A Theoretical Exploration of Lyman-alpha Emitting Galaxies

Zheng Zheng

Utah

Lyman-alpha emitting galaxies or Lyman-alpha emitters (LAEs), galaxies selected by their Lyman-alpha emission, are becoming an important probe of galaxy formation, cosmic reionization, and cosmology. Correct interpretations of the growing observations of LAEs require a full consideration of the radiative transfer (resonant scattering) of Lya photons. I will present a theoretical investigation of LAEs based on radiative transfer modeling performed in cosmological simulations. The study reveals a coupling between the observed Lyman-alpha emission and the circumgalactic and intergalactic environments, induced by the resonant scattering of Lyman-alpha photons. I will show that such an environment-dependent radiative transfer effect helps to explain many observational properties of LAEs. Furthermore, it gives rise to interesting features in the clustering of LAEs, which leads to a new type of potentially strong distortions of non-gravitational origin in galaxy clustering. Finally, I will discuss the challenges and opportunities in using LAEs to study structure formation and cosmology.