A Principal Component Analysis-based method to analyse high-resolution spectroscopic data

M. Damiano; G. Micela; G. Tinetti

doi:10.3847/1538-4357/ab22b2

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arXiv · 1906.11218

A Principal Component Analysis-based method to analyse high-resolution spectroscopic data

M. Damiano·G. Micela·G. Tinetti

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Abstract

High-Resolution Spectroscopy (HRS) has been used to study the composition and dynamics of exoplanetary atmospheres. In particular, the spectrometer CRIRES installed on the ESO-VLT has been used to record high-resolution spectra in the Near-IR of gaseous exoplanets. Here we present a new automatic pipeline to analyze CRIRES data-sets. Said pipeline is based on a novel use of Principal Component Analysis (PCA) and Cross-Correlation Function (CCF). The exoplanetary atmosphere is modeled with the $\tau$-REx code using opacities at high temperature from the ExoMol project. In this work, we tested our analysis tools on the detection of CO and H$_2$O in the atmospheres of the hot-Jupiters HD209458b and HD189733b. The results of our pipeline are in agreement with previous results in the literature and other techniques.

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M. Damiano, G. Micela, G. Tinetti. 2019-06-26. A Principal Component Analysis-based method to analyse high-resolution spectroscopic data. https://doi.org/10.3847/1538-4357%2Fab22b2

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