ACROSS_LISA_PRG_ACSM-nrPM1comp_6-min_v1_L2

The aerosol particle non–refractory mass concentration of organic, nitrate, sulfate, ammonium and chloride was measured at the ground–based PRG urban site during ACROSS with a Time–of–Flight Aerosol Chemical Speciation Monitor (TOF–ACSM, Aerodyne Research). The instrument was installed in a dedicated measuring room at the 7th floor of the Lamark B building of Université Paris Cité. Air was taken from a common certified PM1 sampling head located on the roof of the building at about 30 m height above the ground level. A copper tube of 7 mm inner diameter and 10 m length connected the PM1 head to a 4–way stainless steel flow splitter (TSI) located in the measuring room that dispatched the air flow to different instruments. The ACSM sampled air from this common line at a flow rate of 0.085 l min-1 through a nafion dryer. The airflow is then directed to the inlet of an aerodynamic lens that focuses submicron particles into a high-vacuum system. Data were acquired continuously at 6–min time resolution. Multiple zero check were performed during the campaign to evaluate possible offset baseline and instrument noise. Acquisition was done with Acquility v2.3.18 and data traitment by Tofware_V3_2 running under IGOR 7. Data were acquired and are reported here at ambient conditions. The ACSM was calibrated with monodispersed (300 nm) ammonium nitrate and ammonium sulphate particles used to derive NO3 IE (Ionisation Efficiency) and NH4 and SO4 RIE (Relative Ionisation Efficiency). Raw data were controlled manually to check periods when specific conditions prevented to do measurements or affected the quality of the measurements (power cut, zero check, disconnection from the sampling line, disfunctioning). Data in correspondence of these periods are identified as -9999.999 and flagged with a “M” (missing). Valid data are reported with a “O” flag (operation). Different periods were affected by rain on the 19–23, 24–27 and 30 June and 4, 19–20 and 22 July. Detailed information on the rainy periods can be provided upon request to the principal investigators. For the 13 July-18 July period the PM1 head was accidentally disconnected, however data for the ACSM are provided as little transmission of large particles is expected by the aerodynamic lens. A collection efficiency (CE) of 0.5 throughout the campaign is assumed, resulting in less than 10% deviation from the total non-refractory mass estimated from co-located Scanning Mobility Particle Sizer (SMPS) and equivalent black carbon concentration by an aethalometer (AE33) at the site. In regard to the CE, the 25th of June and the 13th–14th of July should be treated with care since not fully neutralized. Data calculated with the Chemical Dependent Collection Efficiency (CDCE) can be provided upon request to the principal investigators. The Limit Of Detection (LOD), calculated as three times the standard deviation of HEPA filter zero checks, are estimated at 0.05, 0.33, 0.08, 0.11, 0.46, and 0.69 µg m–3 for chloride, ammonium, sulphate, nitrate, organic matter and the total mass, respectively. The uncertainties associated to the ACSM total mass concentration is around 25% based on Budisulistiorini et al. (2014). Additional products retrieved from ACSM data, such as the aerosol time–dependent aerosol density, the organic nitrate, the oxygen–to–carbon and hydrogen–to–carbon ratios, and the hydrocarbon-like (HOA) and oxygenated-like (OOA) organic aerosols can be provided upon request to the principal investigators.