1. Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
2. Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
3. Department of Atmospheric and Oceanic Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
4. Atmospheric Chemistry Observations and Modeling, National Center for Atmospheric Research, Boulder, Colorado 80301, United States
5. Department of Chemistry and Biochemistry, University of Montana, Missoula, Montana 59812, United States
6. Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 80521, United States
7. Department of Atmospheric Sciences, University of Washington, Seattle, Washington 98195, United States