My research aims to understand two facets of galaxy evolution:

• How do gas phase properties trace the evolution of the galaxy?
• What can chemical abundance patterns of stars and gas tell us about the previous state of the galaxy?

One method to study both these questions uses absorption lines imprinted on a quasar spectrum. These absorption systems arise from foreground galaxies in front of distant quasars (relative to us).

DLAs in High Resolution

I have focused on using a class of quasar absorption line systems called damped Lyman alpha systems (DLAs) and subDLAs, which probe the largest concentrations of neutral hydrogen gas across a large range of cosmic time. My studies of the detailed chemical makeup of DLAs provide an alternative approach to studying the chemical evolution of the Universe that is typically probed through the abundance patterns in local stars. I am the PI of the ESPRESSO Quasar Absorption Legacy Survey (EQUALS), where we are observing 24 quasars with the ESPRESSO spectrograph in order to characterise high redshift gas in ultra-high spectral resolution, including assessing the temperature of the intergalactic and circumgalactic media, measuring the isotopic ratio of carbon and magnesium across cosmic time, and studying the chemical abundances of metal-poor absorption.

XQ-100 Survey

I am also a core group member of the XQ-100 legacy Survey (PIL S. Lopez). The survey observed 100 quasars with the X-Shooter spectrograph on the Very Large Telescope in Chile. I provided continuum fits on all spectra, and am heavily involved with the DLA science team, where I have worked on the selection of DLA systems with Mg II, as well as furthering my previous work on the chemistry of DLAs (including discovery of a metal-poor DLA).

The Cirucmgalactic Medium Surrounding Active Galactic Nuclei

One of the big components of my PhD thesis was studying the gaseous haloes surrounding galaxies (a.k.a the circumgalactic medium or CGM) using quasar absorption lines. Using the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST), I am studying how these gaseous reservoirs change when you have an actively accreting black hole (AGN) at the centre of the galaxy. I am currently the PI of the C IV in L* galaxies (CIViL*) survey with HST/COS, which is providing a census of C IV around L* galaxies in the COS-Halos and COS-GASS surveys. In addition to identifying the radial profile of C IV in the CGM around L* galaxies, we will be investigating how the C IV content of AGN hosts compare to their non-AGN counterparts.

Publications

A list of my publications can be found here.