Simulated mass measurements of the young planet K2-33b

Abstract

In this paper, we carry out simulations of radial velocity (RV) measurements of the mass of the 8-11 Myr Neptune-sized planet K2-33b using high-precision near infrared velocimeters like SPIRou at the Canada-France-Hawaii Telescope. We generate a RV curve containing a planet signature and a realistic stellar activity signal, computed for a central wavelength of 1.8 $\mu$m and statistically compatible with the light-curve obtained with K2. The modelled activity signal includes the effect of time-evolving dark and bright surface features hosting a 2 kG radial magnetic field, resulting in a RV signal of semi-amplitude ~30 m/s. Assuming a 3-month visibility window, we build RV time-series including Gaussian white noise from which we retrieve the planet mass while filtering the stellar activity signal using Gaussian Process Regression. We find that 35/50 visits spread over 3 consecutive bright-time runs on K2-33 allow one to reliably detect planet RV signatures of respectively 10 and 5 m/s at precisions larger than 3 $\sigma$. We also show that 30 visits may end up being insufficient in some cases to provide a good coverage of the stellar rotation cycle, with the result that the planet signature can go undetected or the mass estimation be plagued by large errors.

Letter accepted in MNRAS, 6 pages, 3 figures

References in corpus (7)

• The K2 Mission: Characterization and Early results
• Planets and Stellar Activity: Hide and Seek in the CoRoT-7 system
• EVEREST: Pixel Level Decorrelation of K2 Light curves
• PASTIS: Bayesian extrasolar planet validation. I. General framework, models, and performance
• Four newborn planets transiting the young solar analog V1298 Tau
• A hot Jupiter around the very active weak-line T Tauri star TAP 26
• Simulating Radial Velocity Observations of Trappist-1 with SPIRou

Cited by in corpus (7)

• SPIRou: nIR velocimetry & spectropolarimetry at the CFHT
• Investigating the young AU~Mic system with SPIRou: large-scale stellar magnetic field and close-in planet mass
• The Habitable-zone Planet Finder Reveals A High Mass and a Low Obliquity for the Young Neptune K2-25b
• A 38 Million Year Old Neptune-Sized Planet in the Kepler Field
• The T Tauri star V410 Tau in the eyes of SPIRou and TESS
• Optical and near-infrared stellar activity characterization of the early M dwarf Gl~205 with SOPHIE and SPIRou
• True spin-orbit obliquities distribution: data-driven confirmation of no clustering of misaligned planets