Bare Neutron Counter and Neutron Monitor Response to Cosmic Rays During a 1995 Latitude Survey

©2018. American Geophysical Union. All Rights Reserved. Neutron monitors of standard design (IGY or NM64) are employed worldwide to study variations in the flux of galactic cosmic rays and solar energetic particles in the GeV range. The design minimizes detector response to neutrons below ∼10 MeV pr...

Full description

Saved in:
Bibliographic Details
Main Authors: W. Nuntiyakul, A. Sáiz, D. Ruffolo, P. S. Mangeard, P. Evenson, J. W. Bieber, J. Clem, R. Pyle, M. L. Duldig, J. E. Humble
Format: Journal
Published: 2018
Subjects:
Online Access:https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85052968884&origin=inward
http://cmuir.cmu.ac.th/jspui/handle/6653943832/62516
Tags: Add Tag
No Tags, Be the first to tag this record!
Institution: Chiang Mai University
id th-cmuir.6653943832-62516
record_format dspace
spelling th-cmuir.6653943832-625162018-11-29T07:43:57Z Bare Neutron Counter and Neutron Monitor Response to Cosmic Rays During a 1995 Latitude Survey W. Nuntiyakul A. Sáiz D. Ruffolo P. S. Mangeard P. Evenson J. W. Bieber J. Clem R. Pyle M. L. Duldig J. E. Humble Agricultural and Biological Sciences Earth and Planetary Sciences Environmental Science ©2018. American Geophysical Union. All Rights Reserved. Neutron monitors of standard design (IGY or NM64) are employed worldwide to study variations in the flux of galactic cosmic rays and solar energetic particles in the GeV range. The design minimizes detector response to neutrons below ∼10 MeV produced by cosmic ray interactions in the ambient medium. Increasingly, however, such neutrons are of interest as a means of obtaining spectral information on cosmic rays, for studies of soil moisture, and for nuclear threat detection. Bare neutron counters, a type of lead-free neutron monitor, can detect such neutrons, but comparatively little work has been done to characterize the dependence of their count rate on cutoff rigidity. We analyze data from three bare neutron counters operated on a ship together with a three-tube NM64 monitor from November 1995 to March 1996 over a wide range of magnetic latitude, that is, a latitude survey. The bare counter design used foamed-in-place polyurethane insulation to keep the temperature uniform and to some extent moderate high-energy neutrons. When the ship was near land, the bare/NM64 count rate ratio was dramatically higher. Considering only data from open sea, the bare and NM64 pressure coefficients are not significantly different. We determine the response function of these bare counters, which is weighted to Galactic cosmic rays of lower energy than the NM64. This measurement of the response function may improve determination of the spectral index of solar energetic particles and Galactic cosmic rays from a comparison of bare and NM64 count rates. 2018-11-29T07:29:53Z 2018-11-29T07:29:53Z 2018-09-01 Journal 21699402 21699380 2-s2.0-85052968884 10.1029/2017JA025135 https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85052968884&origin=inward http://cmuir.cmu.ac.th/jspui/handle/6653943832/62516
institution Chiang Mai University
building Chiang Mai University Library
country Thailand
collection CMU Intellectual Repository
topic Agricultural and Biological Sciences
Earth and Planetary Sciences
Environmental Science
spellingShingle Agricultural and Biological Sciences
Earth and Planetary Sciences
Environmental Science
W. Nuntiyakul
A. Sáiz
D. Ruffolo
P. S. Mangeard
P. Evenson
J. W. Bieber
J. Clem
R. Pyle
M. L. Duldig
J. E. Humble
Bare Neutron Counter and Neutron Monitor Response to Cosmic Rays During a 1995 Latitude Survey
description ©2018. American Geophysical Union. All Rights Reserved. Neutron monitors of standard design (IGY or NM64) are employed worldwide to study variations in the flux of galactic cosmic rays and solar energetic particles in the GeV range. The design minimizes detector response to neutrons below ∼10 MeV produced by cosmic ray interactions in the ambient medium. Increasingly, however, such neutrons are of interest as a means of obtaining spectral information on cosmic rays, for studies of soil moisture, and for nuclear threat detection. Bare neutron counters, a type of lead-free neutron monitor, can detect such neutrons, but comparatively little work has been done to characterize the dependence of their count rate on cutoff rigidity. We analyze data from three bare neutron counters operated on a ship together with a three-tube NM64 monitor from November 1995 to March 1996 over a wide range of magnetic latitude, that is, a latitude survey. The bare counter design used foamed-in-place polyurethane insulation to keep the temperature uniform and to some extent moderate high-energy neutrons. When the ship was near land, the bare/NM64 count rate ratio was dramatically higher. Considering only data from open sea, the bare and NM64 pressure coefficients are not significantly different. We determine the response function of these bare counters, which is weighted to Galactic cosmic rays of lower energy than the NM64. This measurement of the response function may improve determination of the spectral index of solar energetic particles and Galactic cosmic rays from a comparison of bare and NM64 count rates.
format Journal
author W. Nuntiyakul
A. Sáiz
D. Ruffolo
P. S. Mangeard
P. Evenson
J. W. Bieber
J. Clem
R. Pyle
M. L. Duldig
J. E. Humble
author_facet W. Nuntiyakul
A. Sáiz
D. Ruffolo
P. S. Mangeard
P. Evenson
J. W. Bieber
J. Clem
R. Pyle
M. L. Duldig
J. E. Humble
author_sort W. Nuntiyakul
title Bare Neutron Counter and Neutron Monitor Response to Cosmic Rays During a 1995 Latitude Survey
title_short Bare Neutron Counter and Neutron Monitor Response to Cosmic Rays During a 1995 Latitude Survey
title_full Bare Neutron Counter and Neutron Monitor Response to Cosmic Rays During a 1995 Latitude Survey
title_fullStr Bare Neutron Counter and Neutron Monitor Response to Cosmic Rays During a 1995 Latitude Survey
title_full_unstemmed Bare Neutron Counter and Neutron Monitor Response to Cosmic Rays During a 1995 Latitude Survey
title_sort bare neutron counter and neutron monitor response to cosmic rays during a 1995 latitude survey
publishDate 2018
url https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85052968884&origin=inward
http://cmuir.cmu.ac.th/jspui/handle/6653943832/62516
_version_ 1681425821670047744