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Capabilities / Instruments

CAPS-PMEX

Cavity Attenuated Phase Shift Extinction Monitor

Baseline Instrument

The cavity attenuated phase shift extinction monitor is an optical extinction spectrometer that measures aerosols, broadband scatterers and absorbers of light that interact with solar radiation and influence the Earth’s radiation balance. The CAPS PM_ex uses a visible-light-emitting diode (LED), a sampling cell incorporating two high-reflectivity mirrors centered at the wavelength of the LED, and a vacuum photodiode detector.

Primary Measurements

Aerosol extinction

Handbook Browse Data

Contact

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Arthur Sedlacek
Lead Mentor Brookhaven National Laboratory

Related Data Announcements

Aerosol Optical Properties VAP Now Available

References

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Mayol-Bracero et al. ARM FY2026 Aerosol Operations Plan. 2026. 10.2172/2997144.
Sedlacek et al. Cavity Attenuated Phase Shift Monitor Instrument Handbook. 2025.

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Resources

Atmospheric Radiation Measurement (ARM) | Reviewed March 2025