TIPSY: Trajectory of Infalling Particles in Streamers around Young stars - Dynamical analysis of the streamers around S CrA and HL TauAashish Gupta, Anna Miotello, Jonathan P. Williams, Til Birnstiel, Michael Kuffmeier and Hsi-Wei YenA&A, 683 (2024) A133DOI: https://doi.org/10.1051/0004-6361/202348007