corresponding to path length variations of 1 cm or less. Tomographic techniques can be used to invert the thousands of changing and independent total electron content (TEC) measurements produced by LOFAR into three-dimensional electron density specifications above the array. These specifications will measure spatial and time scales significantly smaller and faster than anything currently available. These specifications will be used to investigate small-scale ionospheric irregularities, equatorial plasma structures, and ionospheric waves. In addition, LOFAR will improve the understanding of the solar drivers of the ionosphere by simultaneously measuring the solar radio bursts and the TEC. Finally, LOFAR, which will be situated to observed the galactic plane, will make continuous, high-resolution observations of the low-latitude ionosphere, an important but under-observed region. This paper will look at LOFAR as an ionospheric probe including comparisons to other ionospheric probes as well as possible methods of operation to optimize ionospheric measurements. 相似文献
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日冕物质抛射(ChIEs)经常被观测到和其他日面活动相伴生，太阳耀斑、日珥爆发、盔状冕流等许多太阳现象，都与它有直接或间接的关系。射电观测是研究CMEs的一种重要的补充工具。多频率的射电成像观测能很好地研究CMEs的初始阶段，而且可以得到关于CMEs触发机制特征的更多信息。概括了CMEs与低频射电的关系，介绍了低频射电的观测仪器，分析了CMEs低频射电所表现出来的特征，考虑了CMEs的初发机制，总结了尚待解决的问题，表明了CMEs研究是基于多类数据和全电磁辐射波段的。 相似文献