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تسجيل مستخدم جديدMeasurement of the permanent electric dipole moment of the neutron
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We present the result of an experiment to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute using Ramseys method of separated oscillating magnetic fields with ultracold neutrons (UCN). Our measurement stands in the long history of EDM experiments probing physics violating time reversal invariance. The salient features of this experiment were the use of a Hg-199 co-magnetometer and an array of optically pumped cesium vapor magnetometers to cancel and correct for magnetic field changes. The statistical analysis was performed on blinded datasets by two separate groups while the estimation of systematic effects profited from an unprecedented knowledge of the magnetic field. The measured value of the neutron EDM is $d_{rm n} = (0.0pm1.1_{rm stat}pm0.2_{rm sys})times10^{-26}e,{rm cm}$.
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Until now no electric dipole moment of the neutron (nEDM) has been observed. Why it is so vanishingly small, escaping detection for the last 65 years, is not easy to explain. In general it is considered as one of the most sensitive probes for the vio
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Until this day no electric dipole moment of the neutron (nEDM) has been observed. Why it is so vanishing small, escaping detection in the last 50 years, is not easy to explain. In general it is considered as the most sensitive probe for the violation
of the combined symmetry of charge and parity (CP). A discovery could shed light on the poorly understood matter/anti-matter asymmetry of the universe. As nucleon it might one day help to distinguish different sources of CP-violation in combination with measurements of the electron and diamagnetic EDMs. This proceedings articles presents an overview of the most important concepts in searches for an nEDM and presents a brief overview of the world wide efforts.
We propose a novel approach in a search for the neutron electric dipole moment (EDM) by taking advantage of signal amplification in a weak measurement, known as weak value amplification. Considering an analogy to the weak measurement that can measure
the spin magnetic moment interaction, we examine an experimental setup with a polarized neutron beam through an external electric field with spatial gradient, where the signal is sensitive to the EDM interaction. In particular, a dedicated analysis of effects from impurities in pre- and post-selections is performed. We show that the weak value amplification occurs where the signal is enhanced by up to two orders of magnitude, and demonstrate a potential sensitivity of the proposed setup to the neutron EDM.
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