¹ Princeton University Observatory, Peyton Hall, Princeton, NJ 08544
² Department of Physics and Astronomy, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2686
³ Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721
⁴ Department of Physics and Astronomy, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
⁵ Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510
⁶ School of Physics and Astronomy, Southampton University, Southampton SO17 1BJ, UK
⁷ Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802
⁸ Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195
⁹ Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801-3080
¹⁰ Microsoft Research, 301 Howard Street, No. 830, San Francisco, CA 94105
¹¹ Astronomy Centre, University of Sussex, Falmer, Brighton BN1 9QJ, UK
¹² Institute for Astronomy, Royal Observatory, University of Edinburgh, Blackford Hill, Edinburgh EH9 3HJ, UK
¹³ Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637
¹⁴ Enrico Fermi Institute, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637
¹⁵ Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349
¹⁶ Institute for Cosmic Ray Research, University of Tokyo, 5-1-5 Kashiwa, Kashiwa City, Chiba 277-8582, Japan
¹⁷ Obserwatorium Astronomiczne na Suhorze, Akademia Pedagogicazna w Krakowie, ulica Podchorażych 2, PL-30-084 Kraków, Poland
¹⁸ Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 50R-5032, Berkeley, CA 94720-8160