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The characteristic periodicity analysis of the radio flux variability of quasar PKS 1510-089

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Science China(Physics,Mechanics & Astronomy) 2009年第9期52卷 1442-1448页

作者： ZHANG HaoJing ZHAO Gang ZHANG Xiong DONG FuTong XIE ZhaoHua YI TingFeng ZHENG YongGang BAO YuYing National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Graduate Univensity of Chinese Academy of Sciences Beijing 100049China Department of Physics Yunnan Normal UniversityKunming 650092China Department of Physics Yunnan UniversityKunming 650091China Department of Physics Yuxi Normal UniversityYuxi 653100China

A wavelet analysis method is introduced to study the possible periods of PKS 1510-089 in radio bands. By compiling the radio light curve of PKS 1510-089 at frequencies of 22 and 37 GHz from 1990 to 2005, and using the wavelet analysis method, the evidence of quasi-periodic activity in PKS 1510-089 was obtained. The results indicate that: (1) There are two stable outburst periods of T1=(1.80±0.06) yr and T2= (0.90±0.07) yr presenting in the isoplethal map of PKS 1510-089 at the radio band 37 GHz; (2) there is an outburst period of T1=(1.80±0.06) yr presenting at the radio band 22 GHz; (3) by the continuum of the isograms map, we find the primary period of PKS 1510-089 is T1=(1.80±0.06) yr, and the period of T2= (0.90±0.07) yr may be the half period. The above results are consistent with the reports of Xie et al. (2004, 2005, 2008), Wu et al. (2005) and Liu & Fan (2007), using the other methods. We can expect that the next burst will be in January 2011.

关键词： quasar object individual (PKS 1510-089) radio band’s periodicity analysis wavelet analysis radio flux black hole mass

quasar:一种生物序列数据库的搜索算法

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现代图书情报技术 2006年第4期 74-76页

作者：喻钧胡志毅王建国西安工业学院计算机科学与工程学院西安710032 总后建筑工程研究所西安710032

介绍一种生物序列数据库的搜索算法———quasar,即采用索引的后缀数组,通过筛选q-gram进行局部比对的方式来搜索查询序列在数据库中的近似匹配,并运用窗口推移和分块查找的方法来加快搜索和节省搜索空间。同时,将quasar和最流行的BLAS... 详细信息

介绍一种生物序列数据库的搜索算法———quasar,即采用索引的后缀数组,通过筛选q-gram进行局部比对的方式来搜索查询序列在数据库中的近似匹配,并运用窗口推移和分块查找的方法来加快搜索和节省搜索空间。同时,将quasar和最流行的BLAST搜索工具进行简单比较。

关键词：生物序列数据库 quasar 数据搜索

Alignment of quasar Polarizations on Large Scales Explained by Warped Cosmic Strings. PART II: The Second Order Contribution

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Journal of Modern Physics 2017年第2期8卷 163-180页

作者： Reinoud Jan Slagter Asfyon Bussum The Netherlands Amsterdam University Amsterdam The Netherlands

We find an azimuthal-angle dependent approximate wave like solution to second order on a warped five-dimensional manifold with a self-gravitating U(1) scalar gauge field (cosmic string) on the brane using the multiple-scale method. The spectrum of the several orders of approximation show maxima of the energy distribution dependent on the azimuthal-angle and the winding numbers n of the subsequent orders of scalar field. This breakup of the quantized flux quanta does not lead to instability of the asymptotic wavelike solution, due to the suppression of the n-dependency in the energy mo-mentum tensor components by the warp factor. This effect is triggered by the contribution of the five dimensional Weyl tensor on the brane. This con-tribution can be understood as dark energy and can trigger the self-acceleration of the universe without the need of a cosmological constant. There is a striking relation between the symmetry breaking of the Higgs field described by the winding number and the SO(2) breaking of the axially symmetric configuration into a discrete subgroup of rotations about 180°. The discrete sequence of non-axially symmetric deviations, cancelled by the emission of gravitational waves in order to restore the SO(2) symmetry, triggers the pressure Tzz for discrete values of the azimuthal-angle. There can be a possible relation between the recently discovered angle-preferences of polarization axes of quasars on large scales and our theoretical predicted angle-dependency and can be an evidence for the existence of cosmic strings. The discovery of the increase of polarization rate in smaller subgroups of the several large-quasar groups (LQGs), the red shift dependency and the relative orientation of the spin axes with respect to the major axes of their host LQGs, point at a fractional azimuthal structure, were also found in our cosmic string model. This peculiar discontinuous large scale structure, i.e., polarizations directions of multiples of, for example,

关键词： quasar Polarization Cosmic Strings Warped Brane World Models U(1) Scalar-Gauge Field Multiple-Scale Analysis

Newly discovered bright high redshift z = 3.3 quasar by multi-color photometry

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Progress in Natural Science:Materials International 1998年第2期 3-5页

作者：张枚陈建生周旭严皞璟朱进蒋兆基李耀华 Beijing 100080 Beijing Astronomical Observatory China) Chinese Academy of Sciences

The origin and formation of the universe is a hot topic of modern astronomy. Since quasars have high redshifts and high luminosity, they can be used as the probe for studying the early universe. To search for high-red... 详细信息

关键词： multicolor photometry sky survey quasar high redshift.

IUE OBSERVATIONS OF quasar 0916+558

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Chinese Science Bulletin 1988年第13期33卷 1110-1113页

作者：程富华尤峻汉 Center for Astrophysics University of Science and Technology of China Hefei

*** A UV observation of QSO 0916+558 was made on October 10, 1985, using the short wavelength camera (SWP)in the low dispersion mode with the large 10″×20″aperture, having a resolution of (?). We obtained a spectru... 详细信息

关键词： ultraviolet spectrum quasar Cerenkov line emission intensity ratio

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quasar──内鼓武照排机的新成员

电子出版 1995年第9期 51-52页

Ｑｕａｓａｒ──内鼓武照排机的新成员１９９５年２月，连诺·海尔公司在竞争日益激烈的内鼓式照排机市场又投入了一颗重镑炸弹一Ｑｕａｓａｒ。Ｑｕａｓａｒ可以曝光两张Ａ４页面，特别适合海德堡ＧＴＯ等各种中等幅面的印刷机。它质... 详细信息

Ｑｕａｓａｒ──内鼓武照排机的新成员１９９５年２月，连诺·海尔公司在竞争日益激烈的内鼓式照排机市场又投入了一颗重镑炸弹一Ｑｕａｓａｒ。Ｑｕａｓａｒ可以曝光两张Ａ４页面，特别适合海德堡ＧＴＯ等各种中等幅面的印刷机。它质量高，速度快，标准配置包含打孔系统...

关键词：照排机新成员照相排字机 quasar 供片盒大力神海尔鼓式印版感光材料胶印机橡皮印刷机

USTC astronomers have measured the sizes of ～1000 quasar outflows

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Science Foundation in China 2019年第1期27卷 37-37页

Under the support of the National Natural Science Foundation of China,the research team led by *** TingGui(王挺贵)and *** GuiLin(刘桂琳)at the CAS Key Laboratory for Research in Galaxies and Cosmology,Department of Astronomy,University of Science and Technology of China(USTC),recently reported their novel method to measure the spatial scale of quasar outflows.

关键词： USTC astronomers measured quasar outflows