Retired A Stars and Their Companions: Eighteen New Jovian Planets

TL;DR

This paper reports the discovery of eighteen new Jovian planets orbiting subgiant stars, significantly expanding the known population of planets around stars more massive than the Sun and providing new insights into such planetary systems.

Contribution

The study presents eighteen newly discovered Jovian planets around subgiant stars, increasing the known sample by 50% for stars over 1.5 solar masses, with detailed observational data.

Findings

Eighteen new Jovian planets discovered.

Planets have masses between 0.9 and 3 Jupiter masses.

Host stars have masses 0.927-1.95 Msun and radii 2.5-8.7 Rsun.

Abstract

We report the detection of eighteen Jovian planets discovered as part of our Doppler survey of subgiant stars at Keck Observatory, with follow-up Doppler and photometric observations made at McDonald and Fairborn Observatories, respectively. The host stars have masses 0.927 < Mstar /Msun < 1.95, radii 2.5 < Rstar/Rsun < 8.7, and metallicities -0.46 < [Fe/H] < +0.30. The planets have minimum masses 0.9 MJup < MP sin i <3 MJup and semima jor axes a > 0.76 AU. These detections represent a 50% increase in the number of planets known to orbit stars more massive than 1.5 Msun and provide valuable additional information about the properties of planets around stars more massive thantheSun.