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On the M-σ Relationship and SMBH Mass Estimates of Selected Nearby Galaxies

International Journal of Astronomy and Astrophysics 2013年第3期3卷 1-9页

作者： Alper K.Ates Can Battal Kilinc Cafer Ibanoglu Astronomy and Space Sciences Department Ege UniversityIzmirTurkey

Super massive black holes are believed to influence galactic evolution and dynamics. A histogram of SMBH masses for different redshift regimes may reveal clues on how the SMBH evolve in time. A prominent method for SMBH mass estimation is based on the linear correlation between the bulge velocity dispersion and the SMBH mass. Known as M-σ relationship, this method is known to provide reasonable but not very accurate mass estimates due to considerable scatter in data. In order to increase the precision, we surveyed the literature and gathered SMBH and velocity dispersion data for low redshift (z 0.02) spiral galaxies. We report the M-σ relationship for low redshift spiral galaxies as, By using this refined M-σ relationship we measured 32 SMBH masses and determined upper and lower mass boundaries and the mass histogram for spiral galaxies in a narrow redshift regime (0.016 z < 0.017). The spectroscopic data are obtained from The SLOAN Digital Survey and The National Observatory of Turkey (TUG). The targets are selected within a low redshift range for discernible [OIII] lines. TUG observations are carried out on the RTT150 1.5 m telescope using TUG Faint Object Spectrographic Camera and the SLOAN data are obtained from the 7th data release of the survey. We measured the bandwidths of narrow [OIII] lines, which are shown to be indicative in estimating stellar bulge velocity dispersion and estimated the central black hole masses from the refined version of the empirical M-σ relationship. The estimated masses vary between 9.51 × 106 - 2.36 × 108 solar masses.

关键词： Galaxies Active Galaxies AGN SMBH Stellar Velocity Dispersion Bulge Velocity Dispersion

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Galaxy Interactions in Filaments and Sheets:Effects of the Large-scale Structures Versus the Local Density

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Research in Astronomy and Astrophysics 2023年第2期23卷 197-204页

作者： Apashanka Das Biswajit Pandey Suman Sarkar Department of Physics Visva-Bharati UniversitySantiniketanBirbhum731235India Department of Physics Indian Institute of Science Education and Research TirupatiTirupati-517507Andhra PradeshIndia

Major interactions are known to trigger star formation in galaxies and alter their *** study the major interactions in filaments and sheets using SDSS data to understand the influence of large-scale environments on galaxy *** identify the galaxies in filaments and sheets using the local dimension and also find the major pairs residing in these *** star formation rate(SFR) and color of the interacting galaxies as a function of pair separation are separately analyzed in filaments and *** analysis is repeated for three volume limited samples covering different magnitude *** major pairs residing in the filaments show a significantly higher SFR and bluer color than those residing in the sheets up to the projected pair separation of~50 *** observe a complete reversal of this behavior for both the SFR and color of the galaxy pairs having a projected separation larger than 50 *** earlier studies report that the galaxy pairs align with the filament *** alignment inside filaments indicates anisotropic accretion that may cause these *** do not observe these trends in the brighter galaxy *** pairs in filaments and sheets from the brighter galaxy samples trace relatively denser regions in these *** absence of these trends in the brighter samples may be explained by the dominant effect of the local density over the effects of the large-scale environment.

关键词： methods statistical-methods data analysis-galaxies evolution-galaxies interactions-(cosmology:)large-scale structure of universe

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Do Minor Interactions Trigger Star Formation in Galaxy Pairs?

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天文和天体物理学研究:英文版 2023年第9期23卷 322-340页

We analyze the galaxy pairs in a set of volume limited samples from the Sloan Digital Sky Survey to study the effects of minor interactions on the star formation rate(SFR)and color of *** carefully design control samples of isolated galaxies by matching the stellar mass and redshift of the minor *** SFR distributions and color distributions in the minor pairs differ from their controls at>99%significance *** also simultaneously match the control galaxies in stellar mass,redshift and local density to assess the role of the *** null hypothesis can be rejected at>99%confidence level even after matching the *** analysis shows a quenching in the minor pairs where the degree of quenching decreases with the increasing pair separation and plateaus beyond 50 *** also prepare a sample of minor pairs with Hαline *** calculate the SFR of these galaxies using the Hαline and repeat our *** observe a quenching in the Hαsample *** find that the majority of the minor pairs are quiescent systems that could be quenched due to minor *** data from the Galaxy Zoo and Galaxy Zoo 2,we find that only∼1%galaxies have a dominant bulge,4%–7%galaxies host a bar and 5%–10%of galaxies show active galactic nucleus(AGN)activity in minor *** indicates that the presence of bulge,bar or AGN activity plays an insignificant role in quenching the galaxies in minor *** more massive companion satisfies the criteria for mass quenching in most of the minor *** propose that the stripping and starvation likely caused the quenching in the less massive companion at a later stage of evolution.

关键词： methods statistical-galaxies formation-methods data analysis-galaxies interactions-galaxies star formation-(cosmology )large-scale structure of universe

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美国亚利桑那洲比斯卑铜矿坑附近重金属浓度的环境评价(英文)

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沈阳化工学院学报 2008年第1期22卷 88-95页

作者：鲍勃.威尔逊布莱恩.皮亚特诺丁汉特伦特大学理学院跨学科生物医学研究中心

铜矿坑位于亚历桑那州古老的铜矿区,24 a的过度性开采,产生了大量的尾矿和熔炼矿渣,采矿和熔炼活动造成大片地区的重金属污染.文章通过收集和分析铜矿坑附近植物与土壤样本,研究盛行风引起的重金属扩散污染情况,确定下风向工作位点上Cd... 详细信息

铜矿坑位于亚历桑那州古老的铜矿区,24 a的过度性开采,产生了大量的尾矿和熔炼矿渣,采矿和熔炼活动造成大片地区的重金属污染.文章通过收集和分析铜矿坑附近植物与土壤样本,研究盛行风引起的重金属扩散污染情况,确定下风向工作位点上Cd、Cu、Pb和Zn的浓度以及地形和距离对扩散的影响.此外还讨论了重金属通过不同水平的营养代谢在生物体内的蓄积,并对过去和现在颗粒污染物和受污染的动物的摄入可能引起的人类健康问题进行了探讨.

关键词：生物积累扩散人类健康重金属采矿

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终结性与“（是）……的”焦点结构

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语言文字学 2012年第8期 120-140页

作者：麦子茵

本文从事件的终结性的角度来考察“（是）……的”焦点结构在句法和语义上的种种限制，并用语感判断数据和语言事实证明“（是）……的”焦点结构只能用于描述终结性事件（telic event）。事件的终止点必须停留在该结构的预设中，不能... 详细信息

本文从事件的终结性的角度来考察“（是）……的”焦点结构在句法和语义上的种种限制，并用语感判断数据和语言事实证明“（是）……的”焦点结构只能用于描述终结性事件（telic event）。事件的终止点必须停留在该结构的预设中，不能提取成为焦点。本文的讨论将证明终结性这一概念的引入能够揭示“（是）……的”焦点句在信息结构方面一些尚未讨论过的特点，同时为各种格式的“（是）……的”焦点句提供更为简洁和统一的语义解释。

关键词： “(是)……的”焦点结构终结性话题焦点预设受影响者

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