A new approach to the experiment intended to test the weak equivalence principle for the neutron

TL;DR

This paper proposes a novel experimental method using ultracold neutrons with a discrete energy spectrum to test the weak equivalence principle, eliminating the need for precise initial energy or geometric measurements.

Contribution

It introduces a new free fall experiment approach utilizing neutron diffraction from a moving phase grating to test gravitational effects on neutrons.

Findings

Method allows testing without knowing initial neutron energy.

Uses time-of-flight measurements for different energy lines.

Potentially improves precision in weak equivalence principle tests.

Abstract

A new approach to the free fall experiment with UCN is proposed. The idea is that the experiment is performed with neutrons from different equidistant lines of a discrete energy spectrum with a precisely known distance between the lines. Such a spectrum may be formed by neutron diffraction from a moving phase grating. Time-of-flight values of neutrons from different lines of the spectrum must be measured. Neither the initial neutron energy, nor the geometry parameters of the installation are required to be known in this method.