Journal Club

Kinetic Misalignment Mechanism [1910.14152]

by Quentin Bonnefoy (DESY)

Thursday, November 28, 2019 from to (Europe/Berlin)
at Building 2, 4th floor ( Library )

Kinetic Misalignment Mechanism

Raymond T. Co, Lawrence J. Hall, Keisuke Harigaya

In the conventional misalignment mechanism, the axion field has a constant initial field value in the early universe and later begins to oscillate. We present an alternative scenario where the axion field has a nonzero initial velocity, allowing an axion decay constant much below the conventional prediction from axion dark matter. This axion velocity can be generated from explicit breaking of the axion shift symmetry in the early universe, which may occur as this symmetry is approximate.