DECam Community Science Workshop 2018: Science Highlights, Coming Opportunities, LSST Synergies
May 21-22, 2018 • Tucson, Arizona
Looking for Bubbles in LAGER
Because Lyman alpha photons are scattered by neutral hydrogen, the visibility of Lyman alpha emitting galaxies serves as a proxy indicator for locations of ionized gas in the intergalactic medium. The numbers of Lyman alpha galaxies recently discovered in the LAGER (Lyman Alpha Galaxies in the Epoch of Reionization) survey are appreciably lower than seen at lower redshifts, suggesting that the intergalactic medium at redshift 7 is partially neutral. By studying the spatial distribution of the galaxies that are observed, we can look for individual ionized bubbles. We present evidence that such bubbles have been identified in LAGER. Moreover, we argue that the ionizing photon production in the region near the brightest LAGER sources should be approximately sufficient to ionize their surroundings regardless of the bulk ionization state of the redshift seven universe.
Authors: Sangeeta Malhotra, James E. Rhoads, Zhenya Zheng, and the LAGER collaboration