A Lyman Alpha Galaxy at Redshift z=6.944 in the COSMOS Field
  Lyman-alpha emitting galaxies can be used to study cosmological reionization,
because a neutral intergalactic medium scatters Lyman-alpha photons into
diffuse halos whose surface brightness falls below typical survey detection
limits. Here we present the Lyman-alpha emitting galaxy LAE
J095950.99+021219.1, identified at redshift z=6.944 in the COSMOS field using
narrowband imaging and followup spectroscopy with the IMACS instrument on the
Magellan I Baade telescope. With a single object spectroscopically confirmed so
far, our survey remains consistent with a wide range of IGM neutral fraction at
redshift seven, but further observations are planned and will help clarify the
situation. Meantime, the object we present here is only the third Lyman-alpha
selected galaxy to be spectroscopically confirmed at redshift seven, and is
2--3 times fainter than the previously confirmed redshift seven Lyman alpha
galaxies.
