On the nature of the FBS blue stellar objects and the completeness of the Bright Quasar Survey

The second part of the First Byurakan Survey is aimed at detecting all bright (B < 16.5) UV-excess starlike objects in a large area of the sky. By comparison with other major surveys such as the ROSA T All Sky Survey, the ROSAT WGACAT catalogue of point sources, the IRAS survey, the 6cm Green Bank, the 1.4GHz NRAO VLA, and the 92cm Westerbork Northern sky surveys and with the catalogue of mean UBVdata on stars, we estimate the number of AGNs present in the FBS survey and its completeness. We have made spectroscopic observations of nine of the most promising FBS candidates. We have found six new QSOs, bringing the total number of known QSOs in this survey to 42. By comparison with the Bright Quasar Survey, we found that the completeness of this last survey is of the order of 70% rather than 30–50% as suggested by several authors. Based party on observations collected at the Observatorie de Haute-Provence (CNRS, France). The APS databases are supported by the National Foundation, the National Aeronautics and Space Administration, and the University of Minnesota, and are available at hup:// aps.umn.edu. The Digitized Sky Survey was produced at the Space Telescope Science Institute (STScI) under U.S. Government Grant NAG W-2166. Published in Astrofizika, Vol. 42, No. 1, pp. 5–22, January–March, 1999.     

新发现7个X选 BL Lac天体和1个类星体(英文)

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．     

A Large-Scale Survey for Extremely Cold Young Stellar Objects in the Galaxy

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　　ＳｉｎｃｅｔｈｅＩＲＡＳｄｅｔｅｃｔｉｏｎ ,ｓｅｖｅｒａｌｆｏｌｌｏｗ -ｕｐｓｕｒｖｅｙｓａｎｄｃｒｏｓｓｉｄｅｎｔｉｆｉｃａｔｉｏｎｓｈａｖｅｂｅｅｎｍａｄｅａｃｃｏｒｄｉｎｇｔｏｄｉｆｆｅｒｅｎｔｃｒｉｔｅｒｉａ.Ａｔｙｐｉｃａｌｓａｍｐｌｉｎｇｍｅｔｈｏｄｉｎｔｈｅｐｒｅｖｉｏｕｓｓｕｒｖｅｙｓｉｓｆｌｕｘ -ｌｉｍｉｔｅｄ (ｅ.ｇ .,Ｓｎｅｌｌ,Ｄｉｃｋｍａｎ ,＆Ｈｕａｎｇ 1 988;ＭｃＣｕｔｃｈｅｏｎｅｔａｌ.1 991 ) .Ｓｎｅｌｌ,Ｄｉｃｋｍａｎ ,＆Ｈｕａｎｇ ( 1 98…     

年青星体附近双极喷流及其块状结构的物理机制

本文用磁拉瓦尔管机制解释了双极喷流的形成。这样,喷流内部的热压力被外部纵向磁场的磁压所平衡。本文研究了这一平衡态基础上的Kelvin-Helmholtz不稳定性,得出了共振模式的分析解。这一族解可解释喷流块状结构的许多观测特点,如块状结构的间距。高本动速度及喷流膨胀段的光学不可见性等等。     

年轻星体的近红外观测与研究

本文对36颗不同质量、不同演化阶段的年轻星体进行了J，H，K波段测光，并结合其它光学、近红外、IRAS、亚毫米、毫米波段的观测结果，计算了它们的红外色指数、能谱分布指数、红外光度等参量，得到近红外和远红外双色图，比较了不同类别源的参量分布．最后，在前人工作的基础上，改进了低质量主序前星的辐射模型，对一些源进行了计算并分析其星周状况．     

Polarimetric observations of blue FBS stellar objects. II

Translated fromAstrofizika, Vol. 36, No. 2 pp. 203–209, April–June 1993.     

The Multi-Wavelength Quasar Survey IV. Quasars in the Leo Cluster

We aim to providea quasar sample that is more complete than any previous surveys by using a combined selection technique to reduce the selection effects. Here we present the observational results for the X-ray candidates in the field of the Leo Cluster. We found 33 X-ray AGNs in this field of which 10 are new discoveries. The X-ray data and optical spectra of these AGNs are given. We also study the near-IR properties of the X-ray-selected AGNs by using the data from 2MASS. Most of the AGNs in our sample span the color range 0.0 < B-J < 2.5, 1.0 < J-Ks < 2.0 and 0.5 < H-Ks < 1.2.     

Search for New Interesting Objects in the Second Part of the FBS

We present the results of a study of the FBS blue stellar objects with the goal of discovering new interesting objects. Forty-seven FBS objects have been observed with the Byurakan Observatory 2.6m telescope in 1987-1991 and scanned with the MAMA scanning machine at Observatoire de Paris in 1997-1999. 5 QSOs/Sy1s, 4 emission-line stars, five white dwarfs, and a number of continuous spectra objects (possible BL Lacs and DC white dwarfs) have been revealed.     

On the Real Number of Objects in the Tautenburg Catalogues of Blue Objects Suspected as Quasistellar (QSO)

The results of the U, B, V photometries of W. BRONKALLA and N. RICHTER near the north galactic pole are discussed. In these photometries which have been carried out on the same Tautenburg Schmidt plates the share of blue objects suspected as quasistellar (QSO) has been determined by total photometry of all starlike objects in selected partly overlapping test fields. The results of both photometries agree very well. The position of the blue objects of the Tautenburg catalogues and BRONKALLA's photometry in the two-colour diagram is compared with the two-colour diagram of QSO's published by C. BARBIERI and M. CAPPACIOLI . In both cases 65 per cent of the objects are placed on the right-hand side and 35 per cent on the left-hand side (region of white dwarfs) of the black-body line. Therefore, it is no longer admissible to qualify in a photometric statistics of blue objects all those objects as white dwarfs which are situated on the left-hand side of the black-body line in the two-colour plot. This result is confirmed by the discussion of the number-magnitude relation of these objects. Clustering of blue objects and their connection with clusters of galaxies are discussed. Using results from A. SANDAGE and E. M. BURBIDGE and our own results one can conclude that more than 60 per cent of Tautenburg blue objects must be QSO's. For further spectroscopic and proper motion investigations it is proposed to prefer the objects placed on the left-hand side of the black-body line in order to obtain the real share of white dwarfs in this group of objects suspected to be quasistellar.     

蓝致密星系谱的星族合成

利用星团谱样本的星族合成方法,分析了四个蓝致密星系（ＢｌｕｅＣｏｍｐａｃｔＧａｌａｘｉｅｓ,ＢＣＧ）的光学谱．给出了在各个ＢＣＧ中,年龄和金属丰度不同的星族对星系５８７ｎｍ处连续谱流量贡献的比率,同时还给出ＢＣＧ内部恒星演化的历史和星系内部的红化值．通过对星系内部星族及光谱的分析,解决了ＢＣＧ研究中存在的这类星系年龄和其内部光学不可见物质等问题．结果表明ＢＣＧ是年老星系,其内部恒星形成过程为长时间的宁静相上叠加有短暂且剧烈恒星形成的爆发,其内部存在光学不可见物质,且至少有一部分为年老的球状星团;根据由光学连续谱和发射线计算星系的内红化值的不同,得出ＢＣＧ星系内部尘埃对连续谱和发射线的产生区遮挡程度不同．     

On the Use of Meteor Camera Systems in the Detection of Kuiper Belt Objects Through Serendipitous Stellar Occultations

The direct detection of Kuiper Belt Objects (KBOs) by telescopic imaging is not currently practical for objects much less than 100 km in diameter. However, indirect methods such as serendipitous stellar occultations might still be employed to detect these bodies. The method of serendipitous stellar occultations has been previously used with some success in detecting KBOs—Roques et al. (Astron J 132(2):819–822, 2006) detected three Trans-Neptunian objects; Schlichting et al. (Nature 462(7275):895–897, 2009) and Schlichting et al. (Astrophys J 761:150, 2012) each detected a single object in archival Hubble Space Telescope data. However, previous assessments of KBO occultation detection rates have been calculated only for telescopes—we extend this method to video camera systems, and we apply this derivation to the automated meteor camera systems currently in use at the University of Western Ontario. We find that in a typical scenario we can expect one occultation per month. However recent studies such as those of Shankman et al. (Astrophys. J. Lett. 764. doi:10.1088/2041-8205/764/1/L2, 2013) and Gladman et al. (AAS/Division for Planetary Sciences Meeting Abstracts, 2012) which indicate that the population of small KBOs may be smaller than has been assumed in the past may result in a sharp reduction of these rates. Nonetheless, a survey for KBO occultations using existing meteor camera systems may provide valuable information about the number density of KBOs.     

The Tails of Externally Illuminated Young Stellar Objects in the Orion Nebula

Recent observations of externally illuminated young stellar objects in the Orion Nebula show that they have a variety of morphologies. In particular, long thin tails which terminate in points have been observed. Mechanisms will be considered here to understand the formation and properties of these tails.     

Spectroscopic investigations of objects of the Second Byurakan Survey. Stellar objects. IV

Byurakan Astrophysical Observatory; Special Astrophysical Observatory, USSR Academy of Sciences. Translated from Astrofizika, Vol. 34, No. 1, pp. 5–12, January–February, 1991.     

Counts of Faint Blue Objects and the Anomalous Red Shift

The hypothesis that the spectra of young objects contain an anomalous red shift which decreases and disappears as they evolve is considered. The possibility of detecting features of this anomalous red shift in the spectra of postquasar objects is considered under the assumption that a large fraction of the quasars are local objects ejected from galactic nuclei. It is argued that the anomalous red shift has a significant effect on the form of the observed luminosity function for the local population of galaxies, depleting it at faint magnitudes. This approach is used to examine the problem of excess blue galaxies.     

Jets from Young Stellar Objects: Current Constraints and Challenges for the Future

I outline future directions of research that seem promising and necessary to identify the ejection process in YSO jets, including observational tests of ejection models, and challenging theoretical and observational issues.     

Spectroscopic investigation of objects of the Second Byurakan Survey. Stellar objects. V

Byurakan Astrophysical Observatory; Special Astrophysical Observatory. Translated from Astrofizika, Vol. 34, No. 3, pp. 315–325, May–June, 1991.     

The Blue Stragglers and the Integrated Spectral Energy Distribution of Single Stellar Populations

1　ＩｎｔｒｏｄｕｃｔｉｏｎＳｉｎｇｌｅＳｔｅｌｌａｒＰｏｐｕｌａｔｉｏｎｓ (ＳＳＰｓ)ａｒｅｔｈｅｂａｓｉｃｂｕｉｌｄｉｎｇｂｌｏｃｋｓｏｆｓｙｎｔｈｅｔｉｃｓｐｅｃｔｒａｏｆｇａｌａｘｉｅｓ(Ｂｒｅｓｓａｎｅｔａｌ1 994) .Ｉｎｔｈｅｆｒａｍｅｗｏｒｋｏｆｔｈｅｅｖｏｌｕｔｉｏｎａｒｙｐｏｐｕｌａｔｉｏｎｓｙｎｔｈｅｓｉｓｓｔｕｄｙ ,ＳＳＰｓａｒｅｍｏｄｅｌｌｅｄｗｉｔｈｐｒｏｐｅｒｓｔｅｌｌａｒｅｖｏｌｕｔｉｏｎａｒｙｔｒａｃｋｓｏｆｄｉｆｆｅｒｅｎｔｍａｓｓｅｓａｎｄｉｎｉｔｉａｌｃｈｅｍｉ…