Content may be subject to copyright.This is a pre-copyedited, author-produced PDF of an article accepted for publication in International Mathematics Resear... ...This is a pre-copyedited, author-produced PDF of an article accepted for publication in International Mathematics Research Notices following peer review. The version of record [Resonances and Scattering Poles in Symmetric Spaces of Rank One. International Mathematics Research Notices 2019, 20 p6362-6389 (2019)] is available online at: https://doi.org/10.1093/imrn/rnx311.