very robust shot-to-shot normalization of the LIF signal against the light intensity, leading to a much enhanced signal-to-noise ratio. In comparison to a single-pass LIF measurement, CELIF greatly reduces saturation and power broadening due to the much lower photon densities and effectively eliminates stray light due to the transversal mode structure of the cavity.

Section \[sec:experiment\] describes the methodology and how the integrated CRD signal is used for the shot-to-shot normalization of the LIF signal with respect to the fluctuating intensity of a pulsed laser. Absolute absorption coefficients determined from the CRD measurement can then be used to cross calibrate the LIF signal. In this work, CELIF was implemented using a pulsed molecular beam setup and a cell experiment. Section \[sec:results\] presents measurements that scrutinize the methodology, particularly the increased dynamic range. In section \[sec:discussion\], we discuss the characteristics of the method including its enhanced limit of detection and how absolute fluorescence quantum yields can be determined. In the conclusions, we outline the power of the CELIF technique and its most suitable applications.

Experiment {#sec:experiment}
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The fundamental idea of this setup is the combination of CRDS and LIF in a single, pulsed laser beam. A schematic layout of the 