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arXiv · 1301.4041

Blind extraction of an exoplanetary spectrum through Independent Component Analysis

Ingo P. Waldmann·Giovanna Tinetti·Pieter Deroo·Morgan D. J. Hollis·Sergey N. Yurchenko·Jonathan Tennyson
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Abstract

Blind-source separation techniques are used to extract the transmission spectrum of the hot-Jupiter HD189733b recorded by the Hubble/NICMOS instrument. Such a 'blind' analysis of the data is based on the concept of independent component analysis. The de-trending of Hubble/NICMOS data using the sole assumption that nongaussian systematic noise is statistically independent from the desired light-curve signals is presented. By not assuming any prior, nor auxiliary information but the data themselves, it is shown that spectroscopic errors only about 10 - 30% larger than parametric methods can be obtained for 11 spectral bins with bin sizes of ~0.09 microns. This represents a reasonable trade-off between a higher degree of objectivity for the non-parametric methods and smaller standard errors for the parametric de-trending. Results are discussed in the light of previous analyses published in the literature. The fact that three very different analysis techniques yield comparable spectra is a strong indication of the stability of these results.

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Ingo P. Waldmann, Giovanna Tinetti, Pieter Deroo, Morgan D. J. Hollis, Sergey N. Yurchenko, Jonathan Tennyson. 2013-01-17. Blind extraction of an exoplanetary spectrum through Independent Component Analysis. https://doi.org/10.1088/0004-637x/766/1/7

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