1. Center for Aerosol and Cloud Chemistry, Aerodyne Research, Inc., 45 Manning Rd., Billerica, Massachusetts 01821
2. Department of Chemistry and CIRES, University of Colorado‐Boulder, Boulder, Colorado 80309
3. School of Earth, Atmospheric and Environmental Sciences, University of Manchester, England
4. Paul Scherrer Institut, Villigen, Switzerland
5. Atmospheric Sciences Research Center, State University of New York, Department of Earth and Atmospheric Sciences, University at Albany, Albany, New York 12222
6. Max Planck Institute for Chemistry, Particle Chemistry Department, 55128 Mainz, Germany
7. NOAA Earth System Research Laboratory, Boulder, Colorado 80305
8. Program in Atmospheric and Oceanic Science, University of Colorado, Boulder, Colorado 80309
9. Chemistry Department, Boston College, Chestnut Hill, Massachusetts 02467