Diluted Axion Star Collisions with Neutron Stars

Understand

Diluted axion star, a self-gravitating object with the quantum pressure balancing gravity, has been predicted in many models with a QCD axion or axion-like particle.

• It can be formed in the early universe and composes a sizable fraction of dark matter.
• One could detect the transient radio signals when it passes by a magnetar with the axion particle converted into photon in the magnetic field.
• Using both numerical and semi-analytic approaches, we simulate the axion star's dynamic evolution and estimate the fraction of axion particles that can have a resonance conversion during such a collision event.