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《天文学报》2017,(4)
在恒星干涉仪中,高速倾斜镜(Fast-steering mirror,FSM)因分辨率高、响应频率快等特点被广泛应用于校正大气湍流、仪器内部振动等引起的波前倾斜.一方面,针对倾斜镜本身在加工、装调中引入的镜面与触动器偏转轴不共面等误差进行系统分析,通过数值方法研究了上述因素在倾斜镜工作时产生的附加光程差(Optical Path Difference,OPD),并讨论了该光程差对恒星干涉仪条纹跟踪精度的影响;另一方面,两臂光束之间的平行度误差是造成干涉条纹可见度损失的主要因素之一,通过分析大气扰动引起的波前倾斜对条纹可见度的影响,提出了一种基于单一阵列探测器、简单高效的星光平行度实时校正方案,并结合室内实验论证了该方案的可行性.实验结果表明:经高速倾斜镜校正后的星光方向平行度初步满足了恒星干涉仪系统对波前倾斜的需求. 相似文献
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本文介绍1.26米红外望远镜出厂后的主要误差,用谐波分析法分离望远镜的各项主要误差(2~m显示误差,4~m17~5短周期跟踪误差以及长周期跟踪误差等),讨论误差产生原因,计算由这些原因引起的误差理论值,并与实测值进行比较,分析其对望远镜使用精度的影响,叙述消除误差的方法及实际效果。 相似文献
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双向卫星时频传递系统与应用 总被引：2，自引：0，他引：2
系统地阐述了双向卫星时频传递（TWSTFT）系统的原理、误差因素和结构实现，对系统的模块、流程操作进行了说明，并介绍了TWSTFT在国家授时中心的应用，最后提出了TWSTFT在我国的发展设想。 相似文献
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利用数值模拟方法产生一定巡天极限星等下的模拟星系样本,并加入测光误差,来考虑对功率谱计算的影响。在处理有限流量样本时,发现会引进功率谱的系统误差,而有限体积样本则可以很好地消除这种影响。在处理有限流量样本时,若巡天极限星等为20．5^m,在100－1000h^-1Mpc尺度,要求测光误差小于0．1^m,这时由测光误差引起的功率谱误差远小于由于巡天体积和星系数密度引起的功率谱的随机误差,因此可以忽略测光误差的影响。 相似文献
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本文利用模拟观测资料，估计了中国卫星跟踪网对近地测地卫星定轨和测定一些跟踪站地心坐标所能达到的精度。同时分析了近地卫星定轨的主要误差源，如大气模型、地球引力场模型的不确定性和跟踪网站坐标的误差等所产生的影响。 相似文献
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在统计轨道理论的框架下分析多种技术资料的综合处理方法的精度．提出除了拟合剩余残差的ＲＭＳ外,皮尔逊（Ｐｅａｒｓｏｎ） χ２ 统计量和高阶矩也应作为判断解算好坏的重要指标．初步探讨了利用这些统计量评价不同技术间的相对权因子给定问题．作为对系统差来源的初步探索,利用考察协方差分析理论分析了考察参数误差对解算的影响,讨论了考察协方差与相对权因子的关系 相似文献
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在单轴晶体光轴任意取向的情形下应用惠更斯原理导出了双折射滤光片产生位相差的精确公式,结合几种熟知的特殊情形进行了简要讨论,给出完全一致的相关结果,揭示该普遍公式的正确性.针对光轴标定误差小的晶片,对普遍公式进行相应的近似,进一步分析了晶片定轴误差对宽视场双折射滤光器视场的影响,说明引入适当的光轴定向微扰误差可以增大滤光器某一方位角处的视场. 相似文献
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The method of stellar radial velocity variations has recently shown its capability by the first discovery of several extra-solar planets. Accuracies achieved today are in the range 3-10 m/s. The AAA (absolute astronomical accelerometer) is an instrument which aims to reach the photon noise limit for the measurement of velocity changes, with systematic errors of about 1 m/s, long term. The principle is to use a servo-controlled CCD spectrograph as a null detector, and to register always the lines of the star on the same CCD pixels. Thus, systematic errors linked to the Earth-induced large variations are cancelled. A tunable Fabry-Perot channelled spectrum is also following the star spectrum, while the FP thickness is measured by heterodyne detection of the beats between a tunable laser diode and a stabilized laser diode. A complete prototype of the instrument is operating with laboratory sources and the first results are presented. It is planned to use this system with a new spectrograph, to be coupled to the 152 cm telescope at Observatoire de Haute Provence. 相似文献
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John Meaburn 《Astrophysics and Space Science》1975,36(2):489-493
The performance of an image-tube insect-eye Fabry-Perot spectrograph is compared to a classical Fabry-Perot monochromator when used on some topical nebular problems. 相似文献
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G. A. Chountonov 《Astrophysical Bulletin》2011,66(4):496-498
We discuss the possibility of using a Fabry-Perot interferometer as a source of the comparison spectrum for calibrating the
wavelengths in the spectra of astronomical objects. For low dispersion, a Fabry-Perot etalon has been made in the form of
a three-layer structure by sputtering a glass substrate in vacuum in the following order: firstly, a thin translucent layer
of aluminum, then a layer of several micronthick glass, and another layer of semitransparent aluminum. For high dispersion,
a Fabry-Perot etalon has been made of mica several tens of microns thick, the surface of which was sputtered with translucent
coatings of aluminum. In the second case, the density of transmission peaks is higher than the density of intense spectral
lines of thorium by a few dozen times. 相似文献
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H. Sugai T. Usuda H. Kawabata M. Y. Inoue H. Kataza M. Tanaka 《Experimental Astronomy》1994,3(1-4):315-316
We have developed a near-infrared Fabry-Perot imager at the Nasmyth focus of the Communications Research Laboratory (CRL) 1.5 m telescope at Tokyo. Using this wide field Fabry-Perot imager, we obtained continuum-subtracted images of the H2
v=1–0 S(1) line for the Orion KL region. 相似文献
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We describe a software package used at the Special Astrophysical Observatory of the Russian Academy of Sciences to reduce and analyze the data obtained with the Fabry-Perot scanning interferometer. We already described most of the algorithms employed in our earlier paper [1]. In this paper we focus on extra procedures required in the case of the use of a high-resolution Fabry-Perot interferometer: removal of ghosts and measurement of the velocity dispersion of ionized gas in galactic and extragalactic objects. 相似文献
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D. Rees A.H. Greenaway R. Gordon I. McWhirter P.J. Charleton Åke Steen 《Planetary and Space Science》1984,32(3):273-285
During December 1982, a novel Fabry-Perot interferometer—a Doppler Imaging System (DIS)— was used at Kiruna Geophysical Institute (KGI), Sweden (67.8°N, 21.2°E) to complement a series of coordinated observations of global thermospheric dynamics utilizing a number of conventional ground-based Fabry-Perot interferometers and the NASA Dynamics Explorer satellite. The DIS is an interferometer with two unique attributes : it has a luminosity or étendue more than one hundred times that of the conventional Fabry-Perot interferometer, and it is also capable of deducing a two-dimensional velocity field of a suitable line-emitting areal source by independently measuring the Doppler shift at a large number of points within the field of view. On 17 December 1982, a very large geomagnetic Storm Sudden Commencement (08.05 U.T.) preceded a major geomagnetic disturbance. During this disturbance, Northern Scandinavia was influenced by a strong eastward auroral electrojet for an extended period (10–19 U.T.). The DIS was able to observe the dynamical response of the upper thermosphere to this event in conjunction with a second Fabry-Perot interferometer (FPI) at KGI. Westward thermospheric winds of about 900 m s?1 occurred during the disturbance and, at the peak of the disturbance, the combined DIS and FPI observations indicate that the thermospheric flow was quite chaotic. Fluctuations of the order of ± 150 ms?1, associated with spatial scales of the order of 100 or 200 km occurred within the mean westward flow inside the 800 km diameter region observed from Kiruna. 相似文献
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A Fabry-Perot interferometer is being used for two-dimensional spectropolarimetric measurements. We demonstrate the suitability of the setup for the measurement of the magnetic field and present some preliminary results from first observations. 相似文献
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Line shifts occurring on Fabry-Perot interferograms of four limb prominences obtained at Boyden Observatory are reported and analyzed in terms of mass motions of the emitting parts of the prominences. The contribution of these motions to the energy balance of prominences is discussed. 相似文献
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Vincent J. Abreu 《Planetary and Space Science》1985,33(9):1049-1055
The theoretical development of a technique to recover velocities measured with a Fabry-Perot interferometer in the presence of scattered light is presented. Simulations are carried out which show that the inversion is effective in recovering actual velocities, especially in instances when the observed brightness is dominated by scattered light. 相似文献
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Fabry-Perot interferometric observations of the λ5303 Å corona line on 22 September, 1968 were carried out. There are many elements of the interferometric rings with considerable line of sight velocities. The influence on the results of the changes in the brightness of the monochromatic and white-light corona were discussed. 相似文献