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1.
利用ROSAT-VLA方法筛选,从ROSATX射线源中选出了19个新BLLac天体和类星体的候选体.在1994年至1996年1月期间,利用北京天文台2.16m望远镜对其中16个进行光谱证认,发现了7个新的X选BLLac天体及一个类星体,类星体的红移值为:z=0.331±0.0015.  相似文献   

2.
新发现的4个X选类星体和2个赛弗特星系   总被引:2,自引:1,他引:1  
1997-1998年期间,使用2.16m望远镜对ROSAT X射线源进行光学证认,证认出4个ROSAT X射线源是新发现的类星体,2个ROSAT X射线源是新发现的赛弗特星系。  相似文献   

3.
1995年5月,使用2.16m望远镜对ROSAT X射线源进行光学证认期间,发现8个ROSAT X射线源和5G射电源的光学对应体是以前未发现的类星体,其红移范围从0.333至1.091。本文给出了这些类星体的多波段特性。  相似文献   

4.
1995年5月,使用2.16m望远镜对ROSATX射线源进行光学证认期间,发现8个ROSATX射线源和5G射电源的光学对应体是以前未发现的类星体,其红移范围从0.333至1.091。本文给出了这些类星体的多波段特性。  相似文献   

5.
为了研究ROSATX射线选亮近类星体巡天的选择判据 ,从 1 995年 4月至 1 996年 1 0月期间 ,利用北京天文台 2 .1 6米望远镜进行了试验观测 ,发现了 73个类星体、2 7个赛弗特星系、1个BLLac候选体、1个白矮星和 1个激变变星  相似文献   

6.
利用ROSAT-VLA方法筛选,从ROSATX射线源中选出了19个新BLLac天体和类星体的候选体,在1994年至1996年1月期间,利用北京天台2.16m望远镜对其中16个进行光谱证认,发现了7个新的X选BLLac天体及一个类星体,类星体的红外移值为:Z=0.331±0.0015。  相似文献   

7.
1990年6月发射的ROSAT卫星完成了全天的X射线巡天观测,得到了包括18811个X射线源的ROSAT全天巡天亮源表(RASS-BSC)。通过对ROSAT亮X射线源不学对应体的证认,我们已经发现了7个激变变星,给出了这7个激变变星的低色散光谱,并根据它们的光谱特征及其它性质进行了讨论。  相似文献   

8.
利用ROSATVLA方法筛选,从ROSATX射线源中选出了一批新的BLLac天体和类星体的候选体.1996年12月8日至17日,利用北京天文台2.16m望远镜和OMR摄谱仪,对这批新候选体进行了光谱认证.经SUN工作站处理,又发现了5个新的X选类星体和1个Seyfert星系.此外,在扩大光谱波长覆盖范围到8500的条件下,重新观测了作者去年所发现的BLLac天体,结果发现2318+304在7259处有一很强的Hα6563+[NI]6548,6583发射线.因此,可以确定2318+304是一个类星体,而不是一个BLLac天体.  相似文献   

9.
低质量恒星形成区Taurus-Auriga外围区ROSAT定点观测选弱发射线T Tauri星候选体(WTTS)的光谱证认新发现4个WTTS。本给出了目标源的USNO R星等、USNO坐标(J2000)、分类光谱型、Hα发射/吸收线和富LiX射线源,包括新发现WTTS的LiI吸收线强度等参量以及WTTS的特征光谱。并利用Hipparcos星表对部分目标源进行了视差和自行的研究。另外,本第一次给出  相似文献   

10.
为了深入研究密云射电源表分类样本的性质,作为系列工作的第一部分,选出了一个232~4850MHz平谱源样本.1998年5月29至31日,利用北京天文台2.16米望远镜和OMR摄谱仪,对其中18个目标进行了观测及光谱认证.结果共证认出15个AGN,其中3个信噪比不小于8的BLLac天体和5个类星体(最大红移为2.519±0.003)是新发现的.  相似文献   

11.
12.
In the course of our search for the optical identifications of ROSAT X-ray sources, we have found a highly variable object with a very unusual behavior on long time scales, rare color indices, and a high X-ray-to-optical flux ratio. We present the archival light curve from the Catalina Sky Survey, optical spectroscopy from RTT150, and time-resolved photometry from the Astrotel-Caucasus telescope. The object appears to be a magnetic cataclysmic variable (a polar) with an orbital period P = 3.20 h.  相似文献   

13.
主动光学─新一代大望远镜的关键技术   总被引:1,自引:0,他引:1  
对主动光学技术在现代天文光学望远镜中的作用和工作原理作了较全面的介绍和评论。结合作者近十年的工作对薄镜面主动光学技术和拼接镜面主动光学技术的各个关键部分,如波前检测、波前拟合、校正力的确定、共焦和共面的检测作了较详细且深入的讨论和评述.也介绍了我国目前正在研制的同时采用薄镜面主动光学和拼接镜面主动光学技术的大天区面积多目标光纤光谱望远镜的主动光学系统。  相似文献   

14.
We present the results of our optical identification of two X-ray sources from the RXTE and INTEGRAL all-sky surveys: XSS J00564+4548 and IGR J00234+6141. Using optical observations with the 1.5-m Russian-Turkish Telescope (RTT150) and publicly accessible X-ray data from the SWIFT Orbital Observatory, we show that these sources are most likely intermediate polars, i.e., binary systems with accreting white dwarfs that possess a moderately strong magnetic field (≲10 MG). We have found periodic optical oscillations with periods of ≈480 and ≈570 s. These periods most likely correspond to the rotation periods of the white dwarfs in these systems. Further optical RTT150 observations of these systems will allow their parameters to be studied in more detail. Published in Russian in Pis’ma v Astronomicheskiĭ Zhurnal, 2006, Vol. 32, No. 9, pp. 655–661. The article was translated by the authors.  相似文献   

15.
We present new results of our kinematic study of the supernova remnant S8 in the galaxy IC 1613. Based on our observations at the 6-m Special Astrophysical Observatory telescope with the two-dimensional MPFS spectrograph and the SCORPIO focal reducer in the mode of a scanning Fabry-Perot interferometer, we have determined the expansion velocity of the bright optical nebula. Analysis of the 21-cm VLA radio observations for the galaxy confirms our previously suggested model for a supernova explosion in a cavity surrounded by a dense HI shell and a collision of S8 with the shell wall.  相似文献   

16.
This paper covers the main aspects of three new optical telescopes: a 1.26 m aperture one for use in the infrared, a 1.56 m aperture one for astrometry, and a 2.16 m reflector for general astrophysical work. It also briefly mentions the 13.7 m telescope designed for the mm wavelength band, the first VLBI in China and the meter wavelength aperture synthesis telescope. All these telescopes, optical and radio, are now being built in China.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984.  相似文献   

17.
We present here the results of our high resolution echelle spectroscopic observations of six recently identified spectroscopic binary systems with late-type stellar components (HD 82159 (BD + 11 2052 A); HIP 63322 (BD + 39 2587); HD 160934 (RE J1738 + 611); HD 89959 (BD + 41 2078); HD 143705 (BD + 29 2752); HD 138157 (OX Ser)). The orbital solution has been obtained using precise radial velocities determined by cross-correlation with radial velocity standard stars as well as previous values reported by other authors. These multiwavelength optical observations allow us to study the chromosphere of these active binary systems using the information provided by several optical spectroscopic features (from Ca II H &; K to Ca II IRT lines) that are formed at different heights in the chromosphere. The chromospheric contribution in these lines has been determined using the spectral subtraction technique. In addition, we have determined rotational velocities (vsin i), lithium (Li I λ 6707.8 Å) abundance, and kinematic properties (membership in representative young disk stellar kinematic groups).  相似文献   

18.
We present new observations of seven late-type stars previously discovered in the First Byurakan Survey (FBS). These observations prove that they belong to the family of carbon (C) stars. Seventy-nine similar FBS C stars were previously known. The seven objects under analysis were presented in the FBS lists as M or C star candidates. Among the seven objects, six objects are confirmed by low-resolution spectra of the Hamburg Quasar Objective-Prism Survey. We also present for five of them moderate-resolution spectra obtained at optical wavelengths with a spectrograph equipped with a CCD detector. Three objects can be classified as N-type C stars. One object is an early CH-type C star. Most likely, the star FBS 1339+117 belongs to the group of carbon dwarfs. We estimate distances of these seven new C stars either by using their red-band magnitudes, or by using their near-infrared 2MASS J-KS color and KS-band magnitudes. Published in Astrofizika, Vol. 51, No. 2, pp. 255–265 (May 2008).  相似文献   

19.
We present the results of our optical identifications of a set of X-ray sources from the INTEGRAL and SWIFT all-sky surveys. The optical data have been obtained with the 1.5-m Russian-Turkish Telescope (RTT-150). Nine X-ray sources have been identified with active galactic nuclei (AGNs). Two of them are located in the nearby spiral galaxies MCG-01-05-047 and NGC 973 seen almost edge-on. One source, IGR J16562-3301, is probably a BL Lac object (blazar). The remaining AGNs are observed as the starlike nuclei of spiral galaxies whose spectra exhibit broad emission lines. The relation between the hard X-ray (17–60 keV) luminosity and the [O III] 5007 line luminosity, log L x/L [O III] ≈ 2.1, holds good for most of the AGNs detected in hard X rays. However, the luminosities of some AGNs deviate from this relation. The fraction of such objects can reach ~20%. In particular, the [O III] line flux is lower for two nearby edge-on spiral galaxies. This can be explained by the effect of absorption in the galactic disks.  相似文献   

20.
We propose a next generation space instrument: the Fresnel imager, a large aperture and lightweight focusing device for UV astrophysics. This paper presents the laboratory setup used to validate the Fresnel imager at UV at wavelengths around 260 nm, and the results obtained. The validation of this optical concept in the visible domain has been previously published, with the first results on sky objects. In this paper we present new optical tests in the UV, of diffractive focusing and chromatic correction at wavelengths around 260 nm. The results show images free from chromatic aberration, thanks to a chromatic corrector scheme similar to the one used in the visible. To complete these tests and reach real astrophysical UV sources, we propose a short space mission featuring a Fresnel imager prototype placed on the international space station: during the mission this small aperture instrument would be aimed at UV sources such as bright stars and solar system objects, to assess at relatively low cost the limits in contrast and resolution of diffractive focusing in space conditions, on real UV astrophysical objects. At wavelengths from 100 to 300 nm, covering Lyman-α, we expect some scientific return from this mission, but the main goal is to increase the TRL, improving the chances of success for a later proposal featuring a full fledged Fresnel imager 10 meters in aperture or more, that would explore new domains of UV astrophysics at very high angular resolution and very high contrast.  相似文献   

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