Ascertain the theoretical outcomes of stellar mergers and the properties of merger remnants

Ascertain the physical outcomes of stellar mergers in young multiple-star systems, including the resulting remnant’s composition, structure, rotation, and subsequent evolution, and develop models that reliably predict these outcomes across varying progenitor masses and merger histories.

Background

The simulation reveals that mergers are common, especially in massive systems, and can contribute substantially to stellar mass growth. However, accurately modelling post-merger remnants is difficult due to the sporadic and repeated nature of events and the diversity of progenitor masses.

The authors connect merger outcomes to broader astrophysical implications (e.g., magnetic massive stars, mass function shaping), explicitly noting that these theoretical outcomes remain insufficiently understood, underscoring the need for improved modelling and interpretation.