Discovery of 16 New z ∼ 5.5 Quasars: Filling In The Redshift Gap of Quasar Color Selection

NSFC [11373008, 11533001]; Strategic Priority Research Program "The Emergence of Cosmological Structures" of the Chinese Academy of Sciences [XDB09000000]; National Key Basic Research Program of China [2014CB845700]; Ministry of Science and Technology of China [2016YFA0400703]; U.S. NSF [AST 11-07682, AST 15-15115]; Chinese Academy of Sciences; People's Government of Yunnan Province; Strategic Priority Research Program "The Emergence of Cosmological Structures" [XDB09000000]; National Astronomical Observatories; Special Fund for Astronomy from the Ministry of Finance in China; Open Project Program of the Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences; Alfred P. Sloan Foundation; National Science Foundation; U.S. Department of Energy Office of Science; University of Arizona; Brazilian Participation Group; Brookhaven National Laboratory; University of Cambridge; Carnegie Mellon University; University of Florida; French Participation Group; German Participation Group; Harvard University; Instituto de Astrofisica de Canarias; Michigan State/Notre Dame/JINA Participation Group; Johns Hopkins University; Lawrence Berkeley National Laboratory; Max Planck Institute for Astrophysics; Max Planck Institute for Extraterrestrial Physics; New Mexico State University; New York University; Ohio State University; Pennsylvania State University; University of Portsmouth; Princeton University; Spanish Participation Group; University of Tokyo; University of Utah; Vanderbilt University; University of Virginia; University of Washington; Yale University; National Aeronautics and Space Administration