Quasars Probing Quasars

本项目旨在通过分析近距离类星体对的光谱，研究星系间介质（IGM）、类星体演化和星系形成等问题。现有的数据集由100多对组成，可以在此资助期间进行广泛的探索，包括：1)研究红移2至3的IGM热历史；2)首次在几百kpc到几个Mpc的尺度上提供横向邻近效应的可靠测量；3)在拥有发光类星体的大质量高红移星系中研究晕星际介质的物理状态。该项目将评估明亮、红移2到4的类星体在撞击参数为几十到几百kpc时的化学丰度、电离状态、密度和气体的运动学。这些观测将告诉我们大质量星系形成的过程和类星体在高红移时反馈的本质。这项工作更广泛的影响包括培训从西班牙裔服务机构招募的本科生、研究生和博士后，以及公共宣传活动。

The purpose of this project is to research problems on the intergalactic medium (IGM), quasar evolution, and galaxy formation by analyzing the spectra of close quasar pairs. The existing dataset, comprised of over 100 pairs, enables a wide range of exploration in this grant period, including 1) Investigating the thermal history of the IGM at redshifts of 2 to 3; 2) Providing the first robust measure of the transverse proximity effect on scales of a few hundred kpc to several Mpc; and 3) Studying the physical state of the halo interstellar medium in the massive, high-redshift galaxies that host luminous quasars. The program will assess the chemical abundances, ionization state, density, and kinematics of the gas at impact parameters of tens to hundreds of kpc from bright, redshift 2 to 4 quasars. These observations will inform the processes of massive galaxy formation and the nature of quasar feedback at high redshift.Broader impacts of the work include training of undergraduate students recruited from a Hispanic Serving Institution, graduate students, and a postdoc, and public outreach activities.