A Gaussian process framework for modelling instrumental systematics: application to transmission spectroscopy

2011/09/28 by N. P. Gibson, Neale P. Gibson, S. Aigrain +6 · 10 citations
Chemistry · Physics and Astronomy · #Algorithm #Artificial intelligence #Astronomy #Astronomy and Astrophysical Research #Computer science #Gaussian #Gaussian process #Noise (video) #Parametric statistics #Physics #Spectroscopy #Spectroscopy and Chemometric Analyses #Statistical physics #Statistics #Stellar, planetary, and galactic studies #astro-ph.EP

paper · pdf · doi:10.1111/j.1365-2966.2011.19915.x

6 figures, 1 table, accepted for publication in MNRAS

arxiv created 2011/09/28 · openalex publication_date 2011/11/17 · arxiv updated 2015/05/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

Transmission spectroscopy, which consists of measuring the wavelength-dependent absorption of starlight by a planet’s atmosphere during a transit, is a powerful probe of atmospheric composition. However, the expected signal is typically orders of magnitude smaller than instrumental systematics and the results are crucially dependent on the treatment of the latter. In this paper, we propose a new method to infer transit parameters in the presence of systematic noise using Gaussian processes, a technique widely used in the machine learning community for Bayesian regression and classification problems. Our method makes use of auxiliary information about the state of the instrument, but does so in a non-parametric manner, without imposing a specific dependence of the systematics on the instrumental parameters, and naturally allows for the correlated nature of the noise. We give an example application of the method to archival NICMOS transmission spectroscopy of the hot Jupiter HD 189733, which goes some way towards reconciling the controversy surrounding this data set in the literature. Finally, we provide an appendix giving a general introduction to Gaussian processes for regression, in order to encourage their application to a wider range of problems.

Citations

• The Transit Light Curve Project. IX. Evidence for a Smaller Radius of the Exoplanet XO‐3b
• Detection of an Extrasolar Planet Atmosphere
• The Transit Light Curve Project. I. Four Consecutive Transits of the Exoplanet XO‐1b
• PARAMETER ESTIMATION FROM TIME-SERIES DATA WITH CORRELATED ERRORS: A WAVELET-BASED METHOD AND ITS APPLICATION TO TRANSIT LIGHT CURVES
• Transit infrared spectroscopy of the hot Neptune around GJ 436 with the Hubble Space Telescope
• Inference from Iterative Simulation Using Multiple Sequences
• Detection of Thermal Emission from an Extrasolar Planet
• Detection of atmospheric haze on an extrasolar planet: the 0.55-1.05 μm transmission spectrum of HD 189733b with the Hubble Space Telescope
• The effect of red noise on planetary transit detection

Cited by

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• ACCESS: A Visual to Near-infrared Spectrum of the Hot Jupiter WASP-43b with Evidence of H2O, but No Evidence of Na or K
• Searching for the Transit of the Earth-mass Exoplanet Proxima Centauri b in Antarctica: Preliminary Result
• DETECTION OF H 2 O AND EVIDENCE FOR TiO/VO IN AN ULTRA-HOT EXOPLANET ATMOSPHERE
• THE DEEP BLUE COLOR OF HD 189733b: ALBEDO MEASUREMENTS WITH HUBBLE SPACE TELESCOPE /SPACE TELESCOPE IMAGING SPECTROGRAPH AT VISIBLE WAVELENGTHS
• A Gemini ground-based transmission spectrum of WASP-29b: a featureless spectrum from 515 to 720 nm
• Applications of a Gaussian Process Framework for Modelling of High-Resolution Exoplanet Spectra
• De-jittering Ariel: an optimized algorithm
• SSSpaNG! Stellar Spectra as Sparse, data-driven, Non-Gaussian processes