A New Probe of Dark Matter and High-Energy Universe Using Microlensing

Understand

We propose the existence of ultracompact minihalos as a new type of massive compact halo object (MACHO) and suggest an observational test to discover them.

• These new MACHOs are a powerful probe into the nature of dark matter and physics in the high energy Universe.
• Non-Gaussian energy-density fluctuations produced at phase transitions (e.g., QCD) or by features in the inflaton potential can trigger primordial black hole (PBH) formation if their amplitudes are delta > 30%.
• We show that a PBH accumulates over time a sufficiently massive and compact minihalo to be able to modify or dominate its microlensing magnification light curve.