UNIVERSITÉ D'ORLÉANS - Laboratoire de physique et chimie de l ...

Fig. 1. Retrieval of HCl near 2925.9 cm -1 from spectra obtained on 10 June 2008 at 12.08 hPa
(~29.87 km). The signal is the average of 3 consecutive spectra over 3.3 s. The optical path
length is 430.78 m. Top: Experimental transmission (black curve) with the retrieval of the
baseline and synthetic spectrum (red curve); Middle: Second derivative of the synthetic and
experimental spectra; Bottom: Residual of the direct absorption signal (pink line) and of the
second derivative signal (blue line). Statistical precision on the fit is 1.6 % (2σ).
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