title: Hydroxyl radical-induced formation of highly oxidized organic compounds.
abstract: Explaining the formation of secondary organic aerosol is an intriguing question in atmospheric sciences because of its importance for Earth's radiation budget and the associated effects on health and ecosystems. A breakthrough was recently achieved in the understanding of secondary organic aerosol formation from ozone reactions of biogenic emissions by the rapid formation of highly oxidized multifunctional organic compounds via autoxidation. However, the important daytime hydroxyl radical reactions have been considered to be less important in this process. Here we report measurements on the reaction of hydroxyl radicals with α- and β-pinene applying improved mass spectrometric methods. Our laboratory results prove that the formation of highly oxidized products from hydroxyl radical reactions proceeds with considerably higher yields than previously reported. Field measurements support these findings. Our results allow for a better description of the diurnal behaviour of the highly oxidized product formation and subsequent secondary organic aerosol formation in the atmosphere.
authors.affiliation: Leibniz-Institut für Troposphärenforschung (TROPOS), Permoserstraße 15, 04318 Leipzig, Germany.
authors.forename: Torsten
authors.initials: T
authors.lastname: Berndt
authors.affiliation: Leibniz-Institut für Troposphärenforschung (TROPOS), Permoserstraße 15, 04318 Leipzig, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Richters
authors.affiliation: Department of Physics, University of Helsinki, Helsinki 00014, Finland.
authors.forename: Tuija
authors.initials: T
authors.lastname: Jokinen
authors.affiliation: Department of Chemistry, University of Helsinki, Helsinki 00014, Finland.
authors.forename: Noora
authors.initials: N
authors.lastname: Hyttinen
authors.affiliation: Department of Chemistry, University of Helsinki, Helsinki 00014, Finland.
authors.forename: Theo
authors.initials: T
authors.lastname: Kurtén
authors.affiliation: Department of Chemistry, University of Copenhagen, Copenhagen 2100, Denmark.
authors.forename: Rasmus V
authors.initials: RV
authors.lastname: Otkjær
authors.affiliation: Department of Chemistry, University of Copenhagen, Copenhagen 2100, Denmark.
authors.forename: Henrik G
authors.initials: HG
authors.lastname: Kjaergaard
authors.affiliation: Leibniz-Institut für Troposphärenforschung (TROPOS), Permoserstraße 15, 04318 Leipzig, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Stratmann
authors.affiliation: Leibniz-Institut für Troposphärenforschung (TROPOS), Permoserstraße 15, 04318 Leipzig, Germany.
authors.forename: Hartmut
authors.initials: H
authors.lastname: Herrmann
authors.affiliation: Department of Physics, University of Helsinki, Helsinki 00014, Finland.
authors.forename: Mikko
authors.initials: M
authors.lastname: Sipilä
authors.affiliation: Department of Physics, University of Helsinki, Helsinki 00014, Finland.
authors.forename: Markku
authors.initials: M
authors.lastname: Kulmala
authors.affiliation: Department of Physics, University of Helsinki, Helsinki 00014, Finland.
authors.forename: Mikael
authors.identifier: 0000-0002-0215-4893
authors.initials: M
authors.lastname: Ehn