Master presentation: Konstantinos Topalakis

The Impact of Dark Matter Annihilation on Massive Protostellar Structures

Abstract

In this work, we explore how self-annihilating dark matter can reshape the birth and evolution of primordial Population III.1 stars by incorporating Weakly Interacting Massive Particles (WIMPs) energy injection into a one-dimensional stellar evolution code (GENEC). By systematically varying ambient dark matter density, baryonic accretion rate, WIMP mass, and scattering cross-section, we identify the regimes in which annihilation heating overwhelms both gravitational contraction and nuclear burning, giving rise to bloated dark matter powered protostars that bypass the classical zero-age main-sequence. We show that only under sufficiently high dark matter densities does collapse stall, inflating the protostar onto a cool, Hayashi-like track and suppressing its thermonuclear ignition for up to 100,000 years, during which it can accrete to supermassive scales. These Pop III.1 protostars—appearing as cool, infrared-bright supergiants at high redshift—offer a viable pathway to seeding the supermassive black holes observed in the early universe.

Student: Konstantinos Topalakis

Supervisor: Prof. Jonathan Tan

Co-Supervisor: Dr. Devesh Nandal

Examiner: Prof. Maria Sundin

Opponent: Ioannis Moutsis