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1.
We present our observations of the galaxy UGS 5600 with a long-slit spectrograph (UAGS) and a multipupil field spectrograph (MPFS) attached to the 6-m Special Astrophysical Observatory telescope. Radial-velocity fields of the stellar and gaseous components were constructed for the central region and inner ring of the galaxy. We proved the existence of two nearly orthogonal kinematic subsystems and conclude that UGC 5600 is a galaxy with an inner polar ring. In the circumnuclear region, we detected noncircular stellar motions and suspected the existence of a minibar. The emission lines are shown to originate in H II regions. We estimated the metallicity from the intensity ratio of the [N II]λ6583 and Hα lines to be nearly solar, which rules out the possibility that the polar ring was produced by the accretion of gas from a dwarf companion. 相似文献
2.
The potential of an algorithm of semiempirical modeling of stellar spectra recorded via an iodine absorption cell is analyzed. This algorithm, when used with the NES quartz echelle spectrograph of the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences, is shown to be able to achieve a Doppler shift measurement accuracy of 20 m/s with an internal accuracy of 2 m/s. 相似文献
3.
G. Catanzaro 《Astrophysics and Space Science》1997,257(1):161-170
Before reaching our telescopes, stellar radiation passes through Earth's atmosphere. This interaction causes the formation of a number of telluric lines in registered stellar spectra. In this paper an atlas of atmospheric lines is reported. Observations have been carried out at the 91 cm cassegrain telescope of the M. G. Fracastoro observing station of the Catania Astrophysical Observatory equipped with a Czerney-Turner echelle spectrograph. The spectral region examined is between 6800 Å and 7800 Å. The possibility of using this atlas either to recognize telluric lines or as a wavelength calibration source is also discussed. 相似文献
4.
I. V. Chilingarian O. K. Sil’chenko V. L. Afanasiev Ph. Prugniel 《Astronomy Letters》2007,33(5):292-298
We report the discovery of young embedded structures in three diffuse elliptical galaxies (dE) in the Virgo cluster: IC 783,
IC 3468, and IC 3509. We performed 3D spectroscopic observations of these galaxies with the MPFS spectrograph at the 6-m Special
Astrophysical Observatory telescope and obtained spatially resolved distributions of kinematic and stellar population parameters
by fitting high-resolution PEGASE. HR synthetic single stellar populations (SSP) in pixel space. In all three galaxies, the
luminosity-weighted age of the nuclei (∼4 Gyr) is considerably younger than that of the population in the outer regions of
the galaxies. We discuss two possibilities for the formation of such structures—a dissipative merger event and a different
ram pressure stripping efficiency during two consecutive crossings of the Virgo cluster centre.
The article was translated by the authors. 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.
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
7.
A. V. Moiseev 《Astrophysical Bulletin》2008,63(1):70-82
We analyze factors that affect the accuracy of stellar line-of-sight velocities measured from the spectra obtained with the SCORPIO instrument attached to the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. We show that nonuniform illumination of the spectrograph slit combined with the effect of differential atmospheric refractionmay result in substantial systematic errors in the inferred line-of-sight velocities, and formulate recommendations concerning the methodology of observations, which allow the errors of line-of-sight velocity measurements to be minimized. 相似文献
8.
E. Caffau A. Mott M. Steffen P. Bonifacio K. G. Strassmeier A. Gallagher R. Faraggiana L. Sbordone 《Astronomische Nachrichten》2015,336(10):968-980
We present a detailed analysis of seven young stars observed with the spectrograph SOPHIE at the Observatoire de Haute‐Provence for which the chemical composition was incomplete or absent in the literature. For five stars, we derived the stellar parameters and chemical compositions using our automatic pipeline optimized for F, G, and K stars, while for the other two stars with high rotational velocity, we derived the stellar parameters by using other information (parallax), and performed a line‐by‐line analysis. Chromospheric emission‐line fluxes from Caii are obtained for all targets. The stellar parameters we derive are generally in good agreement with what is available in the literature. We provide a chemical analysis of two of the stars for the first time. The star HIP 80124 shows a strong Li feature at 670.8 nm implying a high lithium abundance. Its chemical pattern is not consistent with it being a solar sibling, as has been suggested. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
9.
A new type of optical fiber T.V. adaptor-link device is developed to bring a star image at the focus of a Schmidt telescope to the slit of a spectrograph located at the observing floor, as well as part of the field, to a T.V. monitor for acquisition and guiding purposes. The device is constructed by 60 000 thin glass fibers (18 micron in diameter and 1.2 m in length) used as the adaptor, and a single long (20 m) thicker (25 micron core diameter) fused silica fiber used as the link between the telescope and the spectrograph. The 60 000 thin fibers are arranged in a 4 by 5 mm rectangular array with the link built in the center of the field. With the adaptor-link the astronomer can easily acquire the star on the T.V. monitor, transfer the star image through the link to the slit of the spectrograph and guide the star during observation. 相似文献
10.
We have investigated the central regions of the galaxies in the NGC 3169/NGC 3166/NGC 3156 group with the multipupil fiber spectrograph of the 6-m telescope; the first (central) galaxy in the group is a spiral (Sa) one and the other two galaxies are lenticular ones. The group is known to have an extended HI cloud with a size of more than 100 kpc that is associated in its position, orientation, and rotation with the central galaxy NGC 3169. The mean age of the stellar populations in the centers of all three galaxies has been found to be approximately the same, ～1 Gyr. Since the galaxies are early-type ones and since NGC 3166 and NGC 3156 show no global star formation, we are dealing here with a synchronous star formation burst in the centers of all three galaxies. 相似文献
11.
12.
G. Hildebrandt G. Scholz J. Rendtel M. Woche H. Lehmann 《Astronomische Nachrichten》1997,318(5):291-304
We describe the TRAnsportable Flbre COupled échelle Spectrograph (TRAFICOS) equipped with a Zeeman analyzer and manufactured mainly for the observation of stellar magnetic fields. The spectrograph, designed at the Astrophysikalisches Institut Potsdam and constructed at the Thüringer Landessternwarte Tautenburg, is laid out in a quasi-Littrow configuration. The part attached to the Nasmyth focus of the 2 m telescope contains the telescope adapter for the fibre input and output of the star and calibration light, the cases for the flatfield and the wavelength calibration, and the Zeeman analyzer. The optical scheme and the reduction software are mentioned in some details and the first results of the determination of the magnetic field and radial velocity of several stars are given showing the performance of the device in comparison with existing data. 相似文献
13.
Yong Zhao Zhou Fan Juan-Juan Ren Liang Ge Xiao-Ming Zhang Hong-Bin Li Hui-Juan Wang Jian-Feng Wang Peng Qiu Xiao-Jun Jiang 《天文和天体物理学研究(英文版)》2018,(9)
The Beijing Faint Object Spectrograph and Camera(BFOSC) is one of the most important instruments operating in conjunction with the 2.16-m telescope at Xinglong Observatory. Every year there are~20 SCI-papers published based on observational data acquired with this telescope. In this work,we have systemically measured the total efficiency of the BFOSC that operates as part of the 2.16-m reflector, based on observations of two ESO flux standard stars. We have obtained the total efficiencies of the BFOSC instrument of different grisms with various slit widths in almost all ranges, and analyzed factors which effect the efficiency of this telescope and spectrograph. For astronomical observers, the result will be useful for them to select a suitable slit width, depending on their scientific goals and weather conditions during observations. For technicians, the result will help them to systemically identify the real efficiency of the telescope and spectrograph, and to further improve the total efficiency and observing capacity of the telescope technically. 相似文献
14.
B. E. Zhilyaev A. V. Sergeev M. V. Andreev V. G. Godunova V. N. Reshetnik V. K. Taradii 《Kinematics and Physics of Celestial Bodies》2013,29(3):120-130
A slitless UBVR spectrograph has been built for use on small telescopes. Test observations on the Zeiss-600 telescope at the Terskol peak demonstrated that the spectrograph is an efficient instrument for studying high-speed processes in variable stars with a high temporal resolution. The spectrograph resolving power R ≈ 100 in the vicinity of λ = 480 nm and the error in the determination of the wavelength is approximately 3 nm. The spectrograph provides a moderate signal-to-noise ratio for stars up to 16 m . It permits one to measure equivalent widths of unblended lines down to 0.1 nm. The developed special software based on the theory of quantum statistics makes it possible to detect relative variations in the spectrum of approximately 10?5–10?6 of the bolometric flux of the star. Observations with the spectrograph made it possible to detect variations of emissions in Balmer lines and Ca II H, K lines in the EV Lac flare star in the subsecond range. The spectroscopic monitoring permits one to study stellar flares with small amplitude, to carry out a comprehensive colorimetric analysis of flare plasma, and to determine temperatures and sizes of flares in the light intensity maximum. Observations of the transit of the HAT-P-1 B exoplanet demonstrate that the chromospheric activity power of the parent star does not vary during the transit. The slitless spectrograph with a low resolving capacity opens new prospects in studying active processes occurring on stars’ surfaces. 相似文献
15.
G. A. Chountonov 《Astrophysical Bulletin》2010,65(1):95-100
We have developed and manufactured a fiber-optic magnetometer for the prime focus of the 6-m BTA telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences based on a suspended echelle spectrograph. The magnetometer is designed to improve the spectrum stability and eliminate the effect of instrumental polarization of the diagonal mirror on the results of magnetic field measurements. The magnetometer is to be used for measurements of stellar magnetic fields in stars and to study their chemical composition. The instrument operates in the 5000–6800 Å wavelength interval with mean reciprocal dispersion of 0.15 Å/pixel. According to the estimates for 9 m .5 stars, the standard error of magnetic field measurements based on 400 spectral lines would be 100 G for a half-hour exposure. 相似文献
16.
C. J. Hansen H.‐G. Ludwig W. Seifert A. Koch W. Xu E. Caffau N. Christlieb A. J. Korn K. Lind L. Sbordone G. Ruchti S. Feltzing R. S. de Jong S. Barden O. Schnurr 《Astronomische Nachrichten》2015,336(7):665-676
From stellar spectra, a variety of physical properties of stars can be derived. In particular, the chemical composition of stellar atmospheres can be inferred from absorption line analyses. These provide key information on large scales, such as the formation of our Galaxy, down to the small‐scale nucleosynthesis processes that take place in stars and supernovae. By extending the observed wavelength range toward bluer wavelengths, we optimize such studies to also include critical absorption lines in metal‐poor stars, and allow for studies of heavy elements (Z ≥ 38) whose formation processes remain poorly constrained. In this context, spectrographs optimized for observing blue wavelength ranges are essential, since many absorption lines at redder wavelengths are too weak to be detected in metal‐poor stars. This means that some elements cannot be studied in the visual‐redder regions, and important scientific tracers and science cases are lost. The present era of large public surveys will target millions of stars. It is therefore important that the next generation of spectrographs are designed such that they cover a wide wavelength range and can observe a large number of stars simultaneously. Only then, we can gain the full information from stellar spectra, from both metal‐poor to metal‐rich ones, that will allow us to understand the aforementioned formation scenarios in greater detail. Here we describe the requirements driving the design of the forthcoming survey instrument 4MOST, a multi‐object spectrograph commissioned for the ESO VISTA 4 m‐telescope. While 4MOST is also intended for studies of active galactic nuclei, baryonic acoustic oscillations, weak lensing, cosmological constants, supernovae and other transients, we focus here on high‐density, wide‐area survey of stars and the science that can be achieved with high‐resolution stellar spectroscopy. Scientific and technical requirements that governed the design are described along with a thorough line blending analysis. For the high‐resolution spectrograph, we find that a sampling of ≥2.5 (pixels per resolving element), spectral resolution of 18000 or higher, and a wavelength range covering 393–436 nm, is the most well‐balanced solution for the instrument. A spectrograph with these characteristics will enable accurate abundance analysis (±0.1 dex) in the blue and allow us to confront the outlined scientific questions. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
17.
N. N. Stepanian G. A. Sunitsa V. M. Malashchuk 《Bulletin of the Crimean Astrophysical Observatory》2014,110(1):149-160
Questions of the mounting and adjustment of a tower solar telescope are considered through the example of the TST-2 telescope of the Crimean Astrophysical Observatory Scientific Research Institute. The authors describe the optical circuits of the telescope and spectrograph and list the basic requirements for the mutual arrangement of individual components of the telescope. Simple methods for adjusting elements of the telescope and spectrograph are described. 相似文献
18.
19.
A digital television complex, equipped with an original slitless spectrograph with transpaarent diffraction gratings, and operating on the 0.5-meter telescope of the Crimean Astrophysical Observatory, was used for spectrophotometric observations of the nuclei of Seyfert galaxies. The absolute energy distributions in the spectra of the nuclei of the Seyfert galaxies NGC 4501, NGC 7469, and NGC 1275 in the wavelength range 4000–7000 Å were obtained. Synthetic stellar magnitudes in the V band were calculated. The apparatus can be used to investigate the spectral variability of emission from the nuclei of Seyfert galaxies on a time scale of tens of minutes or more.Translated from Astrofizika, Vol. 39, No. 1, pp. 101–110, January–March, 1996. 相似文献
20.
Hsin Heng Wu 《Astrophysics and Space Science》1986,118(1-2):415-418
A Reducing Camera designed by Meinel has been constructed and tested on the 61 cm NCU Cassegrain telescope. The basic principle of RC is to reduce the reflector'sf/13.5 to the equivalentf/2.7 such that the Cassegrain focus image can be reduced on a 35 mm film with almost no loss in sky coverage and in resolution but the exposure time is reduced by a factor of 25. The camera is able to obtain stellar spectra. With a grism and a standard lens the dispersion is 450 Å mm–1, which is comparable to that required for the MK classification. RC constructure and testing results are reported. The method of a wide field spectrograph and that of narrow band differential photography of RC are also discussed.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献