Speaker
Mr
Tomohiro Takesako
(ICRR, University of Tokyo)
Description
We evaluate the effective mass of a scalar field $¥phi$ coupled to thermal plasma through Planck-suppressed interactions.
We find it useful to rescale the coupled fields so that all the $¥phi$-dependences are absorbed into the yukawa and gauge couplings,
which allows us to read off the leading order contributions to the effective mass $¥tilde m_{¥phi}$ from the 2-loop free energy calculated
with the rescaled couplings.
We give an analytical expression for $¥tilde m_{¥phi}$ at a sufficiently high temperature
in the case where $¥phi$ is coupled to the MSSM chiral superfields through non-minimal
K$¥ddot{¥text{a}}$hler potential.
We find that $|¥tilde m_{¥phi}^2|$ is about $10^{-3} H^2 ¥sim 10^{-2} H^2$ at the leading order in terms of the couplings for typical parameter sets, where $H$ is the Hubble expansion rate in the radiation-dominated era.
Primary author
Mr
Tomohiro Takesako
(ICRR, University of Tokyo)
Co-authors
Prof.
Fuminobu Takahashi
(Tohoku University)
Prof.
Masahiro Kawasaki
(ICRR, University of Tokyo)
