Abstract
Abstract Protostellar core formation and growth in high-mass star-forming regions remain key to understanding massive star birth. We analyze the masses of 839 cores (resolved at scales of a few thousand au) from the ASHES project targeting 39 massive infrared dark cloud clumps. The masses of the three most massive cores scale linearly with the total core mass. They maintain respective constant mass fractions of ∼25%, 16%, and 10% along the mass-growth sequence. These fractions reveal that the progenitor seeds destined to become high-mass cores establish their mass dominance very early. Additionally, the Gini coefficient (a statistical measure of inequality) of the core mass distributions increases along the mass-growth sequence, confirming that the relative population of low-mass cores builds up toward later stages. This points to an environment-dependent fragmentation picture: central prestellar seeds rapidly evolve into high-mass cores via transport-driven super-Jeans fragmentation under rapid, nonstationary mass accumulation in high-density, turbulent hubs, and subsequently maintain their dominance through supply-limited synchronized growth (at R < 1 pc, n H 2 > 1 0 5 cm − 3 ), while the formation of the surrounding low-mass cores is relatively delayed due to their lower gas densities and the lack of nonstationary inflow acceleration effect, resulting in their continuous emergence through Jeans-like fragmentation in lower-density envelopes. This picture is consistent with a gravity-driven scenario where the local freefall time is the controlling factor. Our analysis suggests that nonstationary density-regulated fragmentation and supply-limited accretion jointly drive the synchronized coevolution of the core cluster, seamlessly linking small-scale core growth with large-scale reservoir regulation.