Title: Improved Localization Precision and Angular Resolution of a Cylindrical, Time-Encoded Imaging System From Adaptive Detector Movements

Abstract

To the first-order, the localization precision and angular resolution of a cylindrical, time-encoded imaging (c-TEI) system is governed by the geometry of the system. Improving either measure requires increasing the mask radius or decreasing the detector diameter, both of which are undesirable. We propose an alternative option of repositioning the detector within the mask to increase the detector-to-mask distance in the direction of a source thereby improving the localization precision and angular resolution in that direction. Since the detector-to-mask distance only increases for a small portion of the field-of-view (FOV), we propose implementing adaptive imaging where one leverages data collected during the measurement to optimize the system configuration. This paper utilizes both simulations and experiments to set upper bounds on the potential gain from adaptive detector movements for one and two sources in the FOV. When one source is present, adaptive detector movements can improve the localization precision and angular resolution by 20% for a source at 90 cm and by 32% for a far-field source. When two sources are present, adaptive detector movements can improve localization precision and angular resolution by up to 50% for sources that are ~10° apart (90 cm from system). We experimentally verify these resultsmore » through maximum likelihood estimation of the source position(s) and image reconstruction of point sources that are close together. As a demonstration of an adaptive imaging algorithm, we image a complex arrangement of special nuclear material at the Zero Power Physics Reactor facility at Idaho National Laboratory.« less

Authors:

Shah, Niral P.  ^[1];

• Search DOE PAGES for author "Shah, Niral P."
• Search DOE PAGES for ORCID "0000-0002-7299-0774"

Marleau, Peter ^[2]; Fessler, Jeffrey A.  ^[1];

• Search DOE PAGES for author "Fessler, Jeffrey A."
• Search DOE PAGES for ORCID "0000-0001-9998-3315"

Chichester, David L.  ^[3];

• Search DOE PAGES for author "Chichester, David L."
• Search DOE PAGES for ORCID "0000-0002-8511-4458"

Wehe, David K.  ^[1]

• Search DOE PAGES for author "Wehe, David K."
• Search DOE PAGES for ORCID "0000-0002-8519-6334"

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+ Show Author Affiliations

1. Univ. of Michigan, Ann Arbor, MI (United States)
2. Sandia National Lab. (SNL-CA), Livermore, CA (United States)
3. Idaho National Lab. (INL), Idaho Falls, ID (United States)

Publication Date:

Thu Feb 18 00:00:00 EST 2021

Research Org.:

Sandia National Lab. (SNL-CA), Livermore, CA (United States); Univ. of Michigan, Ann Arbor, MI (United States)

Sponsoring Org.:

USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:

1782574

Alternate Identifier(s):

OSTI ID: 1804859

Report Number(s):

SAND-2021-1208J
Journal ID: ISSN 0018-9499; 693809; TRN: US2210022

Grant/Contract Number:  

AC04-94AL85000; NA-241; NA0002534; NA0003920; NA0003525

Resource Type:

Accepted Manuscript

Journal Name:

IEEE Transactions on Nuclear Science

Additional Journal Information:

Journal Volume: 68; Journal Issue: 4; Journal ID: ISSN 0018-9499

Publisher:

IEEE

Country of Publication:

United States

Language:

English

Subject:

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; adaptive imaging; angular resolution; cylindrical time-encoded imaging (c-TEI); fast neutron imaging; gammaray imaging; source localization