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1.
宽视场多目标光谱仪具有宽波段、多分辨率模式和高通光效率的特点,是极大望远镜终端仪器使用率最高的通用型仪器. 30 m级望远镜的宽视场多目标光谱仪因体量和成本急剧增加而面临重要挑战,同时天文学的不断发展对天文新技术的发展提出了更高的要求,尤其是多个巡天项目对于多目标光谱后随观测的迫切需求.综述了几类宽视场多目标光谱仪的发展现状,介绍了国际3架30 m望远镜宽视场多目标光谱仪概念设计的最新进展和仪器特点,着重介绍了中国参与研制的30 m望远镜(TMT)中的宽视场多目标光谱仪的相关进展.  相似文献   

2.
8~10m级光学／红外望远镜的高分辨率光谱仪   总被引：1，自引：0，他引：1  
朱永田 《天文学进展》2001,19(2):295-295
介绍并比较了KeckSubaruVLTHET及Gemini中的5架8～10m天文望远镜的高分辨率光谱仪,分析这些仪器与2～4m级望远镜的阶梯光栅光谱仪或Coude光谱仪相比所采用的新设计思想和新技术.  相似文献   

3.
We report the first measurements of radio frequency spectrum occupancy performed at sites aimed to host the future radio astronomy observatory in Indonesia. The survey is intended to obtain the radio frequency interference (RFI) environment in a spectral range from low frequency 10 MHz up to 8 GHz. The measurements permit the identification of the spectral occupancy over those selected sites in reference to the allocated radio spectrum in Indonesia. The sites are in close proximity to Australia, the future host of Square Kilometre Array (SKA) at low frequency. Therefore, the survey was deliberately made to approximately adhere the SKA protocol for RFI measurements, but with lower sensitivity. The RFI environment at Bosscha Observatory in Lembang was also measured for comparison. Within the sensitivity limit of the measurement equipment, it is found that a location called Fatumonas in the surrounding of Mount Timau in West Timor has very low level of RFI, with a total spectrum occupancy in this measured frequency range being about 1 %, mostly found at low frequency below 20 MHz. More detailed measurements as well as a strategy for a radio quiet zone must be implemented in the near future.  相似文献   

4.
Due to its wide wavelength coverage, multi-resolution mode, and high transmission efficiency, the wide field multi-object spectrograph becomes the most common-used universal instrument in extremely large telescopes. It's still a great challenge to build the wide field multi-object spectrograph for a 30 m class telescope because of its sharply increased volume and budget. With the rapid development of astronomy and astrophysics, the innovation of astronomical technology is fundamentally required. In this paper, the research progress of different kinds of wide-field multi-object spectrographs is illustrated and reviewed, the recent status of conceptual designs and the instrument features of the wide field multi-object spectrographs of the three 30 m class telescopes in the world, especially the current effort made by the Chinese team for the wide field multi-object spectrograph of the Thirty Meter Telescope (TMT) are introduced.  相似文献   

5.
We have measured apparent fluctuations in stellar radial velocities with the ELODIE fiber-fed crossed-dispersion spectrograph and the 193-cm telescope of Observatoire de Haute-Provence. Within one given night, the fluctuations consist of two terms which may be sorted out. The first comes from imperfect scrambling of the stellar beam; the second arises from photon noise and agrees closely with our published calculations. So far, scrambler noise dominates for bright stars, but a perfect scrambler could be built by combining adatative optics and a single-mode fiber. The photon-noise results confirm that extrasolar planetary searching by the radial-velocity technique may be implemented with relatively small telescopes for a large number of stars. Consequences for the detection of astrophysical noise are discussed.  相似文献   

6.
One of the key goals of NASA’s astrophysics program is to answer the question: How did galaxies evolve into the spirals and elliptical galaxies that we see today? We describe a space mission concept called Galaxy Evolution Spectroscopic Explorer (GESE) to address this question by making a large spectroscopic survey of galaxies at a redshift, z～1 (look-back time of ～8 billion years). GESE is a 1.5-m space telescope with an ultraviolet (UV) multi-object slit spectrograph that can obtain spectra of hundreds of galaxies per exposure. The spectrograph covers the spectral range, 0.2–0.4 μm at a spectral resolving power, R～500. This observed spectral range corresponds to 0.1–0.2 μm as emitted by a galaxy at a redshift, z=1. The mission concept takes advantage of two new technological advances: (1) light-weighted, wide-field telescope mirrors, and (2) the Next-Generation MicroShutter Array (NG-MSA) to be used as a slit generator in the multi-object slit spectrograph.  相似文献   

7.
We describe the design of a suspended low- and medium-resolution spectrograph (R ≈ 300–1300) designed and made at the Special Astrophysical Observatory of the Russian Academy of Sciences for the 1.6-m AZT-33IK telescope of Sayan Observatory of the Institute of Solar-Terrestrial Physics of the Siberian Branch of the Russian Academy of Sciences. We report the results of laboratory measurements of the parameters of the instrument and tests performed on the 1-m Zeiss-1000 telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. We measured the total quantum efficiency of the “spectrograph + telescope + detector” system on AZT-33IK telescope, which at its maximum reaches 56%. Such a hight transparency of the spectrograph allows it to be used with the 1.6-m telescope to determine the types and redshifts of objects with integrated magnitudes mAB ≈ 20–21, and this result was confirmed by actual observations.  相似文献   

8.
The variability of positional and photometric parameters of the lines in the spectrum of HD 93521 is analyzed using CCD spectra taken with the PFES echelle spectrograph of the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS). To study the velocity field of the star’s atmosphere, the radial velocity variations are measured separately for the blue and red halves of the absorption profile at different levels of residual line intensity. The amplitude and phase of temporal variations of radial velocity differ for the two halves of the absorption profile. In case of strong HeI, Hβ, andHα lines the amplitude depends on intensity r. The time scales (P) of radial velocity variations and the mean halfwidths \(\overline {FW H M} \) differ for different lines and correlate fairly well with their central depths. The increase of P and decrease of \(\overline {FW H M} \) from weak to strong lines are due to the differential nature of the rotation of the star. Our analysis proofs that HD 93521 is a run-away star and this fact explains its location at a distance of about 2.0 kpc above the Galactic plane.  相似文献   

9.
On the night of August 30/31, 1975, one of the authors discovered a nova in the constellation Cygnus. Spectroscopic observations of the nova were made with a 70-cm meniscus telescope, using a 72-cm, 8°, objective prism and a diffraction spectrograph mounted at the Cassegrain focus. The radial velocity of expansion of the nova's shell turned out to be about 2000 km/sec and its mass was on the order of 10-5 M and had a tendency to increase with time; we estimated the emission energy to be 5·1044 erg and the kinetic energy of the shell to be 1045 erg, while the electron temperature in the shell is 5000 K.  相似文献   

10.
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11.
Since 1992 the solar tower telescope of Nanjing University (118°51 E, 32°03 N) as well as its multichannel solar spectrograph, originally established in 1982, have been reconstructed and a two-channel imaging spectrograph has been operated successfully. The apertures of the coelostat and the secondary mirror are both 60 cm. The spherical objective mirror, having an aperture of 43 cm and a focal length of 2170 cm, produces a solar image of 20 cm diameter. Two auxiliary telescopes using a small fraction of the coelostat's aperture were set up for guiding and H monochromatic monitoring. A multichannel spectrograph can be operated in six wavebands simultaneously. A CCD imaging spectrograph can be used for data acquisition at H and Caii K line wavebands automatically and simultaneously. The instrument consists of two CCD cameras, an image processor (SR-151), a personal computer, and a mechanical scanning device. The principal characteristics of the instruments are described. Some observational results are presented as examples.  相似文献   

12.
A new fiber‐fed spectrograph was installed at the 60 cm telescope of the Stará Lesná Observatory. The article presents tests of its performance (spectral resolution, signal‐to‐noise ratio, radial‐velocity stability) and reports observations of selected variable stars and exoplanet host stars. First test observations show that the spectrograph is an ideal tool to observe bright eclipsing and spectroscopic binaries but also symbiotic and nova‐like stars. The radial‐velocity stability (60–80 m s–1) is sufficient to study spectroscopic binaries and to detect easily the orbital motion of hot‐Jupiter extrasolar planets around bright stars. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

13.
In less than a decade, infrared array detectors have revolutionized infrared astronomy. Most of us remember using single element photometers in the early eighties, yet today, most of us are using 256×256 pixel arrays. At this meeting we have heard of plans to fabricate 1024×1024 arrays in the near infrared. From one to one million pixels in such a short period of time is amazing. The new array technology has also stimulated the development of many varieties of infrared cameras and spectrometers. At the UCLA Infrared Imaging Detector Lab we have commissioned two near infrared imaging systems (KCam and Gemini) based on 256×256 arrays and a spectrometer design study is in progress for 1024×1024 arrays. Performance of these cameras on the telescope will be reported briefly.  相似文献   

14.
We describe the future night‐time spectrograph for the GREGOR solar telescope and present its science core projects. The spectrograph provides a 3‐pixel resolution of up to R = 87 000 in 45 échelle orders covering the wavelength range 390‐900 nm with three grating settings. An iodine cell can be used for high‐precision radial velocity work in the 500‐630 nm range. The operation of the spectrograph and the telescope will be fully automated without the presence of humans during night‐time and will be based on the successful STELLA control system. Future upgrades include a second optical camera for even higher spectral resolution, a Stokes‐V polarimeter and a link to the laser‐frequency comb at the Vacuum Tower Telescope. The night‐time core projects are a study of the angular‐momentum evolution of “The Sun in Time” and a continuation of our long‐term Doppler imaging of active stars (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

15.
The construction and the optical design as well as the controlling electronic device and the spectrum recording of the new horizontal solar telescope with the spectrograph of the Astronomical Institute of Slovak Academy of Sciences are described. Also some of its adjustments and improvements are briefly mentioned.Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain.  相似文献   

16.
The suspicion of Elste (1990), that telescopic stray light together with imperfect collimation of telescope and spectrograph could be a possible explanation for the systematic differences and variations found by Neckel and Labs (1987) in many limb-darkening scans, proves to be unfounded for the following reasons: (1)The collimation was performed very precisely; (2) the telescope mirrors remained fixed in position and direction during most of the observing period; (3) stray light effects depending on hour angle were not detectable; (4) in the same collimation status, also many almost symmetric scans had been recorded; (5) the observed east-west differences in the solar intensities are partly even larger than the total amount of stray light (from telescope and sky!) observed as sky-background just outside the limb; (6) any east-west differences in the sky-background near the limb are just a few 0.01% of the disk center intensity; (7) the differences of the average intensities along eastern and western radius appear to be correlated with the east-west differences of the intensity's R.M.S.  相似文献   

17.
射电望远镜的发展和前景   总被引：1，自引：0，他引：1  
在近代科学技术发展的基础上诞生和成长起来的射电天文学已经走过了66年的历程,作为射电天文学主要探测工具的射电望远镜有了长足的进步,面临21世纪人类社会和自然科学技术包括天文学发展的挑战,射电望远镜及射电天文学将迈出新的步伐．从射电天文学和射电望远镜发展的关系、射电望远镜几个主要发展方向和目前水平、自90年代以来逐步勾画而明确起来的未来发展方向等方面阐明了射电望远镜的发展和前景,以作为我国发展新一代射电望远镜的参考．  相似文献   

18.
Because of its geographical location and (astronomically) excellent climate South Africa can make an unique contribution to international astronomical research. An assessment of recent developments in telescope technology has shown that an advanced technology telescope of 4m-class can be constructed which will out-perform most existing 4m-class telescopes. Detailed consideration is given to the construction of such a telescope for optical/infrared astronomy, the new science that this will enable and the selection of a site of sufficiently good quality to justify the erection of such a telescope. If a telescope of this nature is sited in southern Africa it would provide the premier astronomical facility in Africa for decades to come.  相似文献   

19.
We present new radial velocities of the high‐mass X‐ray binary star 4U 2206+54 based on optical spectra obtained with the Coudé spectrograph at the 2 m RCC telescope of the Rozhen National Astronomical Observatory, Bulgaria in the period November 2011–July 2013. The radial velocity curve of the He I δ6678 Å line is modeled with an orbital period Porb = 9.568 d and an eccentricity of e = 0.3. These new measurements of the radial velocity resolve the disagreements of the orbital period discussions. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

20.
The success of the International Ultraviolet Explorer (IUE) first and then of the STIS and COS spectrographs on-board the Hubble Space Telescope (HST) demonstrate the impact that observations at UV wavelengths had and are having on modern astronomy. Several discoveries in the exoplanet field have been done at UV wavelengths. Nevertheless, the amount of data collected in this band is still limited both in terms of observed targets and time spent on each of them. For the next decade, the post-HST era, the only large (2-m class) space telescope capable of UV observations will be the World Space Observatory–UltraViolet (WSO–UV). In its characteristics, the WSO–UV mission is similar to that of HST, but all observing time will be dedicated to UV astronomy. In this work, we briefly outline the major prospects of the WSO–UV mission in terms of exoplanet studies. To the limits of the data and tools currently available, here we also compare the quality of key exoplanet data obtained in the far-UV and near-UV with HST (STIS and COS) to that expected to obtain with WSO–UV.  相似文献   

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