Speaker
Dr
Andreas Athenodorou
(University of Cyprus)
Description
We extract the neutron electric dipole moment (nEDM) |d_n| on configurations produced with N_f=2+1+1 twisted mass
fermions with lattice spacing of a=0.082fm and a light quark mass that corresponds to M_{\pi}=370 MeV. We do so by
evaluating the CP-odd form factor F_3 for small values of the vacuum angle \theta at the limit of zero momentum
transfer. This limit is taken using a parametrization of the momentum dependence and performing a fit as well as
using the position space methods we refer to as "continuum derivative" and "direct computation". The extraction of the
CP-odd form factor F_3 requires the evaluation of the field theoretical topological charge. We measure the
topological charge via cooling and gradient flow using the ordinary Wilson, Symanzik tree-level improved and Iwasaki
actions for smoothing. We obtain consistent results for all choices of smoothing actions, smoothing procedures and
momentum dependence treating techniques. We report an nEDM of |d_n|/ \theta = -0.036(11)(7) e fm.
Primary author
Dr
Andreas Athenodorou
(University of Cyprus)
Co-authors
Prof.
Constantia Alexandrou
(University of Cyprus)
Prof.
Giannis Koutsou
(Cyprus Institute)
Prof.
Karl Jansen
(DESY Zeuthen)
Dr
Konstantin Ottnad
(HISKP University of Bonn)
Dr
Kyriakos Hadjiyiannakou
(University of Cyprus)
Dr
Marcus Petschlies
(HISKP University of Bonn)
Dr
Martha Constantinou
(University of Cyprus)
