Speaker
Prof.
Yang Qiaoli
Description
The QCD axion cosmological abundance is usually attributed to the misalignment mechanism. We will present a complementary production channel that arises during the QCD phase transition. Primordial temperature fluctuations modulate the axion mass and can trigger parametric resonance in the axion field evolution, exciting finite-momentum modes and enhancing axion production. This effect can significantly modify the predicted axion relic abundance and shift the preferred dark-matter mass range, with implications for ongoing and future axion search experiments.
