1. ISSAOS 2008 l‘Aquila, September 2008 Aerosol Mass Spectrometry: The Aerosol mass Spectrometer Hugh Coe School of Earth, Atmospheric and Environmental Sciences University of Manchester Reading: D Murphy, The design of single particle laser mass spectrometers, in: Mass Spectrometry Reviews, 2007, 26, 150-165. M. R. Canagaratna et al., Chemical and microphysical characterisation of ambient aerosols with the Aerodyne Aerosol Mass Spectrometer in: Mass Spectrometry Reviews, 2007, 26, 185- 222. H. Coe and J. D. Allan, “Aerosol Mass Spectrometry” in “Atmospheric techniques” ed D. E. Heard, Blackwell Scientific Publishing, 2006 http://cires.colorado.edu/jimenez/ams-papers.html

2. Particle Inlet (1 atm) 100% transmission (30-600 nm), aerodynamic sizing, linear mass signal. Development of an Aerosol Mass Spectrometer for Size and Composition Analysis of Sub-micron Particles. Jayne et al., Aerosol Science and Technology 33:1-2(49-70), 2000. Quadrupole Mass Spectrometer Thermal Vaporization & Electron Impact Ionization Aerodynamic Lens (2 Torr) Chopper Turbo Pump TOF Region Particle Beam Generation Aerodynamic Sizing Particle Composition Aerodyne Aerosol Mass Spectrometer (AMS) http://cires.colorado.edu/jimenez/ams-papers.html

3. AMS Detection Process Oven e-e- Electron Emitting Filament R+R+ Focused Particle Beam Flash Vaporization of Volatiles and Semi-Volatiles 500 C Electron Impact Ionization Universal and quantitative chemical analysis: 0.1  g/m 3 sensitivity. Vaporization and analysis of most aerosol chemical constituents - with primary exception of crustal oxides and elemental carbon. Separation of Vaporization/Ionization allows for Quantitative Measurements

4. Calibration & Experimental Set up…

5. Quantification of Aerosol Mass…(Jimenez et al., 2003) General Formula.. Nitrate Mass loading.. IE Ionisation EfficiencyN A Avogadro’s number Q flow rateI ion rate MW molecular weightC mass concentration

6. Electron Impact a well defined ionisation

7. Quantification of Aerosol Mass… So the Mass loading of component s is.. IE Ionisation EfficiencyN A Avogadro’s number Q flow rateI ion rate MW molecular weightC mass concentration RIE relative ionisation efficiency

8. Quantification of Aerosol Mass… Allan JD, Delia AE, Coe H, Bower KN, Alfarra MR, Jimenez JL, Middlebrook AM, Drewnick F, Onasch TB, Canagaratna MR, Jayne JT, Worsnop DR. 2004b. A generalised method for the extraction of chemically resolved mass spectra from Aerodyne aerosol mass spectrometer data. J Aerosol Sci 35:909–922, doi:910.1016/j.jaerosci. 2004.1002.1007.

9. This is what we measure…… … Alfarra MR, Coe H, Allan JD, Bower KN, Boudries H, Canagaratna MR, Jimenez JL, Jayne JT, Garforth A, Li S-M, Worsnop DR. 2004. CHARACTERIZATION OF AMBIENT AEROSOLS WITH AN AEROSOL MASS SPECTROMETER & Mass Spectrometry Reviews DOI 10.1002/mas 217 Characterization of urban and regional organic aerosols in the lower Fraser Valley using two Aerodyne Aerosol Mass Spectrometers. Atmos Environ 38:5745–5758.

10. Particle Inlet (1 atm) 100% transmission (30-600 nm), aerodynamic sizing, linear mass signal. Development of an Aerosol Mass Spectrometer for Size and Composition Analysis of Sub-micron Particles. Jayne et al., Aerosol Science and Technology 33:1-2(49-70), 2000. Quadrupole Mass Spectrometer Thermal Vaporization & Electron Impact Ionization Aerodynamic Lens (2 Torr) Chopper Turbo Pump TOF Region Particle Beam Generation Aerodynamic Sizing Particle Composition Aerodyne Aerosol Mass Spectrometer (AMS) http://cires.colorado.edu/jimenez/ams-papers.html

11. Particle Velocity Calibration Predicted and Measured Particle Collection Efficiency Aerodynamic Particle Focusing

12. Example of AMS Output Organics Sulphate Nitrate Ammonium

13. Organics Sulphate Nitrate Ammonium Example of AMS Output

14. Organics Sulphate Nitrate Ammonium Example of AMS Output

15. Collection Efficiency (CE) Takegawa, N., Y. Miyazaki, Y. Kondo, Y. Komazaki, T. Miyakawa, J.L. Jimenez, J.T. Jayne, D.R. Worsnop, J. Allan, and R. J. Weber (2005), Characterization of an Aerodyne Aerosol Mass Spectrometer (AMS): Intercomparison with other Aerosol Instruments, Aerosol Science and Technology, 39, 760-770, 2005 Matthew, B.M., T.B. Onasch, and A.M. Middlebrook. Collection Efficiencies in an Aerodyne Aerosol Mass Spectrometer as a Function of Particle Phase for Laboratory Generated Aerosols. Aerosol Science and Technology, In press, July 2008.

16. Quantification of Aerosol Mass… Including the CE, the Mass loading of component s is.. IE Ionisation EfficiencyN A Avogadro’s number Q flow rateI ion rate MW molecular weightC mass concentration RIE relative IECE collection efficiency

17. Understanding Organic Aerosols – Zhang et al., 2005

19. A factor analysis of the time series of organic mass spectra……

20. Extended to Positive Matrix Factorisation (PMF)

22. Data from Gaffney, Marley, Brune, Volkamer, Cardenas et al. Mexico City April 9, 2003 Volkamer, Jimenez, et al., GRL, 2006. Evidence for OOA being a Secondary Photochemical Product

23. Much higher SOA than predicted with current models Discrepancy appears to increase with time Volkamer, Jimenez, et al., GRL, 2006. DeGouw et al. Heald et al. Johnson et al. Increase in SOA with residence time in atmosphere – observations much greater than models

24. A Compact Time of Flight AMS Data from Shane Murphy Caltech

25. A High resolution time of Flight AMS

26. The Ability to resolve atomic composition

28. Ambient aerosol is much more oxygenated than chamber aerosol

29. SP2-AMS schematic Something for the future……

30. Oil Lamp Soot Particles Obtain chemical information on elemental carbon clusters and organic compounds coating the soot cores