# New substellar discoveries from Kepler and K2: Is there a brown dwarf desert?

## TL;DR

This paper reports new brown dwarf and low mass star discoveries from Kepler and K2, analyzing their properties and implications for the brown dwarf desert, including revisiting a previously known brown dwarf in a star cluster.

## Contribution

It presents new measurements of two substellar objects, providing insights into the brown dwarf desert and revisiting a previously known brown dwarf with improved data.

## Key findings

- EPIC 212036875b is in the brown dwarf desert region.
- CWW 89Ab is a transiting brown dwarf in a star cluster.
- The brown dwarf desert may not be as dry as previously thought.

## Abstract

We present the discoveries of a brown dwarf and a low mass star from the Kepler and K2 missions. The newly discovered brown dwarf is EPIC 212036875b and the low mass star is KOI-607b. EPIC 212036875b has a mass of $ M_{b}=52.3\pm 1.9M_J$, a radius of $ R_{b}=0.874\pm 0.017R_J$, and orbits its host star in $ P=5.169885 \pm 0.000027$ days. Its host star is a late F-type star with $ M_\star=1.288\pm 0.065M_\odot$, $ R_\star=1.498\pm 0.025R_\odot$, and $ T_{\rm eff}=6238 \pm 60$K. KOI-607b has a mass of $ M_{b}=95.1\pm 3.4M_J$, a radius of $ R_{b}=1.089\pm 0.089R_J$, and an orbital period of $ P=5.89399148 \pm 0.00000060$ days. The primary star in the KOI-607 system is a G dwarf with $ M_\star=0.993\pm 0.052M_\odot$, $ R_\star=0.915\pm 0.031R_\odot$, and $ T_{\rm eff} = 5418\pm 87$K. We also revisit a brown dwarf, CWW 89Ab, that was previously published by Nowak et al. 2017 (under the designation EPIC 219388192b). CWW 89Ab is one of two known transiting brown dwarfs associated with a star cluster, which illustrates the need for more brown dwarfs with accurate masses and radii and reliable age determinations to test theoretical models. We find that the newly discovered brown dwarf, EPIC 212036875b, falls in the middle of the so-called "brown dwarf desert", indicating that EPIC 212036875b is either a particularly rare object, or the brown dwarf desert may not be so dry after all.