In Situ Pu isotopic measurements using electromechanically cooled HPGe detectors at PFPF Page: 3 of 11
This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
In Situ Pu Isotopic Measurements Using Electromechanically
Cooled HPGe Detectors at PFPF
Tracy R. Wenz and Howard O. Menlove
Los Alamos National Laboratory
Los Alamos, NM 87545 USA
Hajime Maruyama, Shigeo Fujiwara,
and Saburo Takahashi, Kouichi Konno
Japan Nuclear Cycle Development Institute
Tokai-mura, Ibaraki-kon, Japan
A high-resolution gamma ray spectroscopy (HRGS) system has been installed at the
Advanced Material Accountancy Glovebox Assay (AMAGB) System so that neutron and gamma
ray measurements can occur simultaneously on material transfer containers. This equipment was
installed in August 2000 at the Plutonium Fuel Production Facility (PFPF) in Japan. It is
anticipated that placing the HRGS system at the neutron assay station will save a few person-days
per IAEA inspection because it will no longer be necessary to take samples from the transfer
container for isotopic analysis at another assay station. The HRGS system consists of a 25%
relative efficiency coaxial detector with electromechanical cooling and digital signal processing.
The digital spectrometer has the benefit of increasing throughput, improving energy resolution, and
extending the lifetime of neutron damaged HPGe detectors as compared to analog spectrometers.
The gamma-ray system is used to verify the Pu isotopic composition and 241Am concentration in
transfer containers of MOX. The 240Pueff fraction is calculated from the isotopic data and is used to
convert the neutron assay data to total grams plutonium. The results of performance tests and
calibration measurements using this system are reported in this paper.
The Advanced Material Accountancy Glovebox (AMAGB) assay system is used to assay
plutonium content of mixed oxide (MOX) reactor fuel materials in the form of powder and pellets.
Two systems are located at the Plutonium Fuel Production Facility (PFPF) in Japan, which is
operated by the Japan Nuclear Cycle Development Institute (JNC). The assay system is used by the
International Atomic Energy Agency (IAEA), the Japan Safeguards Office (JSGO), and JNC during
monthly safeguards inspections.
The AMAGB assay system consists of two components: neutron and gamma-ray assay. The
neutron measurement determines the 240Pueff mass using the known-alpha analysis method.1 The
gamma-ray measurement determines the Pu and 241Am isotopic fractions in the sample, using either
the FRAM2 or MGA3'4 analysis software. The isotopic software calculates the 240Pueff fraction that
is used to convert the neutron assay mass to total grams of Pu. One unit is located around a material
accountancy glovebox, and the other is located around a supplemental transfer line that connects
gloveboxes located in different areas together. The neutron detectors are permanently mounted
around the glovebox transfer lines, so the neutron assay can be performed in attended or unattended
mode. The detectors for the gamma-ray measurement have to be positioned at the neutron assay
system for every measurement (these are not permanently mounted), so this measurement is
performed only in attended mode for this particular application.
Here’s what’s next.
This article can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Article.
Wenz, T. R. (Tracy R.); Menlove, Howard O.; Maruyama, H. (Hajime); Fujiwara, S. (Shigeo) & Takahashi, S. (Saburo). In Situ Pu isotopic measurements using electromechanically cooled HPGe detectors at PFPF, article, January 1, 2001; United States. (https://digital.library.unt.edu/ark:/67531/metadc933990/m1/3/: accessed April 25, 2019), University of North Texas Libraries, Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.