Coexistence of Antisunward and Sunward Ion Cyclotron Waves in the Near-Sun Solar Wind: Excitation by the Proton Cyclotron Instability - Shi,C; Zhao,J; Liu,S; Xiao,F; Wu,Y; Bowen,TA; Livi,R; Bale,SD (ASTROPHYSICAL JOURNAL LETTERS, 2024)