TFAW survey II: Six newly validated planets and 13 planet candidates from K2

Searching for Earth-sized planets in data from Kepler’s extended mission (K2) is a niche that still remains to be fully exploited. The TFAW survey is an ongoing project that aims to re-analyse all light curves in K2 C1–C8 and C12–C18 campaigns with a wavelet-based detrending and denoising method, an...

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Bibliographic Details
Authors: Ser, Daniel del, Fors, Octavi, Alcázar, M. del, Dyachenko, V., Horch, E. P., Tokovinin, Andrei, Ziegler, C., Belle, G. T. van, Clark, C. A., Hartman, Z. D.
Format: article
Status:Published version
Publication Date:2023
Country:España
Institution:Consejo Superior de Investigaciones Científicas (CSIC)
Repository:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/348884
Online Access:http://hdl.handle.net/10261/348884
Access Level:Open access
Keyword:Instrumentation: high angular resolution
Methods: data analysis
Techniques: photometric
Planets and satellites: general
Planets and satellites: terrestrial planets
Description
Summary:Searching for Earth-sized planets in data from Kepler’s extended mission (K2) is a niche that still remains to be fully exploited. The TFAW survey is an ongoing project that aims to re-analyse all light curves in K2 C1–C8 and C12–C18 campaigns with a wavelet-based detrending and denoising method, and the period search algorithm TLS to search for new transit candidates not detected in previous works. We have analysed a first subset of 24 candidate planetary systems around relatively faint host stars (10.9 < Kp < 15.4) to allow for follow-up speckle imaging observations. Using vespa and TRICERATOPS, we statistically validate six candidates orbiting four unique host stars by obtaining false-positive probabilities smaller than 1 per cent with both methods. We also present 13 vetted planet candidates that might benefit from other, more precise follow-up observations. All of these planets are sub-Neptune-sized with two validated planets and three candidates with sub-Earth sizes, and have orbital periods between 0.81 and 23.98 d. Some interesting systems include two ultra-short-period planets, three multiplanetary systems, three sub-Neptunes that appear to be within the small planet Radius Gap, and two validated and one candidate sub-Earths (EPIC 210706310.01, K2-411 b, and K2-413 b) orbiting metal-poor stars.