1. Department for Astrophysical and Planetary Science, University of Colorado , Boulder, CO 80309, USA
2. Department of Astronomy and Astrophysics, University of California , Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA
3. Kavli Institute for Particle Astrophysics and Cosmology and Department of Physics, Stanford University , Stanford, CA 94305, USA
4. Department of Astronomy, University of Florida , 211 Bryant Space Sciences Center, Gainesville, FL 32611, USA
5. Center for Astrophysics | Harvard & Smithsonian , 60 Garden Str, Cambridge, MA 02138, USA
6. Center for Astrophysics, Harvard University , Cambridge, MA 02138, USA
7. Department of Physics and Astronomy and PITT PACC, University of Pittsburgh , Pittsburgh, PA 15260, USA
8. Fermi National Accelerator Laboratory , Batavia, IL 60510, USA
9. Max-Planck-Institut für Astronomie , K’onigstuhl 17, D-69117 Heidelberg, Germany
10. Center for Astrophysics, Harvard & Smithsonian , 60 Garden Str, Cambridge, MA, 02138, USA
11. Department of Astronomy, Van Vleck Observatory, Wesleyan University , 96 Foss Hill Drive, Middletown, CT 06459, USA
12. Department of Astronomy, University of Massachusetts , Amherst, MA 01003, USA
13. Cosmic Dawn Center (DAWN) ,Rådmandsgade 62, 2200 København, Denmark
14. Steward Observatory, University of Arizona , 933 North Cherry Avenue, Tucson, AZ 85721, USA
15. NSF’s National Optical-Infrared Astronomy Research Laboratory , 950 North Cherry Avenue, Tucson, AZ 85719, USA