# EPIC 228735255b - An eccentric 6.57 day transiting hot Jupiter in Virgo

## TL;DR

This paper reports the discovery of EPIC 228735255b, a hot Jupiter with a 6.57-day orbit around a G-type star, detected via K2 photometry and ground observations, notable for its eccentricity and moderate inflation.

## Contribution

First detection of an eccentric hot Jupiter with a period over 6 days using K2 data, demonstrating K2's capability to find longer-period transiting giants.

## Key findings

- Planet has a mass of 1.019 M_Jup and radius of 1.095 R_Jup.
- Orbit is eccentric with e=0.12.
- Host star's rotation period is 16.3 days.

## Abstract

We present the discovery of EPIC 228735255b, a P= 6.57 days Jupiter-mass (M$_P$=1.019$\pm$0.070 M$_{Jup}$) planet transiting a V=12.5 (G5-spectral type) star in an eccentric orbit (e=$0.120^{+0.056}_{-0.046}$) detected using a combination of K2 photometry and ground-based observations. With a radius of 1.095$\pm$0.018R$_{Jup}$ the planet has a bulk density of 0.726$\pm$0.062$\rho_{Jup}$. The host star has a [Fe/H] of 0.12$\pm$0.045, and from the K2 light curve we find a rotation period for the star of 16.3$\pm$0.1 days. This discovery is the 9th hot Jupiter from K2 and highlights K2's ability to detect transiting giant planets at periods slightly longer than traditional, ground-based surveys. This planet is slightly inflated, but much less than others with similar incident fluxes. These are of interest for investigating the inflation mechanism of hot Jupiters.