共查询到20条相似文献,搜索用时 0 毫秒
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A. Raja Bayanna Shibu K. Mathew P. Venkatakrishnan N. Srivastava 《Solar physics》2014,289(10):4007-4019
The Multi-application Solar Telescope is a 50 cm off-axis Gregorian telescope that has been installed at the lake site of Udaipur Solar Observatory. For quasi-simultaneous photospheric and chromospheric observations, a narrow-band imager has been developed as one of the back-end instruments for this telescope. Narrow-band imaging is achieved using two lithium niobate Fabry–Perot etalons working in tandem as a filter. This filter can be tuned to different wavelengths by changing either voltage, tilt, or temperature of the etalons. To characterize the etalons, a Littrow spectrograph was set up in conjunction with a 15 cm Carl Zeiss Coudé solar telescope. The etalons were calibrated for the solar spectral lines Fe i 6173 Å, and Ca ii 8542 Å. In this work, we discuss the characterization of the Fabry–Perot etalons, specifically, the temperature and voltage tuning of the system for the spectral lines proposed for observations. We present the details of the calibration set-up and various tuning parameters. We also present solar images obtained using the system. 相似文献
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Shibu K. Mathew Ankala Raja Bayanna Alok Ranjan Tiwary Ramya Bireddy Parameswaran Venkatakrishnan 《Solar physics》2017,292(8):106
The Multi-Application Solar Telescope is a 50 cm off-axis Gregorian telescope recently installed at the Udaipur Solar Observatory, India. In order to obtain near-simultaneous observations at photospheric and chromospheric heights, an imager optimized for two or more wavelengths is being integrated with the telescope. Two voltage-tuneable lithium-niobate Fabry–Perot etalons along with a set of interference blocking filters have been used for developing the imager. Both of the etalons are used in tandem for photospheric observations in Fe i 6173 Å and chromospheric observation in H\(\alpha\) 6563 Å spectral lines, whereas only one of the etalons is used for the chromospheric Ca II line at 8542 Å. The imager is also being used for spectropolarimetric observations. We discuss the characterization of the etalons at the above wavelengths, detail the integration of the imager with the telescope, and present a few sets of observations taken with the imager set-up. 相似文献
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Jongchul Chae Hyung-Min Park Kwangsu Ahn Heesu Yang Young-Deuk Park Jakyoung Nah Bi Ho Jang Kyung-Suk Cho Wenda Cao Philip R. Goode 《Solar physics》2013,288(1):1-22
For high resolution spectral observations of the Sun – particularly its chromosphere, we have developed a dual-band echelle spectrograph named Fast Imaging Solar Spectrograph (FISS), and installed it in a vertical optical table in the Coudé Lab of the 1.6 meter New Solar Telescope at Big Bear Solar Observatory. This instrument can cover any part of the visible and near-infrared spectrum, but it usually records the Hα band and the Ca ii 8542 Å band simultaneously using two CCD cameras, producing data well suited for the study of the structure and dynamics of the chromosphere and filaments/prominences. The instrument does imaging of high quality using a fast scan of the slit across the field of view with the aid of adaptive optics. We describe its design, specifics, and performance as well as data processing 相似文献
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A magnetograph is an instrument which makes measurement of solar magnetic field by measuring Zeeman induced polarization in
solar spectral lines. In a typical filter based magnetograph there are three main modules namely, polarimeter, narrow-band
spectrometer (filter), and imager(CCD camera). For a successful operation of magnetograph it is essential that these modules
work in synchronization with each other. Here, we describe the design of instrument control system implemented for the Solar
Vector Magnetograph under development at Udaipur Solar Observatory. The control software is written in Visual Basic and exploits
the Component Object Model (COM) components for a fast and flexible application development. The user can interact with the
instrument modules through a Graphical User Interface (GUI) and can program the sequence of magnetograph operations. The integration
of Interactive Data Language (IDL) ActiveX components in the interface provides a powerful tool for online visualization,
analysis and processing of images. 相似文献
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A. R. Bayanna B. Kumar R. E. Louis P. Venkatakrishnan S. K. Mathew 《Journal of Astrophysics and Astronomy》2008,29(1-2):353-357
A low-order Adaptive Optics (AO) system is being developed at the Udaipur Solar Observatory and we present in this paper the status of the project, which includes the image stabilization system and calibration of wavefront sensor and deformable mirror. The image stabilization system comprises of a piezo driven tip-tilt mirror, a high speed camera (955 fps), a frame grabber system for sensing the overall tilt and a Linux based Intel Pentium 4 control computer with Red Hat Linux OS. The system operates under PID control. In the closed loop, an rms image motion of 0.1–0.2 arcsec was observed with the improvement factor varying from 10–20 depending on the external conditions. Error rejection bandwidth of the system at 0 dB is 80–100 Hz. In addition to that, we report the on-going efforts in the calibration of lenslet array and deformable mirror for sensing and correcting the local tilt of the wavefront. 相似文献
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The theoretical design of the polarimeter used for the Fibre Arrayed Solar Optical Telescope (FASOT) is described. It has the following characteris- tics: (1) It is provided with the function of optical polarization switching, which makes the high-effciency polarimetry possible; (2) In the waveband of 750 nm, the polarimetric effciency is higher than 50% for the every Stokes parameter, and higher than 86.6% for the total polarization, thus an observer can make the simultaneous polarization measurements on multiple magnetosensitive lines in such a broad range of wavelength; (3) According to the selected photospheric and chromospheric lines, the measurement can be focused on either linear polarization or circular polarization; (4) The polarimeter has a loose tolerance on the manufacturing technology of polarimetric elements and installation errors. All this makes this polarimeter become a high-performance polarimetric device. 相似文献
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给出了满足光纤阵列太阳光学望远镜(FASOT,Fibre Arrayed Solar Optical Telescope)观测目标的偏振分析器的理论设计.它具有以下特点:(1)具备偏振光学开关功能,使得高偏振测量成为可能;(2)在750nm宽度范围内,对各Stokes偏振参量都具有50%以上的理论偏振测量效率,且总的偏振测量效率高于86.6%.使得观测者在如此宽波长范围内可对多条磁敏谱线同时进行偏振测量;(3)根据所选光球和色球线侧重于对线偏振或圆偏振的测量;(4)对偏振元件的制作工艺以及安装误差等具有相当好的容忍度.以上特性使该偏振分析器成为高性能的偏振测量设备. 相似文献
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Hyungmin Park Jongchul Chae Donguk Song Ram Ajor Maurya Heesu Yang Young-Deuk Park Bi-Ho Jang Jakyoung Nah Kyung-Suk Cho Yeon-Han Kim Kwangsu Ahn Wenda Cao Philip R. Goode 《Solar physics》2013,288(1):105-116
We observed solar prominences with the Fast Imaging Solar Spectrograph (FISS) at the Big Bear Solar Observatory on 30 June 2010 and 15 August 2011. To determine the temperature of the prominence material, we applied a nonlinear least-squares fitting of the radiative transfer model. From the Doppler broadening of the Hα and Ca ii lines, we determined the temperature and nonthermal velocity separately. The ranges of temperature and nonthermal velocity were 4000?–?20?000 K and 4?–?11 km?s?1. We also found that the temperature varied much from point to point within one prominence. 相似文献
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Xia Zhiguo Cao Ying Chen Jingying Li Weihua Jin Zhenyu Wang Shubao Liu Xiao Wang Min 《天文研究与技术》1999,(Z1)
Ourmeterwavesolarradioacousto -opticalspectrograph(AOS)tracesbacktotheyear 1 979whenitwasbeingbuilt.TheAOScoversaworkingfrequencyrangeof 2 30~ 30 0MHz .Ithasthemeritsofhighspectralresolutionandgoodsensitivity .Thespectralresolution( 0 2 5MHz)de pendsonthecharacteris… 相似文献
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北京天文台对FFS事件的观测研究 总被引:1,自引:0,他引:1
从观测手段和取得的资料两个方面,评价了两个太阳峰年中北京天文台所观测到的太阳射电爆发中毫秒级快速精细结构(FFS)的观测结果.估计了新的观测仪器在第23周峰年将取得的观测结果.也讨论了在观测研究中值得重视的一些问题. 相似文献
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The 1.6 m clear aperture solar telescope in Big Bear is operational and with its adaptive optics (AO) system it provides diffraction limited solar imaging and polarimetry in the near-infrared (NIR). While the AO system is being upgraded to provide diffraction limited imaging at bluer wavelengths, the instrumentation and observations are concentrated in the NIR. The New Solar Telescope (NST) operates in campaigns, making it the ideal ground-based telescope to provide complementary/supplementary data to SDO and Hinode. The NST makes photometric observations in Hα (656.3 nm) and TiO (705.6 nm) among other lines. As well, the NST collects vector magnetograms in the 1565 nm lines and is beginning such observations in 1083.0 nm. Here we discuss the relevant NST instruments, including AO, and present some results that are germane to NASA solar missions. 相似文献
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云南天文台1m红外太阳望远镜是多功能、多波段的太阳望远镜,望远镜使用过程中主镜的热变形直接关系这系统的光学精度,建立光学系统的光机热结合的分析方法,可以直观的得到热辐射对光学系统的影响结果,使得望远镜的设计阶段就能评估热变形对系统的精度影响,确定光学元件是否满足要求. 相似文献
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Lü-Jun Yuan 《中国天文和天体物理学报》2007,7(2):281-288
A new solar telescope system is described, which has been operating at Huairou Solar Observing Station (HSOS), National Astronomical Observatories, Chinese Academy of Sciences (CAS), since the end of 2005. This instrument, the Solar Magnetism and Activity Telescope (SMAT), comprises two telescopes which respectively make measurements of full solar disk vector magnetic field and Hα observation. The core of the full solar disk video vector magnetograph is a birefringent filter with 0.1 bandpass, installed in the tele-centric optical system of the telescope. We present some preliminary observational results of the full solar disk vector magnetograms and Hα filtergrams obtained with this telescope system. 相似文献
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云台红外太阳望远镜中光电导行系统的像场旋转 总被引:1,自引:0,他引:1
红外太阳望远镜中的光电导行系统是高精度的反馈跟踪系统。在开环控制下,难以实现太阳望远镜的跟踪指标,所以必须使用光电导行作为目标位置反馈系统。但是在地平式系统跟踪过程中,光电导行望远镜中的像场会旋转,如果不进行消旋,光电导行系统就不能工作,这就需要解决光电导行系统中的像场旋转。本文在理论上分析了红外望远镜中光电导行系统的像场旋转,并给出了像在CCD面上的运动变化公式。 相似文献
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