Nebular Hα Limits for Fast Declining SNe Ia

Korea Astronomy and Space Science Institute (Republic of Korea) [GN-2008A-Q-17, GS-2018A-Q-315]; NSF [AST-1615455, AST-1821987, 1821967, AST-1515559]; NASA grant [ADAP-80NSSC19K0578]; DIRAC Institute in the Department of Astronomy at the University of Washington