Grain-size measurements in protoplanetary disks indicate fragile pebbles and low turbulence Haochang Jiang, Enrique Macías, Osmar M. Guerra-Alvarado and Carlos Carrasco-González A&A, 682 (2024) A32 Published online: 02 February 2024 DOI: 10.1051/0004-6361/202348271