The MTV-G (MTV-Gravity) experiment is aiming to test an existence of a strong gravitational field at around nuclear scale, utilizing an electron polarimeter of the MTV (Mott Polarimetry for T-Violation) experiment at TRIUMF, which is searching a large T-Violating electron transverse polarization emitted in a polarized Li-8 beta decay.From 2011, we have started the MTV-G experiment utilizing the MTV detectors, successfully examined the strong gravitational field at the microscopic scale for the first time.We are trying to set new constraint on the possible new Yukawa interaction at sub-mm scale, where violation of gravitational inverse square law is predicted.
th , 2013) The MTV (Mott polarimetry for T-Violation) experiment is running from 2009 at TRIUMF, which aims to search a large non-standard T-Violation in polarized nuclear beta decay. Existence of a large transverse polarization of electrons emitted from polarized Li-8 nuclei, which are produced at TRIUMF-ISAC and stopped inside an aluminum stopper, is investigated. We utilize a Mott polarimeter consists of a CDC (Cylindrical Drift Chamber), measuring backward scattering left-right asymmetry from a thin lead analyzer foil. In this paper, results from the final performance test run using CDC performed in 2012 are described.
We report recent situation of anomaly in spin expectation value found in 9C-9Li mirror pair, recent analysis of the nuclear spin in terms of orbital or intrinsic and proton or neutron, and a result from the study of the G-parity conservation law through β-ray angular correlation in terms of its nuclear orientation.