description of fission observables. Released November 26, 2016.
- Modification December 19, 2016. (A technical mistake, introduced on
Dec. 16 and leading to wrong results, has been corrected. Sorry about
this. This is not related to the notice below.)
- Modified June 22, 2017. (Typo in DEFO.bas corrected, thanks to
Loic Cole. This correstion cures the problem of an eventually
apprearing endless loop. It should not have any influence on the
- Modified July 1, 2017. (Output of fission probabilities added.)
- Modified July 29, 2017. (Input options from file extended, see README file for details.)
Last modified October 30, 2017: (Spurious structure in pre-neutron yields at exact symmetry removed.)
There exists also an updated version (only available as complete package, see below) with extended input
and output options and a few technical corrections. The results should
Important notice: By verifying the results of GEF 2016/1.1 at higher
initial excitation energies (above 10 MeV), a systematic overestimation of the
fragment excitation energies (TXE) was observed. The reason was a too
strong energy dependence of the shape fluctuations at scission. This
problem should be solved in the version 2016/1.2.
This problem does not exist for
the Stand-alone version (GEFSUB). That means that
the subroutines of versions 2016/1.1 and 2016/1.2 are identical and
correspond to the stand-alone version GEF 2016/1.2.
An extended version of GEF-2016/1.2 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.
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)
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
version, a GUI is provided, written in JustBasic (c). The Windows
version runs also on Linux with Wine (d). The Windows version should also run on OS X (e) with Wine (d). (Did somebody try it?)
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).
- Start GEF.bat in a
- Fill in the input mask of the graphical user interface and start
- Output is written to file \out\...
Quick start on Linux:
- Download the binaries.
- Make sure that the binary file GEF is executable.
- Enter ./GEF in a command
- Answer the input dialogue.
- Output is written to file
Input mask of the graphical user interface:
For Windows and Linux
Updated version of the complete package (2. 5. 2018). (Extended input and output options and some technical corrections. The physics is not changed.)
Updated special version
of the complete package (9. 8. 2018). (Like the updated version; in
addition, the shell effect in the symmetric fission valley is washed
out with increasing excitation energy.)
(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)
Input files for extended input options
Distribution of entrance energies (example)
List of input parameters (example)
See Readme file
for more detailed information.
Data tables in XML 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.
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
Notice to the users of the subroutine version of GEF:
The subroutine GEFSUB
2016/V1.2 is identical to the subroutine GEFSUB 2016/V1.1. (See notice
above.) Thus, there is no need for updating from GEFSUB 2016/V1.1 to
GEFSUB 2016/V1.2. The packages below are only provided for practical
Technical description of the subroutine