Mutual events in the Cold Classical transneptunian binary system Sila and Nunam

a Lowell Observatory, Flagstaff, AZ 86001, United States Carnegie Institution of Washington, Department of Terrestrial Magnetism, Washington, DC 20015, United States Center for Astronomy and Astrophysics, Yale University, New Haven, CT 06520, United States NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States Department of Astronomy, University of Virginia, Charlottesville, VA 22904, United States f Southwest Research Institute, Boulder, CO 80302, United States Astronomy Department, Yale University, New Haven, CT 06520, United States Department of Physics and Astronomy, Brigham Young University, Provo, UT 84602, United States