The Nature of High Redshift Radio Source Hosts

钱伯斯高红移射电星系（HZRGs）是目前所知的最奇特、最遥远的天体之一，在当今宇宙中还没有类似的天体。最近的观测表明，它们由巨大的气体和尘埃区域组成，这些区域被各向异性类星体光束照亮，通过散射就像雾中的探照灯一样可见。被尘埃散射的光是偏振的，这使得这些天体成为研究天文尘埃和星系尘埃含量的宇宙演化的好地方。射电强、双叶、陡谱类星体（QSRs）是目前已知的最大的高红移扩展天体，对它们的运动学、尘埃含量和恒星种群的研究将有助于了解大质量星系的形成。本项目将对这些高红移射电源宿主进行研究。将采用两种新的观测方法：㈠将利用分辨率为50毫弧秒的8-10米级望远镜上的新一代自适应光学仪器，有针对性地研究在等晕斑内有明亮（M 13）前景恒星的遥远射电源样本。随着自适应光学系统的出现，人们有可能获得最遥远和最红星系的二维表面亮度分布和颜色梯度。扩展的发射线区域的积分场光谱可以与动力学和尘埃散射模型进行比较。空间分辨红外偏振测量将探测这些天体的尘埃含量及其随红移的演变。AO与自然导星提供的能力的巨大改进为推进遥远宇宙中的射电星系领域提供了一个至关重要的工具。(ii)一个宽视场光学成像偏振测量调查，这将是第一个深空调查，以寻找微弱的偏振物体。利用位于莫纳克亚山的斯巴鲁8米日本国家望远镜上的主焦点相机，深度偏振测量调查可以达到非常微弱的点源（大于29等）。对三个独立的0.5度场的观测将产生10万多个河外天体的线性偏振图像和目录，其中包括100多个微弱的射电星系。这些将与已知的无线电，亚毫米，X射线和红移目录，和HST形态交叉相关。这一宽视场成像偏振测量巡天将提供一个独特的和独立的测量方法，测量高红移的尘埃星系群的性质和演化，并测量尘埃和再处理光对高红移星系和活动星系核宿主的颜色和形态的影响。该项目的资金由美国国家科学基金会河外天文宇宙学计划（AST/EXC）提供。*

ABSTRACT AST 0098349ChambersHigh redshift radio galaxies (HZRGs) are among the strangest and most distant objects known, there is nothing like them in the universe today. Recent observations suggest that they consist of vast regions of gas and dust illuminated by an aniosotropic quasar beam that becomes visible by scattering like a searchlight in fog. The light scattered by dust is polarized, making these objects a good place to study astronomical dust and the cosmic evolution of the dust content of galaxies. Radio-loud, double-lobed, steep-spectrum quasars (QSRs) are the largest extended objects known at high redshift, and studies of their kinematics, dust content, and stellar populations will provide insight to the formation of massive galaxies.This project will study these high redshift radio source hosts. Two novel observational approaches will be used:(i) Targeted studies of a sample of distant radio sources that have bright (M 13) foreground stars within the isoplanatic patch will be observed with the new generation of adaptive optics instruments on 8-10 meter class telescopes with 50 milliarcsecond resolution. With the adaptive optics systems now available, it is possible to obtain two-dimensional surface brightness profiles and color gradients of the most distant and reddest galaxies. Integral field spectroscopy of the extended emission line regions can be compared with dynamical and dust scattering models. Spatially resolved infrared polarimetry will probe the dust content of these objects and its evolution with redshift. The vast improvement in capability provided by AO with natural guide stars provides a crucial tool to advance the field of radio galaxies in the distant universe.(ii) A wide field optical imaging polarimetry survey that will be the first deep sky survey to searchfor faint polarized objects. With the prime focus camera on the Subaru 8-meter Japanese National Telescope on Mauna Kea a deep polarimetry survey can reach very faint point sources (greater than 29th magnitude). Observations of three separate 0.5 degree fields, will produce images and a catalog of the linear polarization of more than 100,000 extragalactic objects, including more than 100 faint radio galaxies. These will be cross correlated with known radio, submillimeter, x-ray, and redshift catalogs, and HST morphologies. This wide field imaging polarimetry survey will provide a unique and independent measure of the nature and evolution of the dusty galaxy population at high redshift and measure the impact of dust and reprocessed light on the colors and morphologies of high redshift galaxies and AGN hosts.Funding for this project was provided by the NSF program for Extragalactic Astronomy & Cosmology (AST/EXC).***