Astrophysics of (Self-Interacting) Ultralight Dark Matter
by
MrHyeonmo Koo(U of Seoul)
→
Asia/Seoul
B447-1
B447-1
Description
Ultralight dark matter (ULDM), composed of spin-zero bosons with extremely small masses, has emerged as a compelling alternative to cold dark matter (CDM) for addressing small-scale challenges of the standard cosmological model. Its wave-like nature gives rise to distinctive astrophysical phenomena on kpc-scales, potentially resolving long-standing issues. However, a synthesis of current astrophysical constraints—from Lyman-α forest observations to dynamical-friction measurements—restricts the viable particle mass to a rather narrow window. This motivates the consideration of a quartic self-interaction term (λφ⁴), which can relax these bounds and enrich the phenomenology of ULDM.
In this talk, I will provide an overview of the astrophysical implications of ULDM across cosmological and galactic scales, including our recent study on the Fornax globular clusters within the self-interacting framework. I will also highlight several open directions that distinguish self-interacting ULDM from the non-interacting case and outline promising avenues for future exploration.