The Latest LAGER Cosmic Reionization Results: The 10 deg2 Lya Luminosity Function at z=6.9

Redshift z~7 is the sweet spot for Lya based reionization tests. It is where the effects of neutral gas are strong enough to be most readily observable, yet not so prevalent as to completely block Lya emission from our view. We are conducting a definitive 24 deg² narrowband Lya emitter (LAE) survey at z = 6.9 — The Lyman-Alpha Galaxies in the Epoch of Reionization (LAGER) project. This survey exploits DECam's uniquely large FOV and detector sensitivity in the near-infrared, as well as a custom-made narrowband filter at 9642 A. We present the latest LAGER results based on 150 Lya galaxies, with about 2 dozen spectroscopic confirmations, over a 10 deg² survey area. For luminous sources, we find field-to-field variations in the number density. We discuss the significance of these luminous sources that are found in LAE-overdense regions, and the implications of LAGER results for reionization.