Why Wide Jupiter-Mass Binary-Objects Cannot Form

TL;DR

This paper investigates the formation mechanisms of Jupiter-mass binary objects in clusters, highlighting the limitations of current models and emphasizing the need for alternative explanations or further observational confirmation.

Contribution

The study critically examines existing formation theories for JuMBOs, demonstrating their inadequacy in clustered environments and suggesting the necessity for new models or additional data.

Findings

Current models cannot explain JuMBO formation in clusters

Close encounter stripping accounts for only half of observed JuMBOs

Alternative formation mechanisms are likely required

Abstract

The discovery of $N_{\rm pp} = 40$ Jupiter-mass binary objects (JuMBOs) alongside $N_{\rm p} = 500$ free-floating Jupiter-mass objects (JMOs) in the Trapezium cluster's central portion raises questions about their origin \cite{2023arXiv231001231P}. \citet{2024NatAs...8..756W} argue that the rate at which two planets orbiting the same star are stripped by a close encounter can explain about half the observed JuMBOs in the Trapezium cluster. Although, their cross-section calculations agree with our own \citep{2024ScPA....3....1P}, one cannot extrapolate their results into clustered environments because it ignores the dissociation of JuMBOs due to subsequent encounters in the clustered environment. The inability of forming JuMBOs via the proposed scenario either calls for another formation mechanism, or the observed JuMBOs require thorough confirmation.