Present state of the SOURCES computer code Page: 2 of 11
This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to UNT Digital Library by the UNT Libraries Government Documents Department.
Extracted Text
The following text was automatically extracted from the image on this page using optical character recognition software:
PRESENT STATE OF THE SOURCES COMPUTER CODE
E.F. Shores
Los Alamos National Laboratory
PO Box 1663, MS K483
Los Alamos, NM, 87545, USA
505.665.7643
eshores@lanl.govSUMMARY
In various stages of development for over two
decades, the SOURCES computer code continues
to calculate neutron production rates and spectra
from four types of problems: homogeneous media,
two-region interfaces, three-region interfaces and
that of a monoenergetic alpha particle beam
incident on a slab of target material.'
Graduate work at the University of Missouri -
Rolla, in addition to user feedback from a tutorial
course, provided the impetus for a variety of code
improvements. Recently upgraded to version 4B,
initial modifications to SOURCES focused on
updates to the "tapes" decay data library. Shortly
thereafter, efforts focused on development of a
graphical user interface for the code. This paper
documents the Los Alamos SOURCES Tape1
Creator and Library Link (LASTCALL) and
describes additional library modifications in more
detail. Minor improvements and planned
enhancements are discussed.
I. HISTORY
The following section was written for the updated
user's manual planned for release during the next
major code upgrade (version 5A).
The SOURCES-5A code has been under
development since the early 1980's with continuing
improvements made in both methods and data.
Effectively version 1.0, the original version of
SOURCES was actually named POFEAL and
primarily used for calculating the probability of an
(c,n) interaction with nuclide i by an alpha particle
prior to stopping in the material (P OF E-ALpha).2
Developed by the Los Alamos Applied Nuclear
Science Group (then T-2), the code was intended
to calculate neutron production in source materials
such as oxide and carbide fuels, plutonium metal,
aqueous process solutions, and uranium
enrichment processes. The Safeguards
Technology Group (then Q-1) furthered interest
and POFEAL's capabilities were improved by
including spectral calculations and makingadjustments to the calculational algorithms.3 It was
during this time in 1982 when the code was
actually referred to as SOURCES and
distinguished from POFEAL. Although often
assumed an acronym, SOURCES was simply a
name for the code given by the primary developer,
W.B. Wilson. In addition to the original probability
calculations, SOURCES (effectively version 2.0)
was then able to calculate neutron "sources" from
the spontaneous fission of actinide nuclides, the
(c,n) reactions of their decay alpha particles with
light nuclides, and delayed neutrons.
Public release via the Radiation Safety Information
Computational Center (RSICC) required both a
"frozen" version of the code for control purposes
and a method to track changes. Consequently, a
naming convention was chosen in 1997 when the
two-region interface problem was added. In place
for version 3A, the new convention designated a
trailing numeral to indicate a major code release
followed by a letter to designate any minor
improvements. Thus version 3A was the third
major version of the code. The capability to
calculate (c,n) source rates and spectra for three-
region interface problems was added for 1999's
version 4A. Minor data improvements to the tape
library upgraded version 4A to 4B in 2001.
Although a user's manual did not exist until version
3A, and versions 4A and 5A each were issued with
an updated manual, minor upgrades typically
would not warrant efforts to produce a revised
document. The user is encouraged to monitor the
code distributor's (RSICC) publications (e.g.
newsletter and web-site) for updates, notices, and
associated documentation related to any
improvements.
Existing for both unix and DOS-based computing
platforms, SOURCES-5A currently consists of a
FORTRAN 77 (F77) source code, a user-created
input file, up to six output files, and four library
files. The user's manual is applicable for both
types of computing platforms although installation
may vary on each system. Appendix C of the
Upcoming Pages
Here’s what’s next.
Search Inside
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.
Shores, E. F. (Erik F.). Present state of the SOURCES computer code, article, January 1, 2002; United States. (https://digital.library.unt.edu/ark:/67531/metadc930973/m1/2/: accessed April 16, 2024), University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.