1. Department of Astronomy, University of Virginia, Charlottesville, VA 22904, USA
2. Department of Astronomy, Ohio State University, Columbus, OH 43210, USA
3. National Radio Astronomy Observatory, Charlottesville, VA 22904, USA
4. Department of Physics, Engineering Physics and Astronomy, Queen’s University, Kingston, ON K7L 3N6, Canada
5. Department of Astronomy & Astrophysics, University of Toronto, Toronto, ON M5S 3H4, Canada
6. Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching, Germany
7. Department of Astronomy, University of Florida, Gainesville, FL 32611, USA
8. Herzberg Astronomy and Astrophysics, National Research Council of Canada, Victoria, BC V9E 2E7, Canada
9. Department of Astronomy, University of Arizona, Tucson, AZ 85721, USA
10. Ural Federal University, Mira St 19, Yekaterinburg 620002, Russia
11. Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 5C2, Canada
12. Department of Physics, University of Alberta, Edmonton, AB T6G 2E1, Canada
13. Department of Astronomy, University of Texas at Austin, Austin, TX 78712, USA
14. Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, ON M5S 3H8, Canada
15. Observatorio Astronómico Nacional (OAN-IGN), Alfonso XII 3, E-28014 Madrid, Spain
16. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
17. Department of Astronomy, Yale University, New Haven, CT 06520, USA
18. Harvard–Smithsonian Center for Astrophysics, Cambridge, MA 02138, USA