Two Planets Straddling the Habitable Zone of The Nearby K Dwarf Gl 414A

TL;DR

This paper reports the discovery of two planets orbiting the nearby K7 dwarf Gl 414A, with detailed analysis of radial velocity and photometric data revealing their properties and stellar activity signals, highlighting a potential target for direct imaging.

Contribution

First detection and characterization of two planets around Gl 414A using combined radial velocity and photometric data, including analysis of stellar activity signals.

Findings

Gl 414A b is a sub-Neptune with ~9.3 Earth masses at 0.24 au.

Gl 414A c is a sub-Saturn with ~59.5 Earth masses at 1.43 au.

Outer planet may be suitable for future direct imaging.

Abstract

We present the discovery of two planets orbiting the nearby (D=11.9 pc) K7 dwarf Gl 414A. Gl 414A b is a sub-Neptune mass planet with M$_b \sin{i_b} = 9.28^{+3.19}_{-2.54}$ M$_\oplus$ and a semi-major axis of 0.24 $\pm$ 0.01 au. Gl 414A c is a sub-Saturn mass planet with $M_c \sin{i_c} = 59.48^{+9.98}_{-9.69}$ M$_\oplus$ and a semi-major axis of 1.43 $\pm$ 0.06 au. We jointly analyzed radial velocity data from Keck/HIRES and the Automated Planet Finder at Lick Observatory, as well as photometric data from KELT, to detect the two planets as well as two additional signals related to the rotationally-modulated activity and the long term magnetic activity cycle of the star. The outer planet in this system may be a potential candidate for future direct imaging missions.