Reinvestigation of the unified theory for Seyfert galaxies by observing water vapor masers

通过观测水蒸气微波激射器重新研究赛弗特星系统一理论

• 批准号: 17340052
• 负责人: NAKA Naomasa
• 金额: $ 9.02万
• 依托单位: University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17340052/
• 关键词: astronomical observations; radio astonomy; radio telescopes; galaxies; active galactic nuclei; black holes; メーザー; 銀河形成進化; 宇宙物理; 宇宙論; 宇宙メーザー; セイファート銀河

(1) The 20-GHz band observing system of the Tsukuba 32-m telescope of the Geographical Survey Institute was newly constructed to make observations of water-vapor maser emission in the nuclear regions of Seyfert galaxies. The HPBW of the telescope was 100" at 22 GHz, and the main beam efficiency and the aperture efficiency were 0.52 and 0.40, respectively The receiver frontend was a HEMT amplifier cooled at 20 K and had sensitivity at the radio frequencies of 19.5 - 25.2 GHz. The intermediate frequencies were 4 - 8 GHz. A spectrometer was the Fourier transformation-type digital spectrometer with the frequency band of 1 GHz and the channel number of 16 k. The system noise temperature including the atmosphere and ohmic loss was 60-80 K at the zenith. The system is useful to study the nuclear regions of Seyfert galaxies by observing water-vapor maser emission.(2) We started monitoring observations of velocities of water masers from Seyfert galaxies. In addition, we revealed that a maser disk at the center of a type 2 Seyfert, IC 1481, was thick and massive, confirming our hypothesis in which the difference between the type 1 and 2 of Seyfert galaxies is caused by not only the viewing angle of the accretion disk but also the thickness of the disk.

(1)地理调查研究所的筑波32米望远镜的20千兆赫波段观测系统是新建成的，用于观测塞弗特星系核区的水汽脉泽发射。该望远镜在22 GHz处的高带宽为100 ″，主波束效率和口径效率分别为0.52和0.40。接收机前端为HEMT放大器，制冷温度为20 K，灵敏度为19.5 - 25.2GHz。中频为4 - 8 GHz。光谱仪是具有1GHz频带和16 k通道数的傅里叶变换型数字光谱仪。天顶处的系统噪声温度（包括大气和欧姆损耗）为60-80 K。该系统对通过观测水汽脉泽辐射来研究塞弗特星系的核区是有用的。(2)我们开始监测塞弗特星系水脉泽的速度观测。此外，我们发现，微波激射盘在中心的2型塞弗特，IC 1481，是厚和质量，证实了我们的假设，即1型和2型塞弗特星系之间的差异是造成的，不仅是吸积盘的视角，但也盘的厚度。

项目成果

つくば32m電波望遠鏡の単一鏡観測制御システムの開発

筑波32m射电望远镜单镜观测控制系统的开发

• 发表时间: 2008
• 作者: Seta;M.;et. al.;瀬田益道;山内彩
• 通讯作者: 山内彩

汎用計算機を用いた広帯域ソフトウエアー電波分光計の開発

使用通用计算机开发宽带软件无线电频谱仪

• 发表时间: 2006
• 作者: 丸山理樹;中井直正;瀬田益道;他;萩原健三郎
• 通讯作者: 萩原健三郎

Performance of the Tsukuba 32-m antenna at the 20-GHz band

筑波 32 米天线在 20 GHz 频段的性能

• 发表时间: 2008
• 作者: Maruyama;T.;et. al.
• 通讯作者: et. al.

Emergence of a Narrow H2O Maser Feature in NGC 1052

NGC 1052 中窄 H2O 脉泽特征的出现

• 发表时间: 2005
• 期刊: The Astrophysical Journal 620
• 作者: Negami;Seiya;S.Kameno
• 通讯作者: S.Kameno

Water-Vapor Maser Survey for Active Galactic Nuclei : A Megamaser in NGC 6926

活跃星系核的水蒸气脉泽巡天：NGC 6926 中的巨型脉泽

• 发表时间: 2005
• 期刊: Publications of the Astronomical Society of Japan 57
• 作者: Sato;N.;Yamauchi;A.;Ishihara;Y.;Sorai;K.;Kuno;N.;Nakai;N.;Balasubramanyam;R.;Hall;P.
• 通讯作者: P.