Time dependent mechanical feedback during life and death of populations of binary massive stars
Massive stars strongly impact their environment, shaping structures on all scales throughout the universe and impacting subsequent generations of star formation, in a process known as feedback. Since most massive stars form in binary systems, it is crucial to understand how binary interactions modify the feedback properties of stellar populations, both before and during their supernova (SN) phase. The energy, momentum, and mass returns—key components in models of galaxy formation and dynamics—are heavily dependent on the evolutionary pathways a binary system may follow and on metallicity. This highlights the importance of studying not only individual stars or binary systems but also how feedback operates collectively across entire stellar populations in galaxies. To address this, we conduct a binary population synthesis study using the next generation POSYDON code, built on high-precision MESA binary models, to quantify the energy, momentum, and mass ejected by stellar populations across a wide range of metallicities and over time. This study accounts for all possible evolutionary channels and incorporates various updated SN prescriptions. Our findings reveal that a significant fraction of stars are able to explode much earlier or later in time through binary interactions compared to a single-star population, significantly altering the SN feedback in high-metallicity environments. At lower metallicities, these interactions delay the timing of pulsational pair-instability and pair-instability SNe, influencing early energetic outputs. Binary systems also greatly enhance pre-SN feedback, increasing the mechanical energy budget and mass loss, particularly at low metallicities. This enhancement is primarily driven by delayed winds from merged products and mass transfer processes. Comparing our results with prior studies, we highlight how binary evolution fundamentally reshapes energy, momentum, timing, and mass yields, profoundly impacting their host galaxies/enviroments
