The Low-redshift Lyman Continuum Survey. II. New Insights into LyC Diagnostics

Sophia R. Flury, Anne E. Jaskot, Harry C. Ferguson, Gábor Worseck, Kirill Makan, John Chisholm, Alberto Saldana-Lopez, Daniel Schaerer, Stephan R. McCandliss, Xinfeng Xu, Bingjie Wang, M. S. Oey, N. M. Ford, Timothy Heckman, Zhiyuan Ji, Mauro Giavalisco, Ricardo Amorín, Hakim Atek, Jeremy Blaizot, Sanchayeeta BorthakurCody Carr, Marco Castellano, Stephane De Barros, Mark Dickinson, Steven L. Finkelstein, Brian Fleming, Fabio Fontanot, Thibault Garel, Andrea Grazian, Matthew Hayes, Alaina Henry, Valentin Mauerhofer, Genoveva Micheva, Goran Ostlin, Casey Papovich, Laura Pentericci, Swara Ravindranath, Joakim Rosdahl, Michael Rutkowski, Paola Santini, Claudia Scarlata, Harry Teplitz, Trinh Thuan, Maxime Trebitsch, Eros Vanzella, Anne Verhamme

Research output: Contribution to journalArticlepeer-review

61 Scopus citations


The Lyman continuum (LyC) cannot be observed at the epoch of reionization (z ≈ 6) owing to intergalactic H i absorption. To identify LyC emitters (LCEs) and infer the fraction of escaping LyC, astronomers have developed various indirect diagnostics of LyC escape. Using measurements of the LyC from the Low-redshift Lyman Continuum Survey (LzLCS), we present the first statistical test of these diagnostics. While optical depth indicators based on Lyα, such as peak velocity separation and equivalent width, perform well, we also find that other diagnostics, such as the [O iii]/[O ii] flux ratio and star formation rate surface density, predict whether a galaxy is an LCE. The relationship between these galaxy properties and the fraction of escaping LyC flux suggests that LyC escape depends strongly on H i column density, ionization parameter, and stellar feedback. We find that LCEs occupy a range of stellar masses, metallicities, star formation histories, and ionization parameters, which may indicate episodic and/or different physical causes of LyC escape.

Original languageEnglish (US)
Article number126
JournalAstrophysical Journal
Issue number2
StatePublished - May 1 2022

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'The Low-redshift Lyman Continuum Survey. II. New Insights into LyC Diagnostics'. Together they form a unique fingerprint.

Cite this