Support an improved measurement of the lifetime of the neutron, which is a fundamental constant limiting some important issues in astrophysics and cosmology, such as the amount of primordial helium…

This $100,000 cooperative agreement from the National Institute of Standards and Technology will support improved measurement of the neutron lifetime through September 2025. Funded under the Measurement and Engineering Research and Standards program, key activities include non-destructive measurement of the neutron lifetime using a Penning ion trap. Neutrons will decay into protons while in flight through the trap, with the protons captured and counted in-situ and via radio-frequency current, providing an independent calibration for the external detector. Outcomes aim to establish the neutron lifetime measurement with uncertainty well below one second. Beneficiaries include metrological institutes through improved radiation detection standards, and institutions of higher learning given the measurement's role in nuclear and particle physics, astrophysics, and cosmology. The University of Illinois at Champaign-Urbana is the sole awardee. No subawards are included.

Purpose

The purpose of this grant is to support an improved measurement of the lifetime of the neutron, which is a fundamental constant limiting some important issues in astrophysics and cosmology, such as the amount of primordial helium arising from big bang nucleosynthesis.

Activities

The proposed work will measure the neutron lifetime by observing the neutron decay into a proton while in flight through a penning ION trap. This non-destructive method captures the proton from the decay and counts the stored protons in-situ via the radio-frequency current induced by their motions, providing an independent calibration of the external detector for counting the protons when they are dumped from the ION trap.

Expected outcomes

Success is expected to establish the measurement of the neutron lifetime (about 878 s) with an uncertainty well below 1 s.

Intended beneficiaries

This work will benefit metrological institutes via improved standards for radiation detection. Resolution of the discrepancy (about 15 standard deviations) between the 'beam' and 'bottle' techniques for neutron lifetime measurement will benefit institutions of higher learning because of its central role in many phenomena/projects in nuclear and particle physics, in astrophysics and in cosmology.

Subrecipient activities

There are no subawards in this project.