The Quadrupole Aerosol Mass Spectrometer (Q-AMS) is an instrument for the real-time measurement of size-resolved aerosol chemical composition. The Q-AMS is built by Aerodyne Research, and was developed by Aerodyne in collaboration with several university research groups, including the Jimenez Group at the University of Colorado and the Coe Group at the University of Manchester. The ToF-AMS is a newer instrument, which differs from the Q-AMS in the replacement of the quadrupole mass filter with a custom designed Tofwerk time-of-flight mass Spectrometer.

Note that this page is different from the Aerosol Mass Spectrometry Web Page, which compiles information on many types of aerosol mass spectrometry instruments besides the AMS, and from the ToF-AMS web page. One way to distinguish the pages is by the three different instrument schematics at the top each one.

Resources and Information on the Q-AMS

Q-AMS Software

• Data Acquisition Software for the Q-AMS
• Data Analysis Software ("James' Program")
• Beam Width Probe Software

Q-AMS Manuals and Hardware Information

• Manuals
  • Q-AMS Manual (version 3.2 from Sep. 2002, covers both software and hardware)
  • Q-AMS Manual (Newer version, but only covers hardware)
  
  
• General Information
  • AMS Specifications (Dec. 2000)
  • AMS Setting Summary Sheets. These contain a user-modifiable summary of various settings of the AMS (pump speeds and currents, Balzers settings, electronics settings), to be printed and pasted on the instrument.
  • Agenda for AMS Training Course
  
  
• Vacuum System
  • AMS Vacuum Failure Plan (by Ed Dunlea at CU, in xls)
  • AMS Vacuum System Start-Up Procedure
  
  
• Multiplier and Detection System
  • Replacement of ETP Electron Multiplier
  • AMS Electronic Noise Reduction
  
  
• Chopper and Servo
  • Pinout of the Chopper Connector
  • How to Measure Chopper Signals (for diagnosing problems)
  • Replacement of Chopper Servo
  • Chopper Circuit Board Diagram
  
  
• Manuals and Settings for the Balzers Quadrupole Mass Spectrometer
• Typical Balzers Ionizer Voltages
• Settings of the Balzers Controller for AMS Purposes (JL Jimenez & R Bahreini's during ACE-Asia, April 2001)
• Control Unit (QMG 422)
• Mass Analyzer (QMA 400)
• Serial Communication Protocols


• Manuals for the Varian Turbo Pumps and Controllers
• V70LP Turbo Pump
• PCB Controller for V70 Turbo Pump (969-9515, "old style")
• PCB Controller for V70 Turbo Pump (969-9518, "new style")
• V250 Turbo Pump
• PCB Controller for V250 Turbo Pump
• V301 Turbo Pump
• Software to Toggle a V70 Varian Pump Controller between V70 and V250/V301 operation. This allows one to use a V70 controller, rather than a V250 or V301 controller, to run a V250 or V301 pump. The controller starts more slowly and is more patient to let the pump reach full speed. W/o this modification, the larger pumps draw too much power and shut down. Note that this will only work for a V250 or V301 w/o high gas load.


• Manuals for the National Instruments Data Acquisition Hardware and Software
  • Noise and Wiring Considerations for Analog Signals
  • Understanding Amplifier Settling Time
  • Data Acquisition Fundamentals
  • Data Acquisition Glossary
  • NI Data Acquisition Hardware Overview
  • PCI-6110E board ("fast")
  • Specification corrections for the PCI-6110E board
  • PCI-6024E board ("slow")
  • PCI-6703 board ("output")
  • PCI E Series Boards Manual
  • BNC-2090 Connector Manual
  • SCB-68 Connector Manual
  • Information for Q-AMS DAQ Software Programming
    • NIDAQ User Manual
    • NIDAQ Reference Manual
    • Fundamentals of Direct Memory Access (DMA) Programming

Other Reference Materials

• Publications using the AMS (both Q and ToF)
• Canagaratna et al., Review Paper on the AMS: "Chemical and Microphysical Characterization of Ambient Aerosols with the Aerodyne Aerosol Mass Spectrometer". Mass Spectrometry Reviews, in press, April 2006. PDF of accepted version and Figures
• Aerodyne AMS Users Meetings
• AMS operation worksheets developed by J.L. Jimenez. The purpose of these sheets is to avoid preventable mistakes in the operation of the AMS, especially by new users, and to systematize the recording of information (so that it can be easily retrieved long after the experiment by someone not taking part on it). This is the latest version for the CELTIC field campaign (July 2003). Other users should can modify them for their own purposes.
• Email lists for AMS Users
• Example VB5 program to manipulate ITX datafiles, developed by Jose to fix a problem with the Pittsburgh dataset. This can be useful when you want to make small changes to your ITX files, so that they are interpreted properly by the data analysis software.
• NIST Database of Electron Impact Ionization Cross Sections
• NIST Chemistry Webbook. This webbook includes EI spectra of ~6,000 molecules. The complete NIST database contains EI spectra of nearly 200,000 molecules, and can be purchased for ~$3,000.

Q-AMS Pictures

• The prototype AMS at Aerodyne (1997)
• The first field-deployable AMS during the Atlanta Supersite (1999)
• The Caltech AMS vacuum chamber and detector: side, front, and back
• The Caltech AMS during ACE-Asia (2001): front, back, top
• The Caltech AMS inside the Twin Otter Aircraft
• The Caltech AMS in the Roof Lab (2002)
• Two-Piece AMS (used for all early commercial instruments)