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1.
Amateur spectroscopists are getting organized to contribute to professional astronomy work. We present here the work done within the AUDE association to design, manufacture and distribute the Lhires III high-resolution Littrow spectrograph, which fits usual amateur telescopes and CCD cameras. We also review how the communication is organized through the ARAS distribution list (Spectro-L), forums, and workshops to develop and promote spectroscopic work among amateurs. Last but not least, we introduce the Be stars spectra (BeSS) Virtual Observatory-compatible database and its use for the monitoring of Be stars in association with the COROT satellite.  相似文献   
2.
在几种适合用来对面天体进行分光测量的仪器中,积分视场光谱仪(Integral Field Spectrograph,IFS)因为能同时获得面源的光谱信息而备受关注.基于对IFS的初步研究,在实验室中进行光纤式IFS实验,取得一定进展后再将实验设备用于云南天文台2.4 m望远镜,对特定的天体进行测量,从而为科学级IFS的...  相似文献   
3.
波长位置在光谱工作中至关重要。本文讨论和介绍了利用恒星光谱谱线、夜天光谱线、大气吸收线及摄谱仪标准谱灯谱线确定波长位置的方法。  相似文献   
4.
The impulsive phase of the 23 July 2002 2B/X4.8 proton flare with a classical two-ribbon structure was observed with the Irkutsk Large Solar Vacuum Telescope (LSVT) in spectropolarimetric mode, with high spatial, spectral, and time resolution. On the basis of 49 spectrograms and 1200 spectral cuts across the flare ribbons, evidence for Hα line impact polarization has been obtained. A systematic change of the Stokes Q and U parameters has been detected across the ribbons for different flare regions measured with a scanning step of 0.85″. In the eastern side of the ribbons, the degree of polarization is 4 – 8%; its plane is oriented toward the solar disk center (radial direction). In the western side, the polarization degree runs up to 25%, and its plane is perpendicular to the disk center direction (tangential direction). A comparison of these results with hard X-ray data (RHESSI) allows us to conclude that high-energy electron beams reached the chromosphere during this flare. The observed changes of the direction of polarization and the vanishing polarization within the ribbons mean that, at the chromospheric level, the energy of electrons remaining in the beam is about 200 eV. A shift of the peak position of polarization relative to the intensity maximum in the ribbons may result from the inclination of the electron beam axis with respect to the solar surface.  相似文献   
5.
We describe a design for a compact cooled spectrograph which incorporates two cameras and two collimators to achieve high throughput from 0.8 to 2.5m. The spectrograph utilizes multiple NICMOS 3 arrays, specially mounted to minimize their separation in the spectral dimension. This accommodates the broad wavelength range while providing extensive coverage in the spatial dimension.  相似文献   
6.
The WIYN 3.5-meter telescope and its Multi-Object Spectrograph (MOS) have been used to obtain simultaneous spectra at many points in the coma of Comet Hale-Bopp. Between 1996 October and 1997 April in excess of 7500 individual spectra were obtained, typically 96 at a time. On six nights the “Hydra” fiber positioner was used to sample a ring pattern of points about the nucleus with a minimum spacing of 40 arc seconds and a maximum radius of 22.5 arc minutes. On four nights a new “Densepak” fiber cable was used. In this configuration a 7 × 13 rectangular pattern of 91, 3 arc second fibers on 4 arc second centers was used. In most cases the bench spectrograph was used in the echelle mode with an interference filter to isolate a single order. The wavelength range from 6100 Å to 6400 Å was recorded with resolution of approximately 15,000. This spectral region contains the emission features of [OI], C2, NH2and H2O+. From this mass of data we are beginning to extract the radial, azimuthal and temporal variations of many different spectral features. The radial profiles of [O I] λ6300 Å and NH2 are reasonably well representable by the Haser model formalism, that of H2O+ is not.  相似文献   
7.
光谱仪是1 m太阳望远镜的主要终端设备之一,该望远镜采用地平式的机架结构和修正的格里高利光学系统。在望远镜跟踪太阳时,由于地平式望远镜的自身运动特点和光学系统中平面反射镜的存在,其光谱仪狭缝所在平面上的太阳像随时间绕主光轴旋转,因此光谱仪必须进行消旋才能正常工作。首先深入研究了光谱仪狭缝平面上像的旋转变化,分析其旋转范围、速度和加速度随时角变化的特性,然后根据光谱仪消旋精度并结合像的旋转特性提出伺服系统位置检测和驱动电机的主要性能指标,最后给出光谱仪消旋伺服控制方案。  相似文献   
8.
We describe the multislit spectrograph SFM. It is designed to obtain simultaneously spectrograms of faint objects over a field of 10 arcminutes for an entrance aperture ratio f/10, or of 15 arcmin for f/8. The SFM makes the dispersed image of the entrance slits directly, without any fiber optics. The number of entrance slits can be as large as a few hundreds, depending on the distribution of the sources on the sky and on the wavelength range. The present reciprocal dispersion is 79Åmm–1 in the wavelength range 3600 – 6400Å. The SFM is expected to reachm v22 with a signal to noise ratio of 10 for a spectral resolution of 3.3Å and an integration time of 5 hours, when used with the photon counting detector CP40.Radial velocities can be measured either by using calibration spectrograms or by the objective prism technique.The mask of entrance slits is made photochemically from a plate previously recorded of the field to be observed, taken during the same observing run. The auxiliary equipment Mascograph, specially designed for this purpose, is described.First spectrograms in the field of M15 obtained with the SFM using the Calar-Alto 3.50m telescope are presented.Based on observations collected at the Calar-Alto 3.5m telescope, operated by the German MPIfA (Heidelberg), and at the 3.60m CFHT, operated jointly by the Canadian SRC, the French CNRS and the University of Hawaii  相似文献   
9.
简要介绍了用于研究分子夭文学的各种射电频谱仪及国内外发展状况,讨论了各种频谱仪的优缺点,最后提出了云台建立射电频谱仪的型式。  相似文献   
10.
讨论了如何将SOPC技术用于大天区多目标光纤光谱天文望远镜(LAMOST)项目的低分辨率光谱仪IP控制核的设计,并在NIOSⅡ软核基础上设计实现了光谱仪IP控制核。整个IP控制核主要分为底层电机控制单元和通信单元两部分。通过工业以太网,远程控制计算机可以方便地控制低分辨率光谱仪,使其完成指定动作。也可以从本地控制计算机上实行控制。设计中采用将步进电机控制器封装成IP再复用的方法,大大缩短了研发时间,减少错误的发生。通信控制中串口通信和以太网可以互为冗余,保证了通信的顺利进行。  相似文献   
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