Speaker
Prof.
Jason Evans
(Korean Institute for Advanced Study)
Description
We present a supersymmetric version of a two-field relaxion model that natu-
ralizes tuned versions of supersymmetry. This arises from a relaxion mechanism
that does not depend on QCD dynamics and where the relaxion potential barrier
height is controlled by a second axion-like eld. During the cosmological evolution,
this allows the relaxion to roll with a nonzero value that breaks supersymmetry
and scans the soft supersymmetric mass terms. Electroweak symmetry is broken
after the soft masses become of order the supersymmetric mass scale, causing the
relaxion to stop rolling at values corresponding to superpartner mass scales up to
~10^9 GeV. This helps to explain the tuning in supersymmetric models, including
split-SUSY models at the PeV scale, while preserving the QCD axion solution to
the strong CP problem. Besides predicting two very weakly-coupled axion-like par-
ticles, the supersymmetric spectrum contains an extra Goldstino, which could be a
viable dark matter candidate.
Primary author
Prof.
Jason Evans
(Korean Institute for Advanced Study)
