Light-curve analysis of KOI 2700b: the second extrasolar planet with a comet-like tail

TL;DR

This study models the light curve of KOI 2700b, confirming its disintegrating-planet nature and characterizing its comet-like tail using radiative transfer simulations, thus providing insights into its physical properties.

Contribution

It presents the first detailed light-curve modeling of KOI 2700b, confirming its disintegrating-planet scenario and constraining tail and planet characteristics.

Findings

Confirmed disintegrating-planet scenario for KOI 2700b

Derived properties of the comet-like tail

Modeled dust and tail structure using SHELLSPEC

Abstract

The Kepler object KOI 2700b (KIC 8639908b) was discovered recently as the second exoplanet with a comet-like tail. It exhibits a distinctly asymmetric transit profile, likely indicative of the emission of dusty effluents and reminiscent of KIC 12557548b, the first exoplanet with a comet-like tail.The scientific goal of this work is to verify the disintegrating-planet scenario of KOI 2700b by modeling its light curve and to put constraints on various tail and planet properties, as was done in the case of KIC 12557548b. We obtained the phase-folded and binned transit light curve of KOI 2700b, which we subsequently iteratively modeled using the radiative-transfer code SHELLSPEC. We modeled the comet-like tail as part of a ring around the parent star and we also included the solid body of the planet in the model. During the modeling we applied selected species and dust particle sizes. We confirmed the disintegrating-planet scenario of KOI 2700b. Furthermore, via modeling, we derived some interesting features of KOI 2700b and its comet-like tail.