Spatial-Kinematic Absorption Models of the Circumgalactic Medium. II. Ionized Gas Phases and Absorption Lines

TL;DR

This paper introduces a flexible mathematical model for simulating quasar absorption lines from the ionized gas in the circumgalactic medium, aiding the study of galaxy baryon cycles and absorption systems.

Contribution

It extends previous work by incorporating multiphase ionized gas into spatial-kinematic models of the CGM for absorption line synthesis.

Findings

Developed formalism for populating CGM with ionized gas

Generated example HI and metal-line absorption profiles

Created a user-friendly GUI for model application

Abstract

In this two-paper series, we present a straightforward mathematical model for synthesizing quasar absorption line profiles from sight lines through idealized, spatial-kinematic models of the circumgalactic medium (CGM) and their host galaxies. In Paper I, we developed the spatial components of the galaxy/CGM structures (disk, halo, wind, accretion) and their 3D velocity fields. We derived the formalism for arbitrary observed orientation of the galaxy/CGM model and quasar line of sight positioning. In this paper, following a brief review of Paper I, we present the formalism for populating the galaxy/CGM structures with multiphase photoionized and collisionally ionized gas and for generating HI and metal-line absorption profiles. Example absorption line systems through a fiducial galaxy/CGM model are presented. These flexible spatial-kinematic absorption models (SKAMs) can be directly applied to and/or easily modified/expanded for studying individual or ensembles of observed absorption line systems, for exploring various competing theoretical scenarios of the baryon cycle as studied through quasar absorption line systems, and/or serving as pedagogical tools for developing physical intuition. We briefly describe a SKAM GUI that is in early stages of development.