Supplementary material to "A searchable database and mass spectral comparison tool for aerosol mass spectrometry (AMS) and aerosol chemical speciation monitor (ACSM)"

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S1. Description of comparison constraints provided by the panel1. Sample type: This indicates if there were any instrumental or experimental setup conditions that are not reflective of general atmospheric conditions.Sample type is classified into 'Ambient' (immediate ingestion of ambient air to the instrument) and 'Non-ambient' (including all chamber studies, any measurement whereby the spectrum is a specific source or a standard, collected on filters as a preliminary step).2. Perturbation: This indicates if there was a perturbation of the sample due to some instrumental intermediary.If the sampling was carried out with an oxidation flow reactor, a thermodenuder, or if a sample was collected on filters, for example, it is classified as 'Perturbed', if not, 'Non-Perturbed'.3. Deconvoluted: This denotes if the spectrum was generated by an analysis step such as positive matrix factorization (PMF).If yes, then 'Deconvoluted', if not, then 'Non-deconvoluted' 4. Instrument: This indicates the instrument used for detection.It includes Air Quality ACSM, ToF-ACSM, Quad-AMS, C-ToF-AMS, HR-ToF V-mode, HR-TOF W-mode, Long-ToF V-mode, Long-ToF W-mode, and multiple instruments.5. Resolution: This indicates the resolution of the sample spectrum.Options are UMR (unit mass resolution), HR to UMR (high resolution converted to UMR), and combination (HR for low masses, UMR for high).6. Vaporizer type: The two options are a capture vaporizer and a standard vaporizer.7. Aerosol CO and CO2 contributions: This indicates whether the signals of CO + at m/z 28 and CO2+ at m/z 44 in the mass spectrum were adjusted to be equal during the data processing.In the case of UMR data, the default signal from aerosol CO + at m/z 28 is set to be identical to the contribution from aerosol CO2 + signal at m/z 44 (Allan et al., 2004).Especially in the case of high biomass burning sources, users may have adjusted the organic component at m/z 28 to be different from that at CO2 at m/z 44.In the UMR case ('mz 28/mz 44 = 1 (for UMR)' on the UMR comparison tab of the panel), this option screens for cases when these two signals are equal, which is reflective of more ambient measurements and the default fragmentation table, and for cases when these signals are not equal ('Ratio ≠ 1 (for both)' on the UMR comparison tab), which is very uncommon.In the case of HR data, the default setting is to not fit the CO + ion, as it is generally unseparated from the dominant N2 + ion at m/z 28.The default setting in the HR fragmentation table is to set the signal of aerosol CO + to aerosol CO2 + .In terms of HR families, this default setting means that the family CHO1 signal at m/z 28 is equal to the family CHOgt1 signal at m/z 44.In the HR case ('CO (CHO1) / CO2 (CHOgt1) = 1 (for HRtoUMR)' on the UMR comparison tab or 'CO/CO2 =1' on the HR comparison tab of the panel), this option screens for cases when these two signals are equal, which is reflective of more ambient measurements and the default HR fragmentation table, and for cases when these signals are not equal ('CO/CO2 ≠ 1' on the HR comparison tab of the panel), which is very uncommon.Table S1.Description of the chemical formula for HR family name.HR family name Chemical formula Cx Cx CH CxHy CHO1 CxHyOz (z=1) CHOgt1 CxHyOz (z>1) CHN CxHyNw CHO1N CxHyOzNw (z=1) CHOgt1N CxHyOzNw (z>1) CS CxSy HO HxOy Air* Nx, Ox, Ar Cl HxCly NH NxHy SO SxOy NO NxOy Tungsten* WxOy (y≥0) Other All ions not included in any other category CSi CxSiy *On the HR comparison tab, air and tungsten abundances are reset to zero.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.