Development of a High Mass Resolution Time of Flight Aerosol Mass Spectrometer

HR: 1340h
AN: A33B-0885 [Abstracts]
TI: Development of a High Mass Resolution Time of Flight Aerosol Mass Spectrometer
AU: * DeCarlo, P F
EM: decarlop@colorado.edu
AF: CIRES, University of Colorado at Boulder, 216 UCB, Boulder, CO 80309 United States
AU: * DeCarlo, P F
EM: decarlop@colorado.edu
AF: Program in Atmospheric Science, University of Colorado at Boulder, 311 UCB, Boulder, CO 80309 United States
AU: Aiken, A C
EM: allison.aiken@colorado.edu
AF: CIRES, University of Colorado at Boulder, 216 UCB, Boulder, CO 80309 United States
AU: Aiken, A C
EM: allison.aiken@colorado.edu
AF: Dept of Chemistry and Biochemistry, University of Colorado at Boulder, 215 UCB, Boulder, 80309 United States
AU: Kimmel, J R
EM: jkimmel@colorado.edu
AF: CIRES, University of Colorado at Boulder, 216 UCB, Boulder, CO 80309 United States
AU: Northway, M
EM: mnorthway@aerodyne.com
AF: Aerodyne Research Inc., 45 Manning Rd, Billerica, MA 01821 United States
AU: Trimborn, A
EM: trimborn@aerodyne.com
AF: Aerodyne Research Inc., 45 Manning Rd, Billerica, MA 01821 United States
AU: Gonin, M
EM: gonin@tofwerk.com
AF: Tofwerk AG, Feuerwerkerstrasse 39, Thun, CH-3602 Switzerland
AU: Furher, K
EM: katrin.fuhrer@bluewin.ch
AF: Tofwerk AG, Feuerwerkerstrasse 39, Thun, CH-3602 Switzerland
AU: Horvath, T
EM: horvath@tofwerk.com
AF: Tofwerk AG, Feuerwerkerstrasse 39, Thun, CH-3602 Switzerland
AU: Jayne, J
EM: jayne@aerodyne.com
AF: Aerodyne Research Inc., 45 Manning Rd, Billerica, MA 01821 United States
AU: Worsnop, D
EM: worsnop@aerodyne.com
AF: Aerodyne Research Inc., 45 Manning Rd, Billerica, MA 01821 United States
AU: Jimenez, J
EM: jose.jimenez@colorado.edu
AF: CIRES, University of Colorado at Boulder, 216 UCB, Boulder, CO 80309 United States
AU: Jimenez, J
EM: jose.jimenez@colorado.edu
AF: Dept of Chemistry and Biochemistry, University of Colorado at Boulder, 215 UCB, Boulder, 80309 United States
AB: A high mass resolution aerosol mass spectrometer has been developed based on the Aerodyne Aerosol Mass Spectrometer Design (AMS). The utilization of a time-of-flight mass analyzer with maximum mass resolution of approximately 5000, allows for the separation of fragments with very small mass differences, but the same nominal mass. As the mass resolution of the instrument increases more peaks are resolved in the mass spectrum of ambient aerosol. For example at mass to charge 43, it is possible to clearly separate the signal of the alkyl fragment (C₃H_{7}⁺) from that of the oxygenated and nitrogenated ones.
(CHNO⁺ and C₂H₃O⁺). The collection of different chemical fragments can be organized into categories such
as fragments containing only carbon and hydrogen atoms (C_xH_y) or ones containing carbon hydrogen and oxygen
(C_xH_yO_z) etc. From this classification relative signal in the different categories can be computed and
intercompared.
This presentation will include a description and characterization of the instrument, and methods for extracting the
information content of the high resolution mass spectra which can be used to determine concentrations of different types of
chemical species in the aerosol. In addition, metrics such as carbon to oxygen ratio for the organic aerosol mass fragments
are easily calculated and can provide insight into degree of atmospheric processing or possible sources and classification of
organic aerosol. Data for pure species calibration particles and ambient aerosol will be presented.} DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0365 Troposphere: composition and chemistry
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005