Calibration of a photoacoustic spectrometer cell using light absorbing aerosols. A technical note
Nir Bluvshtein1, J. Michel Flores1, Quanfu He1, Enrico Segre2, Lior Segev1, Nina Hong3, Andrea Donohue3, James N. Hilfiker3, and Yinon Rudich11Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel 2Physical services, Weizmann Institute of Science, Rehovot 76100, Israel 3J.A. Woollam Co., Inc., 645 M Street, Suite 102 Lincoln, NE 68508, USA
Received: 29 Sep 2016 – Accepted for review: 08 Nov 2016 – Discussion started: 08 Nov 2016
Abstract. Multi-pass photoacoustic spectrometer (PAS) is an important tool for the direct measurement of light absorption by atmospheric aerosol. And accurate PAS measurements require an accurate calibration of its signal. Ozone is often used for calibrating the PAS by relating the instrument signal to the absorption coefficient measured by an independent method such as cavity ring down spectroscopy (CRD), cavity enhanced spectroscopy (CES) or an ozone monitor. We report here a calibration method that uses measured absorption coefficients of aerosolized, light absorbing organic materials and offer an alternative approach to calibrate the PAS at 404 nm. To implement this method we first determined the complex refractive index of an organic dye using spectroscopic ellipsometry, and then we use this well characterized material as a standard material for PAS calibration.
Bluvshtein, N., Flores, J. M., He, Q., Segre, E., Segev, L., Hong, N., Donohue, A., Hilfiker, J. N., and Rudich, Y.: Calibration of a photoacoustic spectrometer cell using light absorbing aerosols. A technical note, Atmos. Meas. Tech. Discuss., doi:10.5194/amt-2016-323, in review, 2016.