Redoubled effect of a neutron spin rotation in deformed noncentrosymmetric crystal for the Bragg diffraction scheme
V. V. Fedorov, I. A. Kuznetsov, E. G. Lapin, S. Yu. Semenikhin, V. V. Voronin
Petersburg Nuclear Physics Institute RAS, 188300 Gatchina, St.Petersburg, Russia
PACS: 14.20.Dh, 61.12.Gz
Abstract
A doubled effect of a neutron spin rotation in the
noncentrosymmetric quartz crystal for the Bragg reflected neutrons from the
deformed exit crystal side is first observed. The effect arises due to a
neutron Schwinger interaction with the crystal and depends on a value of a
crystal deformation near its back exit face. Electric field acting on a
neutron in the quartz crystal is about V/cm. This field affects
the neutron during the whole time of its passage through the crystal both
ways there and back. This time is limited only by the available size of
crystal (14 and 27 cm in our case) or the neutron absorption length.
Observation of such effects gives a real perspective to improve essentially
the scheme and sensitivity of the experiment for a search for neutron
electric dipole moment (EDM) by the crystal-diffraction technique. Moreover,
the presented experimental scheme can be applied for neutron with energy
close to the P wave resonance one to search for T-odd part of a
neutron-nuclei interaction, for example, because of relatively low
requirements to a crystal quality.