Speaker
Description
We revisited the theoretical implications of the study of the
so-called $D$-coefficient which is a P-conserving and T-violating
correlation in the polarized neutron beta decay. While existing
literature argued that any operator that generates this coefficient
will inevitably generate various electric dipole moments in loop
level and the latter set a much stringent bound than the direct
detection, we pointed out that there exists a class of dimension-6
operators involving right-handed neutrinos that contribute to this
correlation in second order and receive no stringent bound from
current upper bounds of electric dipole moments. Assuming a natural
size of the dimensionless Wilson coefficients, the current upper
bound on the neutron $D$-coefficient implies a new physics scale of
$\Lambda>1$TeV.
