GEF-2023-2-1

GEF 2023/2.1

General description of fission observables,
released on April 14, 2023.

Short characterisation of GEF 2023/2.1:

Compared to GEF 2023/1.2, the description of fission yields in the region around 226Th is revised by a modified calculation of the macroscopic potential, a suppression of compact configurations in the region of 230Th at low excitation energies is introduced and an authorized extension up to Z=120 an N=200 is proposed.
GEF 2023/1.2 provides an overall improved description of fission, also in critical regions. A further optimization of the model parameters is underway.

Mass yields of U235T in comparison with JEFF 3.3

The mass distribution of 235U(nth,f) from GEF-2019/1.1 (red points) in comparison with the JEFF 3.3 evalution (black symbols with error bars). The calculated contributions from different fission channels are traced in green. 10 million events have been calculated.

An extended version of GEF-2023/2.1 that includes delayed processes (output of delayed-neutron multiplicities, delayed-neutron emitters, cumulative fission-fragment yields in ENDF format) is available on demand. It provides also an option for producing random files of fission-fragment yields in ENDF format.

We are happy about any feed-back (mail to schmidt-erzhausen<at>t_online.de). This helps to correct errors, to improve the quality of the model and to better respond to the needs and preferences of the users.

Use of the GEF code is subject to the GNU GENERAL PUBLIC LICENSE agreement that you find here: <License>.

Stand-alone version (Monte-Carlo method)

The stand-alone version of the GEF code is written in FreeBASIC (a). The FreeBASIC compiler produces binary code from the same source on Windows (b) and on Linux. The executable uses the C library. For the Windows version, a GUI is provided, written in JustBasic (c). The Windows version runs also on Linux with Wine (d). The Windows version runs also on OS X (e) with Wine (d).

a) FreeBASIC is available from http://www.freebasic.net/ with no cost.
b) Windows is either a registered trademark or a trademark of Microsoft Corporation in the United States and/or other countries.
c) JustBasic is available from http://www.justbasic.com/ with no cost.
d) Wine is a windows compatibility layer for Linux and Mac OS X (http://www.winehq.org/).
e) OS X is a trademark of Apple Inc., registered in the U.S. and other countries.

Quick start on Windows:

Download the binaries (that includes some additional files).

Version with nuclear properties from JEFF-3.3 (considers only long-lived isomers)
Version with nuclear properties from NUBASE2016 (considers all known isomers)

Start GEF.bat in a command window.
Fill in the input mask of the graphical user interface and start the calculation.
Output is written to file \out\... .dat.

Quick start on Linux:,

Download the binaries, 64-bit versions.

Version with nuclear properties from JEFF-3.3 (considers only long-lived isomers)
Version with nuclear properties from NUBASE2016 (considers all known isomers)

Make sure that the binary file GEF is executable.
Enter ./GEF in a command window.
Answer the input dialogue.
Output is written to file /out/... .dat.

Windows version Input mask of the graphical user interface:

For Windows and Linux

Complete package

Documentation

Readme file (Technical information, list of relevant publications)
JEFF-Report 24, part I (Comprehensive documentation of the GEF model.)
JEFF-Report 24, part II (Technical information on the GEF code.)

Source (for Windows and Linux)

Source files

Data

Input files for extended input options

Distribution of entrance energies (example)
List of input parameters (example)
See Readme file for more detailed information.

Output

Data tables in XML-assisted format (example)
List-mode file (example) (short sample of most complete event list)
Raw data for the multi-variate distribution of fission-fragment yields from calculations with perturbed parameters (example)
See Readme file for more detailed information.

You may consider using the Windows version of GEF on Linux with Wine in order to profit from the more comfortable input handling offered by the graphical user interface. This option may also solve problems of missing libraries under Linux.

Subroutine (Folding method)

The subroutine aims for being used in combination with other nuclear-reaction codes. For a given fissioning nucleus with excitation energy E* and angular momentum I it calculates complete distributions of a number of fission observables before emission of prompt neutrons and prompt gamma radiation with the GEF model.

Documentation

Technical description of the subroutine

FreeBASIC version

In preparation

FORTRAN version

In preparation