Light Intensity and Light Source Influence on Secondary Organic Aerosol Formation for the <i>m</i>-Xylene/NO<sub><i>x</i></sub> Photooxidation System Bethany. Warren Chen. Song David R. Cocker 10.1021/es702985n.s001 https://acs.figshare.com/articles/journal_contribution/Light_Intensity_and_Light_Source_Influence_on_Secondary_Organic_Aerosol_Formation_for_the_i_m_i_Xylene_NO_sub_i_x_i_sub_Photooxidation_System/2923918 A series of <i>m</i>-xylene/NO<sub><i>x</i></sub> photooxidation experiments were conducted to determine the influence of light intensity and radiation spectrum on secondary organic aerosol (SOA) formation within the UC Riverside/CE-CERT environmental chamber. The environmental chamber is equipped with 80 115-W black lights and a variable voltage 200 kW argon arc lamp that emits a wavelength spectrum more similar to natural light. SOA formation increased significantly with light intensity, measured as the photolysis rate of NO<sub>2</sub> to NO (<i>k</i><sub>1</sub>), increased from 0.09 to 0.26 min<sup>−1</sup>. The argon arc lamp produced ∼20% more SOA than black lights at a <i>k</i><sub>1</sub> of 0.09 min<sup>−1</sup> for similar amounts of <i>m</i>-xylene consumed. These results may help explain the variation of SOA formation between environmental chambers and the differences between measured SOA in the ambient atmosphere versus environmental chamber predictions. 2008-08-01 00:00:00 light intensity voltage 200 kW argon arc lamp argon arc lamp chamber Secondary Organic Aerosol Formation Light Source Influence SOA formation UC