Primordial versus dynamical origin of the declining multiplicity fraction

Determine whether the observed decline in the multiplicity fraction from stars to brown dwarfs and planetary-mass objects is primordial or instead results from dynamical evolution.

Background

The paper notes that the decrease in multiplicity toward lower-mass objects has been established mainly from field populations older than 1 Gyr. Because dynamical interactions can disrupt especially wide, weakly bound brown-dwarf and planetary-mass binaries, the observed field trend may not directly reflect the multiplicity distribution established during formation.

Young associations and star-forming regions provide an opportunity to compare multiplicity across evolutionary stages and environments. Resolving whether the trend is primordial or dynamically produced is therefore important for distinguishing formation mechanisms from subsequent population evolution.