Characterization of photodetector temporal response for neutron time-of-flight (nToF) diagnostics at the National Ignition Facility

Gordon, J. M.; Schlossberg, D. J.; Eckart, M. J.; Datte, P. S.; Durand, C. E.; Grim, G. P.; Hartouni, E. P.; Hatarik, R.; Moore, A. S.

doi:10.1063/1.5039390

Title: Characterization of photodetector temporal response for neutron time-of-flight (nToF) diagnostics at the National Ignition Facility

Abstract

The temporal response of a microchannel plate photomultiplier tube used in the suite of neutron time of flight (nToF) diagnostics at the National Ignition Facility has been characterized to reduce uncertainty in, and understanding of, shot parameters obtained from nTOF data. A short singular pulse laser, neutral density glass filters, and electrical attenuators were used to gather statistically significant samples of photodetector impulse response functions (IRF) in rapid succession. Individual components have been absolutely calibrated to minimize systematic uncertainties. The zeroth (collected charge), first (transit time), and second central moments (transit time spread) of the IRF were calculated as either the bias voltage or the amount of light incident on the detector was varied. Timing reference was provided by a monitor photodiode viewing a pickoff of the incident laser pulse. The primary sources of uncertainty are jitter in the monitor photodiode and the statistical variation across our measurement period. The spreads in the first moment, with respect to the timing photodiode, and the square root of the second central moment were found to be less than 50 ps and 150 ps, respectively.

Authors:

Gordon, J. M. ^[1];

^[2]; Eckart, M. J. ^[2]; Datte, P. S. ^[2]; Durand, C. E. ^[2]; Grim, G. P. ^[2];

^[2]; Hatarik, R. ^[2]; Moore, A. S. ^[2]

Univ. of California, Berkeley, CA (United States)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Publication Date:: Mon Oct 01 00:00:00 EDT 2018

Research Org.:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:: USDOE Office of Science (SC)

OSTI Identifier:: 1545518

Alternate Identifier(s):: OSTI ID: 1477527

Grant/Contract Number:: AC52-07NA27344

Resource Type:: Accepted Manuscript

Journal Name:: Review of Scientific Instruments

Additional Journal Information:: Journal Volume: 89; Journal Issue: 10; Journal ID: ISSN 0034-6748

Publisher:: American Institute of Physics (AIP)

Country of Publication:: United States

Language:: English

Subject:: 47 OTHER INSTRUMENTATION; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

Citation Formats


                    Gordon, J. M., Schlossberg, D. J., Eckart, M. J., Datte, P. S., Durand, C. E., Grim, G. P., Hartouni, E. P., Hatarik, R., and Moore, A. S. Characterization of photodetector temporal response for neutron time-of-flight (nToF) diagnostics at the National Ignition Facility.  United States: N. p., 2018. 
Web.  doi:10.1063/1.5039390.

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                    Gordon, J. M., Schlossberg, D. J., Eckart, M. J., Datte, P. S., Durand, C. E., Grim, G. P., Hartouni, E. P., Hatarik, R., & Moore, A. S. Characterization of photodetector temporal response for neutron time-of-flight (nToF) diagnostics at the National Ignition Facility.  United States.  https://doi.org/10.1063/1.5039390

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                    Gordon, J. M., Schlossberg, D. J., Eckart, M. J., Datte, P. S., Durand, C. E., Grim, G. P., Hartouni, E. P., Hatarik, R., and Moore, A. S. Mon .  
"Characterization of photodetector temporal response for neutron time-of-flight (nToF) diagnostics at the National Ignition Facility".  United States.  https://doi.org/10.1063/1.5039390.  https://www.osti.gov/servlets/purl/1545518.

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@article{osti_1545518,

  title        = {Characterization of photodetector temporal response for neutron time-of-flight (nToF) diagnostics at the National Ignition Facility},

  author       = {Gordon, J. M. and Schlossberg, D. J. and Eckart, M. J. and Datte, P. S. and Durand, C. E. and Grim, G. P. and Hartouni, E. P. and Hatarik, R. and Moore, A. S.},

  abstractNote = {The temporal response of a microchannel plate photomultiplier tube used in the suite of neutron time of flight (nToF) diagnostics at the National Ignition Facility has been characterized to reduce uncertainty in, and understanding of, shot parameters obtained from nTOF data. A short singular pulse laser, neutral density glass filters, and electrical attenuators were used to gather statistically significant samples of photodetector impulse response functions (IRF) in rapid succession. Individual components have been absolutely calibrated to minimize systematic uncertainties. The zeroth (collected charge), first (transit time), and second central moments (transit time spread) of the IRF were calculated as either the bias voltage or the amount of light incident on the detector was varied. Timing reference was provided by a monitor photodiode viewing a pickoff of the incident laser pulse. The primary sources of uncertainty are jitter in the monitor photodiode and the statistical variation across our measurement period. The spreads in the first moment, with respect to the timing photodiode, and the square root of the second central moment were found to be less than 50 ps and 150 ps, respectively.},

  doi          = {10.1063/1.5039390},

  journal      = {Review of Scientific Instruments},

  number       = 10,

  volume       = 89,

  place        = {United States},

  year         = {Mon Oct 01 00:00:00 EDT 2018},

  month        = {Mon Oct 01 00:00:00 EDT 2018}

}

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Works referenced in this record:

A New Neutron Time-of-Flight Detector to Measure the MeV Neutron Spectrum at the National Ignition Facility
journal, January 2014

Hatarik, Robert; Caggiano, Joseph A.; Glebov, Vladimir
Plasma and Fusion Research, Vol. 9, Issue 0
DOI: 10.1585/pfr.9.4404104

Analysis of the neutron time-of-flight spectra from inertial confinement fusion experiments
journal, November 2015

Hatarik, R.; Sayre, D. B.; Caggiano, J. A.
Journal of Applied Physics, Vol. 118, Issue 18
DOI: 10.1063/1.4935455

A fused silica Cherenkov radiator for high precision time-of-flight measurement of DT γ and neutron spectra (invited)
journal, October 2018

Moore, A. S.; Schlossberg, D. J.; Hartouni, E. P.
Review of Scientific Instruments, Vol. 89, Issue 10
DOI: 10.1063/1.5039322

Impulse responses of visible phototubes used in National Ignition Facility neutron time of flight diagnostics
journal, September 2016

Datte, P. S.; Eckart, M.; Moore, A. S.
Review of Scientific Instruments, Vol. 87, Issue 11
DOI: 10.1063/1.4962039

Works referencing / citing this record:

Uncertainty analysis of response functions and γ-backgrounds on T _ion and t ₀ measurements from Cherenkov neutron detectors at the National Ignition Facility (NIF)
journal, October 2018

Hartouni, E. P.; Beeman, B.; Eckart, M. J.
Review of Scientific Instruments, Vol. 89, Issue 10
DOI: 10.1063/1.5038816

A fused silica Cherenkov radiator for high precision time-of-flight measurement of DT γ and neutron spectra (invited)
journal, October 2018

Moore, A. S.; Schlossberg, D. J.; Hartouni, E. P.
Review of Scientific Instruments, Vol. 89, Issue 10
DOI: 10.1063/1.5039322

Ab initio response functions for Cherenkov-based neutron detectors
journal, October 2018

Schlossberg, D. J.; Moore, A. S.; Beeman, B. V.
Review of Scientific Instruments, Vol. 89, Issue 10
DOI: 10.1063/1.5039399

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Similar Records

Title: Characterization of photodetector temporal response for neutron time-of-flight (nToF) diagnostics at the National Ignition Facility

Abstract

Citation Formats

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A New Neutron Time-of-Flight Detector to Measure the MeV Neutron Spectrum at the National Ignition Facility
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