Main Questions and Interests

My research falls under three main questions:

  • How was the universe reionized, and what were the sources that caused this?
  • What are the properties of the circumgalactic medium of galaxies?
  • How do galaxy winds and outflows work?

My work is mostly observational. I lead and contribute to some of the largest projects ongoing with James Webb Space Telescope (JWST), Hubble Space Telescope (HST), and ESO Very Large Telescope (VLT). Future developments in which I am involved include:

Legacy Survey of Space and Time / Vera C. Rubin Observatory, I am one of the European project PIs and project manager for the OKC contribution.

VLT/BlueMUSE: the next-generation large-format IFU, optimized for blue wavelengths.

ELT/MOSAIC: the highly multiplexed optical/NIR spectrograph and IFU at ESOs Extremely Large Telescope, where I am chair of the First Light/EoR working group.

Mirror-slicer Array for Astronomical Transients (MAAT) for the GTC.

The best way to explore these issues is to obtain datasets that answer many questions simultaneously.

Main Projects and Collaborations

Parallel Application of Slitless Spectroscopy for Galaxy Evolution (PASSAGE)

The largest JWST program in Cycle 1 at 591 hours. PASSAGE will survey for high redshift galaxies on 120 pointings. Watch the PI talk about it here:

Imaging of starburst galaxies

I serve as Principal Investigator for Large HST Program in Cycle 30 to obtain five-band Hubble imaging of 41 starburst galaxies with and without LyC emission. We will study their circumgalactic media, morphologies and star formation histories. I have served as PI and co-PI for a number of similar programs in the past: e.g. Lyman alpha halo imaging, and the Lyman alpha Reference Sample (LARS).

Metal emission line imaging of starburst galaxies

I led some HST programs to produce the first emission line images of starburst galaxies in warm gas using OVI emission. E.g. Hayes et al (2016). We are currently applying similar techniques to image CIV.

Ultraviolet Spectroscopic Databases

I maintain a database of over 200 UV spectra from HST/COS, to study the evolution of Lyman alpha sepctral profiles and the development of galaxy superwinds. I serve as PI for an ongoing Large Program with ESO/VLT to obtain extremely deep, high resolution spectra of 300 galaxies in the EoR.

The Parallel Ionizing Emissivity Survey (PIE)

PIE is a very large (400 orbit) ongoing HST program to measure the ionizing emissivity of redshift 3 Lyman Break Galaxies.

COS Legacy Archive Spectroscopic SurveY (CLASSY)

CLASSY is a large treasury (135+177 orbit) HST program to provide a deep set of reference spectra to interpret high-z galaxies observed with JWST. The objectives are to understand the properties of the massive stars, galaxy winds and outflows, Lyman alpha emission profiles, and highly ionized interstellar medium. See the data release and survey paper.

The Low Redshift Lyman Continuum Survey (LzLCS)

LzLCS is a Large HST/COS program to measure the ionizing output of a sample of low-redshift star-forming galaxies. The survey has over-tripled the number of known LyC-leakers, and transformed our understanding of LyC emission. Read the main survey papers, Flury et al (2022a; Paper I) and (2022b; Paper II).

Very Deep Ultraviolet imaging -- UVCANDELS

The Ultraviolet Imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Fields (UVCANDELS) is a Large Treasury HST survey, providing deep HST UV imaging of the premier HST deep survey fields. The goals are to study the structural evolution of galaxies, the impact of dust attenuation, the role of environment in galaxy evolution, and the ioinzing output of galaxies.