# WASP-167b/KELT-13b: Joint discovery of a hot Jupiter transiting a rapidly-rotating F1V star

## TL;DR

This paper reports the joint discovery of a hot Jupiter transiting a rapidly-rotating F1V star, with a retrograde orbit and stellar pulsations, expanding understanding of planet-star interactions in such systems.

## Contribution

First joint discovery of a hot Jupiter around a rapidly-rotating F1V star with a retrograde orbit and stellar pulsations, highlighting planet-induced stellar variability.

## Key findings

- Planet has a 2.02-day orbit and a radius of 1.5 R_Jup.
- Orbit is retrograde with a sky-projected angle of -165°.
- Host star shows non-radial pulsations, possibly excited by the planet.

## Abstract

We report the joint WASP/KELT discovery of WASP-167b/KELT-13b, a transiting hot Jupiter with a 2.02-d orbit around a $V$ = 10.5, F1V star with [Fe/H] = 0.1 $\pm$ 0.1. The 1.5 R$_{\rm Jup}$ planet was confirmed by Doppler tomography of the stellar line profiles during transit. We place a limit of $<$ 8 M$_{\rm Jup}$ on its mass. The planet is in a retrograde orbit with a sky-projected spin-orbit angle of $\lambda = -165^{\circ} \pm 5^{\circ}$. This is in agreement with the known tendency for orbits around hotter stars to be more likely to be misaligned. WASP-167/KELT-13 is one of the few systems where the stellar rotation period is less than the planetary orbital period. We find evidence of non-radial stellar pulsations in the host star, making it a $\delta$-Scuti or $\gamma$-Dor variable. The similarity to WASP-33, a previously known hot-Jupiter host with pulsations, adds to the suggestion that close-in planets might be able to excite stellar pulsations.