Anne Jaskot's Research Website

The LzLCS:
The Low-redshift Lyman Continuum Survey

A Hubble Space Telescope (HST) Cycle 26 Large Program: HST-GO-15626 (PI Jaskot)

Which galaxies reionized the universe? What fraction of a galaxy’s ionizing, Lyman continuum (LyC) photons escape into the intergalactic medium? How do we identify galaxies with escaping ionizing radiation? Which galaxy properties regulate LyC escape?

As the largest reference sample of LyC measurements in low-redshift galaxies, the LzLCS is helping us answer these questions. These analyses can help us interpret James Webb Space Telescope (JWST) observations of galaxies in the epoch of reionization, where direct measurements of LyC are not feasible due to absorption by intergalactic gas.

Our LyC measurements and the main properties of the LzLCS galaxies have been published in Flury et al. (2022a) and Saldana-Lopez et al. (2022). We have also developed a python tool, available here, which uses the multivariate Cox proportional hazards model to predict LyC escape fractions for high-redshift galaxies using any desired combination of input variables. See Jaskot et al. (2024a) and (2024b) for more information.

An HST ultraviolet image (left) and spectrum (right) of a LyC-emitting galaxy from the LzLCS. Figure adapted from Flury et al. (2022). Credit: S. Flury/A. Jaskot.

An example of multivariate predictions for the LyC escape fraction, derived using the LzLCS. Figure from Jaskot et al. (2024a).

Publications by the LzLCS Team

Wang et al. (2021), "The Low-redshift Lyman-continuum Survey: [S II] Deficiency and the Leakage of Ionizing Radiation."

Flury et al. (2022a), "The Low-Redshift Lyman Continuum Survey I: New, Diverse Local Lyman Continuum Emitters."

Flury et al. (2022b), "The Low-Redshift Lyman Continuum Survey II: New Insights into LyC Diagnostics."

Marques-Chaves et al. (2022), "No correlation of the Lyman continuum escape fraction with spectral hardness."

Saldana-Lopez et al. (2022), "The Low-Redshift Lyman Continuum Survey: Unveiling the ISM properties of low-z Lyman continuum emitters."

Chisholm et al. (2022), "The far-ultraviolet continuum slope as a Lyman Continuum escape estimator at high redshift."

Xu et al. (2023), "The Low-redshift Lyman Continuum Survey: Optically Thin and Thick Mg II Lines as Probes of Lyman Continuum Escape."

Amorín et al. (2024), "Ubiquitous broad-line emission and the relation between ionized gas outflows and Lyman continuum escape in Green Pea galaxies."

Bait et al. (2024), "The Low-redshift Lyman Continuum Survey: Radio continuum properties of low-z Lyman continuum emitters."

Leclercq et al. (2024), "Linking Mg II and [O II] spatial distribution to ionizing photon escape in confirmed LyC leakers and non-leakers."

Jaskot et al. (2024a), "Multivariate Predictors of LyC Escape I: A Survival Analysis of the Low-redshift Lyman Continuum Survey."

Jaskot et al. (2024b), "Multivariate Predictors of LyC Escape II: Predicting LyC Escape Fractions for High-Redshift Galaxies."