Observed Ambient Gas-particle Partitioning of Tracers for Biogenic Oxidation. GABRIEL ISAACMAN-VANWERTZ, Lindsay Yee, Nathan Kreisberg, Rebecca Wernis, Joshua Moss, Susanne Hering, Suzane de Sá, Scot Martin, Lizabeth Alexander, Brett Palm, Weiwei Hu, Pedro Campuzano-Jost, Douglas Day, Jose-Luis Jimenez, Matthieu Riva, Jason Surratt, Juarez Viegas, Antonio O. Manzi, Eric Edgerton, Karsten Baumann, Rodrigo A. F. Souza, Paulo Artaxo, Allen H. Goldstein, University of California at Berkeley, Berkeley, CA, USA