Morphological Lightcurve Distortions due to Finite Integration Time

By David Kipping. 2010

179 citations recorded by the source corpus.

ABSTRACT We explore how finite integration times or equivalently temporal binning inducesmorphological distortions to the transit lightcurve. These distortions, if uncorrectedfor, lead to the retrieval of erroneous system parameters and may even lead to someplanetary candidates being rejected as ostensibly unphysical. We provide analytic ex-pressions for estimating the disturbance to the various lightcurve parameters as afunction of the integration time. These effects are particularly crucial in light of thelong-cadence photometry often used for discovering new exoplanets by for exampleCoRoT and the KeplerMission (8.5 and 30 minutes). One of the dominant effects oflong integration times is a systematic underestimation of the lightcurve derived stellardensity, which has significant ramifications for transit surveys. We present a discussionof numerical integration techniques to compensate for the effects and produce expres-sions to quickly estimate the errors of such techniques, as a function of integrationtime and numerical resolution. This allows for an economic choice of resolution beforeattempting fits of long-cadence lightcurves.Keywords: techniques: photometric — planets and satellites: general — planetarysystems — occultations

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/f9acbaabb913bce46b010b04841a20f4e994a7be

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. D. Charbonneau
2. D. Deming
3. J. Winn
4. C. Dressing
5. Timothy Morton
6. Jon Fortney
7. D. Latham
8. J. Southworth

In Instrumentation

1. D. Charbonneau
2. J. Winn
3. Timothy Morton
4. C. Dressing
5. D. Deming
6. D. Latham
7. C. Moutou
8. P. McCullough

Citations in the corpus

• Optimized transit detection algorithm to search for periodic transits of small planets (2019, background): “(40) in Kipping (2010).”
• THE TRANSITING EXOPLANET SURVEY SATELLITE: SIMULATIONS OF PLANET DETECTIONS AND ASTROPHYSICAL FALSE POSITIVES (2015, methodology): “The effects of time averaging on the uncertainties in transit parameters derived from light-curve fitting have been analyzed by Kipping (2010) and Price & Rogers (2014).”
• PASTIS: Bayesian extrasolar planet validation. I. General framework, models, and performance (2014, methodology): “Note that since the transit signals are injected in the SC data the sampling effects described in, for example, Kipping (2010) are not present here.”
• One of the closest exoplanet pairs to the 3:2 mean motion resonance: K2-19b and c (2015, methodology): “We used an oversampling factor of 10, to account for the finite integration time of the Kepler long-cadence data (Kipping 2010).”