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Updated: Jun 3, 2026

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
Published on: February 10, 2020
Responsivity-based criterion for accurate calibration of FTIR emission spectra: theoretical development and bandwidth
Penny M Rowe1, Steven P Neshyba, Von P Walden
1Department of Geography, University of Idaho, 875 Perimeter Drive, Moscow, Idaho 83844, USA. prowe@harbornet.com
Abstract:
An analytical expression for the variance of the radiance measured by Fourier-transform infrared (FTIR) emission spectrometers exists only in the limit of low noise. Outside this limit, the variance needs to be calculated numerically. In addition, a criterion for low noise is needed to identify properly calibrated radiances and optimize the instrument bandwidth. In this work, the variance and the magnitude of a noise-dependent spectral bias are calculated as a function of the system responsivity (r) and the noise level in its estimate (σr). The criterion σr/r<0.3, applied to downwelling and upwelling FTIR emission spectra, shows that the instrument bandwidth is specified properly for one instrument but needs to be restricted for another.
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