Development of ultra-cold neutron detectors with spatial resolution of several ten nanometers for the measurement of quantum effect of ultra-cold neutrons in the earth's gravitational field

2015 Fiscal Year Final Research Report

• Project/Area Number: 26800132
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Nagoya University
• Principal Investigator: Naganawa Naotaka 名古屋大学, 未来材料・システム研究所, 研究員 (60402434)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 中性子検出器 / 高分解能 / 原子核乾板 / 重力 / 超冷中性子

Outline of Final Research Achievements

Neutron detectors with extremely high spatial resolution are having been developed for the measurement of position distribution of ultra-cold neutrons in quantized states in the earth’s gravitational field as tests of gravitational invers-square law and equality of gravitational and inertial mass.
A detector made by loading LiNO3 into fine-grained nuclear emulsion was exposed to thermal and cold neutrons and absorption events were detected. Its spatial resolution turned out to be about 0.5 micron, which is higher than other detectors by an order of magnitude. Its detection efficiency turned out to be as expected.
Another detector was made by coating 10B layer of 10nm-thick with fine-grained nuclear emulsion. Its spatial resolution should be several 10nm. It was exposed to cold neutrons, and absorption events were detected. Stabilization of 10B layer is proceeding.

Free Research Field

素粒子物理学