FAQ AMS Glossary

AMS glossary (beta)

Important Notes

This glossary of terms typically used by the AMS community is a work in progress - so is by no means complete or comprehensive. For now, we'll keep it alphabetical, but this may be changed based on user feed-back. Please continue to add and edit!

Glossary

AMS: Aerosol Mass Spectrometer

APES:

BBOA: Biomass Burning Organic Aerosol

Closed: The mass spectrum taken with the chopper in the 'blocked' position, and typically considered instrument background and gas-phase contribution to AMS signal

CRiTTR

DAQ: Data Acquisition Software

Diff: The Difference Spectrum; difference in chopper-open mass spectrum and chopper-closed mass spectrum; typically considered the mass spectrum due to particle signal

f_44: the fraction of the organic signal that is observed at m/z = 44

fragments: a vaporized molecule is ionized in the AMS to a series of ions, which are then detected by either a quadrupole or time-of-flight mass spectrometer; the resulting ions are referred to as 'fragments'

HOA: Hydrocarbon-like Organic Aerosol

HR: High Resolution (as opposed to UMR, typically referring to either the High Resolution Time of Flight Aerosol Mass Spectrometer, or to the data derived from that instrument)

Light Scattering:

Non-refractory species: chemical components of aerosol that are volatilized in the AMS, and are observed in the "Difference spectrum". Examples include...

OOA: Oxidized Organic Aerosol

Open:

PIKA:

Q:

Refractory species: chemical components of aerosol that are not volatile enough to vaporize in the AMS, and thus are never observed by the instrument. Examples include black carbon (see SP2-AMS).

Semi-refractory signals: chemical components of aerosol that are relatively less volatile, and only slowly vaporize in the AMS. Functionally, they are observed in both the the Closed and Open signals (time-scale for vaporization is slow). Examples include Pb (lead) and possibly NaCl

SP2-AMS:

SQUIRREL:

ToF: Time of Flight mass spectrometer

UMR: Unit Mass Resolution (as opposed to HR: ie, signal observed at m/z 28 is UMR, whereas HR data typically shows two peaks, one from N2+ and another from CO+)