491 citations · 1.4k across the 24 of their papers we have counts for
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HST-COS Observations of AGNs. III. Spectral Constraints in the Lyman Continuum from Composite COS/G140L Data
Evan M. Tilton, Matthew L. Stevans, J. Michael Shull +1
The rest-frame ultraviolet (UV) spectra of active galactic nuclei (AGNs) are important diagnostics of both accretion disk physics and their contribution to the metagalactic ionizin…
The Metagalactic Ionizing Background: A Crisis in UV Photon Production or Incorrect Galaxy Escape Fractions?
J. Michael Shull, Joshua Moloney, Charles W. Danforth +1
Recent suggestions of a "photon underproduction crisis" (Kollmeier \etal\ 2014) have generated concern over the intensity and spectrum of ionizing photons in the metagalactic ultra…
The Efficiency of Stellar Reionization: Effects of Rotation, Metallicity, and Initial Mass Function
Michael W. Topping, J. Michael Shull
We compute the production rate of photons in the ionizing Lyman continua (LyC) of H I (lambda < 912 A), He I (lambda < 504 A), and He II (lambda < 228 A) using recent stellar evolu…