Solar Neutron Tracking (SONTRAC) spectrometer

Solar Neutron Tracking (SONTRAC) spectrometer
Principal Investigator	Georgia De Nolfo
Institution	NASA Godard Space Flight Center (GSFC)
Technology Readiness Level	4
Instrument Type	Neutron spectrometer
Project Status	Active
Project ID	20-HTIDS-20-0014

Overview

Fast neutrons (> 0.5 MeV) are ubiquitous, originating from nuclear interactions in the solar corona, within planetary atmospheres, and in the lunar regolith. However, measurements of fast neutrons of solar origin are limited due to the challenges imposed by high backgrounds and the relatively short lifetime of free neutrons. Traditional double-scatter neutron spectrometers require an incident neutron to elastically scatter in two widely separated detectors, allowing the reconstruction of the incident neutron energy and direction. While double-scatter spectrometers are well-proven, they suffer from low effective area due to spacecraft size constraints and limited resolution. The Solar Neutron TRACking (SONTRAC) concept overcomes these limitations through the use of stacked planes of plastic scintillating fibers arranged in an orthogonal configuration, to measure the ionization tracks of recoil protons. The recoil proton energy and direction supplant the need to measure the neutron time-of-flight between detectors, thereby increasing the effective area and detection efficiency. SONTRAC employs modern, miniature silicon photomultipliers (SiPM) to measure the light output from the fibers.

Presentations, Publications, and Patents

Presentations

• de Nolfo, G. A et al., The Solar Neutron TRACking (SONTRAC)I nstrument for the Detection of Fast Neutrons, Nucl. Science and medical imaging/ I EEE Oct 2022
• Mitchell, J. G. et al., Calibration of the Solar Neutron TRACking (SONTRAC) Instrument, Nucl. Science and medical imaging/ I EEE Oct 2022
• Suarez, G., NASA-UNH SONTRAC Track Reconstruction and Results for 67 MeV Neutrons, Nucl. Science and medical imaging/ I EEE Oct 2022
• de Nolfo G. A. et al., Closing the Gap on Particle Acceleration with Neutrons, SHINE 2022

Publications

• de Nolfo, G. A. et al., Development of the Solar Neutron TRACking (SONTRAC) Concept, Development of the Solar Neutron TRACking (SONTRAC) Concept, 10.22323/1.395.01250
• de Nolfo, G. A. et al., The Solar Neutron TRACking (SONTRAC) Instrument for the Detection of Fast Neutrons, MIM-A, 2022
• Mitchell, J. G. et al., The Physics of Solar Energetic Particles and Their Detection, PhD. Disseration, The George Washington University Department of Physics, 2022
• Suarez, G., Advanced Electronics and Post-Processing Algorithm for the SONTRAC 3D Neutron Spectrometer, PhD. Dissertation, The University of New Hampshire Department of Electrical and Computer Engineering, 2022