NEA-1716 TRIPOLI-4.3.3 & 4.4.

1. NAME OR DESIGNATION OF PROGRAM:  TRIPOLI-4.3.3 and TRIPOLI-4.4

3. DESCRIPTION OF PROGRAM OR FUNCTION

TRIPOLI-4 is a general purpose radiation transport code. It uses the Monte Carlo method to simulate neutron and photon behaviour in three-dimensional geometries. The main areas of applications include but are not restricted to: radiation protection and shielding, nuclear criticality safety, fission and fusion reactor design, nuclear instrumentation. In addition, it can simulate electron-photon cascade showers.
  
It computes particle fluxes and currents and several related physical quantities such as, reaction rates, dose rates, heating, energy deposition, effective multiplication factor, perturbation effects due to density, concentration or partial cross-section variations.
  
Types of particles        Neutron, gamma, electron, positron.
  
Nuclear data              ENDF-6 format. Cross sections processed
                          by  NJOY code system. Pointwise cross
                          section representation.  Probability
                          tables (PT) representation possible in
                          unresolved energy range (PT produced by
                          CALENDF code).
  
Energy ranges             For neutrons and gamma the energy range
                          is the same as range specified into the
                          evaluation in ENDF-6 format.
                          Neutrons : 0. - 150 MeV
                          Gamma : 0 - 100 MeV
                          For Electrons/positrons :
                          1 MeV - several GeV (with bremsstrahlung
                          gamma rays).
  
Geometry                  3-D surface and combinatorial, network
                          and network of networks.
  
Sources                   General factorised description: space,
                          energy, angle, time
  
Calculated physical       See table below.
quantities, estimators
  
Biasing                   Exponential Transform,
                          splitting/roulette. Automatisation of
                          biasing.
  
Time dependant transport  for neutrons.
  
Perturbation              Density, concentration of isotopes,
                          partial cross-sections.
  
Coupled particle          (neutron, gamma), (electron, positron,
transport                 gamma)
  
Qualification             Shielding (SINBAD benchmarks),
                          criticality (ICSBEP benchmarks)
  
------------------------------------------------------------------
Estimated physical quantities Type of estimator
  
                          volume            surface           point
Total flux                Track length        yes              yes
                          and collision
  
Integrated flux           Track length        yes              yes
per energy group          and collision
and time interval
  
Integrated flux           Track length        yes              yes
per energy group and      and collision
angular mesh
  
Integrated flux per       Track length        yes              yes
energy group              and collision
  
Total current                                 yes
  
Integrated current                            yes
per energy group and
time interval
  
Integrated current                            yes
per energy group and
angular mesh
  
Integrated flux per                           yes
energy group
  
Reaction rate on          Track length                         yes
whole energy range        and collision
  
Reaction rate per         Track length                         yes
energy group and          collision
time interval
  
Reaction rateper           Track length                         yes
energy group              collision
    
Deposited energy          collision
  
Equivalent dose rate      Track length        yes              yes
                          collision
  
Gamma production             yes
  
Multiplication factor     yes (kstep,
                        kcoll, ktrack, kij)
  
Eigen value of a             yes
criticality
configuration
  
Cross section                yes
(partial or total)
perturbations
  
Density or                   yes
concentration
perturbation
  
Data libraries distributed with the TRIPOLI-4:
- ENDFB6R4: neutron, gamma data library
- ENDL: gamma data library
- JEF2: neutron, gamma data library
- Mott-Rutherford: electron, positron cross-section library
- Qfission: energy release during fission library

TRIPOLI-4.4 does not contain the source programs.
  
New features available in TRIPOLI-4 version 4:
1. New biasing features: It is possible to store and re-use importance maps.
Biasing with a plane or spherical surface has been added (cylindrical was already available).
  
2. Neutron collision in multigroup homogenized mode: anisotropy up to the order 3 in the Legendre polynomial expansion (P3).
  
3. Display of the collision sites.
  
4. ENDF format evaluations: Mixed representation of the anisotropy from file 4 : Legendre format used at low energy and tabulated probability distributions at high energy (eg O16 from ENDFB6R8).
cf ENDF-102 Data formats and procedures for the evaluated nuclear data file ENDF-6. 07/1990, revised  04/2001. pages 4.3 to 4.5.
  
5. Computation of the gamma source produced by neutrons.
  
6. Output format for all results: the -a execution option allows even zero results to be displayed in the output.
Although the standard deviation is infinite in this case, for reason of compatibility with the rest of the code the output file gives also a zero value for the standard deviation.
  
7. Verbose level for output warnings: the code now gives only the most important information to the user. The -v option allows the warnings, the -D option gives the same verbose level as previous versions.
  
8. Photons reactions rates: In the RESPONSES command, interaction code 100 (coherent scattering), 101 (incoherent scattering), 102 (photoelectric effect), 103 (pair production) and 106 (total photon) are now available.
  
9. XML format output : In the SIMULATION command, the "XML_EXPORT" keyword allows the user to get an XML format output file. Any post-processing tool that can cope with XML format may be used to process this file.
  
10. ENDF format evaluations:
- By default use of evaluations produced by Njoy99. (version 81).
- It is possible to use jeff3.1, endfb7 and jendl3.3 evaluations:
    - the maximum order of Legendre polynomials is no longer limited to 21.
    - ENDF format 2D interpolation "unit-base" (file 6) is now supported.
  
11. Combinatorial geometry checks: It is now possible to choose the number of points for the non-overlaping tests of combinatorial volumes. The keyword is "TEST_GENERATED_POINTS n" (200 by default).
The keyword may be written:
- only once, at the beginning (after the TITLE keyword)
- or as many times as necessary in the GEOMETRY command, just before a VOLU keyword (for each combinatorial volume, the number of generated points refers to the last TEST_GENERATED_POINTS keyword).
  
12. Green's functions files.
  
13. Neutronics-shielding coupling.
  
14. Responses, scores, biasing names: It is possible to give names (instead of giving a number) to responses and scores. It is necessary to give names to responses, scores and biasings for neutronics-shielding coupled simulations.
  
15. Units: The -u execution option allows the code to output scores with their units.

4. METHODS

The geometry package allows the user to describe a three dimensional configuration by means of surfaces (as in the MCNP code) and also through predefined shapes combine with operators (union, intersection, subtraction...). It is also possible to repeat a pattern to built a network of networks.
  
TRIPOLI-4 can use four different types of cross-sections representation:
  
- full pointwise representation of cross-sections produced by NJOY processing code system. The cross-section files are converted into the XDR portable binary format,
- full self-shielded, homogenised multigroup cross-sections produced by the CEA lattice code APOLLO-2,
- multigroup cross-sections with probability-tables representation,
- ENDL cross sections.
  
Neutron and photon transport is governed by the Boltzmann equation. The code resolves this equation by the Monte Carlo method. This requires a random generator: TRIPOLI4 uses drand48 in non-parallel calculations and gfsr for parallel calculations. The calculation is carried out by division into several batches of particles, each batch containing an equal number of source particles.
Within a batch, the code monitors the particles in the following manner:
  
1)  The source particles are first generated by random selection according to the distribution supplied by the user (in space, energy, angle and time).
  
2)  Each particle is monitored individually:
a.  Between two impacts the trajectory is a straight line (since they are neutral particles). The distance between two impacts depends on the total cross-section of the medium.
  
b.  When an impact occurs, sampling concerns the impacted isotope (as a function of the concentration), then the type of interaction (as a function of the isotope) and finally the energy and direction after impact (as a function of the interaction and initial energy).
The mean results for each quantity required (based on the number of source particles per batch) are calculated over all the batches, each of which can be considered to be a sample. The final scores are obtained by calculating the average for the number of batches making up the total results. Standard deviation can then be calculated for the final values. If the number of batches is low and the central limit theorem does not apply, the code can use suitable bootstrap techniques.
  
If there is high attenuation, biasing techniques must be used to avoid excessive calculation times. In this case, the code performs an exponential transformation. (An importance factor is assigned to each point of phase space so that biased cross-sections can be used).
  
Several biasing techniques are implemented in TRIPOLI-4: exponential biasing scheme, quota sampling and collision biasing. The biasing is automatised from a Dijkstra algorithm.
  
The communication library has been written to achieve message passing between the different processes involved in the simulation. This library only cares of data that are exchange between processes while the parallelism library deals with actions that must be achieved by the processes.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM:  None noted.

6. TYPICAL RUNNING TIME

Currently, 10s up to 100s of millions of particle histories are simulated.

It depends on the number of simulated particles histories.

7. UNUSUAL FEATURES

User friendly input data and efficient automatic biasing techniques.
Versatile and robust parallel operation mode, for heterogeneous network of workstations, or massively parallel machines. TRIPOLI-4 is supported by a range of graphics and algorithmic productivity tools which means that checking for geometry and input deck errors is easy. As for the qualification, TRIPOLI-4 benefits from an extensive range of benchmarks and comparisons with real measurements, and is therefore qualified for R&D, teaching as well as industrial use.

GALILEE 2.0 libraries included in a TRIPOLI-4 specific format:
- JEFF31
- FENDL21
- JENDL33
- ENDFB7R0
- EPDL97
NJOY-99.259 and CALENDF-2005 were used in GALILEE 2.0.
The neutron cross-sections are available for the following nuclear evaluations: JEFF-3.1, ENDF/B-VII.0, JENDL-3.3, FENDL-2.1.
The cross-sections and probability tables are given at 294 K.
The bound nuclei cross-sections are given at every temperature available from the evaluation.
The gamma cross-sections are all given from the EPDL-97 evaluation.

10. REFERENCES

References concerning theory and functionalities:
- J. P. Both, A. Mazzolo, O. Petit, Y. Peneliau, B. Roesslinger:
User Manual for version 4.3 of the TRIPOLI-4 Monte Carlo method particle transport computer code, CEA-Report : CEA-R-6044, DTI, CEA/Saclay, France, 2003
- J.P. Both, H. Derriennic, B. Morillon, J.C. Nimal:
"A Survey of TRIPOLI-4", Proceedings of the 8th International Conference on Radiation Shielding, Arlington, Texas, USA, 24-28 avril 1994, pp.  373-380.
- B. Morillon:
"Methode de Monte Carlo non analogue - Application a la simulation des neutrons", Note CEA-N-2805, CEA/Saclay, janvier 1996.
- J.P. Both, Y.K. Lee:
"Computations of Homogenised Multigroup Cross Sections with the Monte Carlo Code TRIPOLI 4", Proceedings SARATOGA 1997, JIC MM &SNA, Saratoga Springs, New York, USA, october, 1997, p. 439.
- Y. Peneliau, J.P. Both:
"Parallelization of the Monte Carlo Code TRIPOLI-4", Mathematical and Computation, Reactor Physics and Environmental Analysis in Nuclear Applications, Madrid, Spain, Sept. 1999, p. 412.
- J. P. Both:
Treatment of Cross Section Uncertainties in the Transport Monte Carlo Code TRIPOLI-4, ICRS'9, Tsukuba, Ibaraki, Japan, october 17-22, 1999, Journal of Nuclear Science and Technology, Supplement 1, pp. 420-42, March 2000, pp. 420-426.
- Y. Peneliau:
"Electron Photon Shower Simulation TRIPOLI-4 in Monte Carlo Code", Advanced Monte Carlo for Radiation Physics, Particle Transport Simulation and Applications, Lisbon, Portugal, Oct. 2000.
- J. P. Both, Y.K. Lee, A. Mazzolo, O. Petit, Y. Peneliau, B. Roesslinger, M. Soldevila:
TRIPOLI-4 - A Three Dimensional Polykinetic Particle Transport Monte Carlo Code, SNA'2003, Paris Sept. 2003.
  
References concerning qualification:  
- Y.K. Lee, G. Neron, J.P. Both, Y. Peneliau, C. Diop:
"Validation of Monte Carlo Code TRIPOLI-4 with PWR Critical Lattices by using JEF 2.2 and ENDF/B-VI Evaluations". JIC MM &SNA, Saratoga Springs, New York, USA, October, 1997, p. 253.
- Y.K. Lee, S.H. Zheng, G. Neron, J.P. Both, Y. Peneliau, C. Diop:
"ICNC'9, Cristal, Criticality Safety Package Validation : Tripoli-4 Monte Carlo Code, JEF2.2 Library and ICSBEP Experiments", Sixth International Conference on Nuclear Criticality Safety.  Versailles, France, 20-24 September 1999.,
- Y. K. Lee:
"Analysis of the NRC PCA Pressure Vessel Dosimetry Benchmark Using TRIPOLI-4.3 Monte Carlo Code and ENDF/B-VI, JEF-2.2 and IRDF-90 Libraries, Nuclear Mathematical and Computational Science", Gatlinburg, Tennessee, USA, April 6-11 2003.
- E. Gagnier, Y. K. Lee, L. Aguiar, N. Vedrenne:
Validation of the 3D Transport Monte Carlo Code TRIPOLI-4.3 for moderated and unmoderated metallic fissile media configurations with Jef-2.2 and ENDF/B6.r4 cross section evaluations ; Y. K. Lee, Analysis of the LEU-COMP-THERM-049 Maracas Critical Configurations Using TRIPOLI-4.3 3D Lattices Geometry and JEFF-3.0 Library, ICNC'2003, Tokai-Mura, October 2003.
- Y. K. Lee, Analysis of the LEU-COMP-THERM-049 Maracas Critical Configurations Using TRIPOLI-4.3 3D Lattices Geometry and JEFF-3.0 Library.

- J.-P. Both, A. Mazzolo, Y. Peneliau, O. Petit and B. Roesslinger:
User Manual for Version 4.3 of the TRIPOLI-4 Monte-Carlo Method Particle
Transport Computer Code
ISSN 0429 - 3460  Rapport CEA-R-6044 (November 2003)
- J.-P. Both, A. Mazzolo, Y. Peneliau, O. Petit and B. Roesslinger:
Notice d'Utilisation du Code TRIPOLI-4 Version 4.3: Code de Transport de
Particules par la Methode de Monte Carlo
ISSN 0429 - 3460  Rapport CEA-R-6043 (Novembre 2003)

- O. Petit, F-X. Hugot, Y-K. Lee, C. Jouanne, A. Mazzolo:
TRIPOLI-4 VERSION 4 USER GUIDE, Rapport CEA-R-6169 (January 2008)
- O. Petit, F-X. Hugot, Y-K. Lee, C. Jouanne, A. Mazzolo:
TRIPOLI-4 VERSION 4 MANUEL DE L'UTILISATEUR, Rapport CEA-R-6169 (Janvier 2008)
- J-C. Sublet:
JEFF-3.1, ENDF/B-VII and JENDL-3.3 Critical Assemblies Benchmarking with the
Monte Carlo Code TRIPOLI, IEEE Transactions on Nuclear Science, Vol.55 No.1,
February 2008
- C. Jouanne and J-C. Sublet:
TRIPOLI-4.4 JEFF-3.1 Based Librarires, Rapport CEA-R-6125 (Novembre 2006)

11. HARDWARE REQUIREMENTS

TRIPOLI-4 is operable on workstations and on PC's running UNIX or LINUX.

TRIPOLI-4.4 requires 1.5Gbytes of disk space. The associated libraries require 14 Gbytes of disk space.

13. SOFTWARE REQUIREMENTS

   
TRIPOLI-4 runs on workstation networks (SUN, IBM, HP, Digital, Silicon Graphics) and on massively parallel machines (Cray, Compaq).

TRIPOLI-4.3.3 contains the source programs.

TRIPOLI-4.4: No sources are included.
The binaries have been produced and tested on the following platforms:
- Solaris-sparc (5.7, 5.8 ou 5.9)
- linux-intel (2.4.xx, 2.6.xx)
- osf1 (V5.1)
- aix (5.1)
  
Depending on the operating system, the exact version of the system libraries used in Tripoli4 can be available or not. In case, there are some missing libraries, the system manager will be able to install them. The ldd command used on the binary (in CODE/bin//static-tripoli4-4.4) can help to identify if there are missing libraries. The environment variable LD_LIBRARY_PATH can also be used to specify directories containing the otherwise missing libraries.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

TRIPOLI-4 architecture is based on five libraries: a geometry library (C language), a communication library (C++), a parallelisation library (C++), a memory management library (C++), a cross-section (ENDF and ENDL) reading library (Fortran from NJOY I/O routines) and a simulation library (C++).
  
Fortran to C converter (F2C) is required for the Linux version. This software can be downloaded from the NETLIB site www.netlib.org
  
Any pointwise cross-section data in ENDF/B format may be used: JEF2, ENDF/B-VI, JEFF3, ENDF/B-VII, JENDL3.3 etc. As for thermal neutrons, both free gas and S(alpha, beta) models are available.

15. NAME AND ESTABLISHMENT OF AUTHORS

Developed by :
    J. P. Both, A. Mazzolo, O. Petit, Y. Peneliau, B. Roesslinger,
    Commissariat a l'energie atomique (CEA)
    DM2S/SERMA/LEPP CEA/SACLAY
    91191 Gif sur Yvette Cedex
    France

CODE/  Sources, objects, binaries and makefiles
ENDFB6R4/   ENDF nuclear data libraries [neutrons, gammas]
ENDL/   ENDL nuclear data libraries [gammas]
Env-4.3/   Director and dictionary files
JEF2/   ENDF nuclear data libraries [neutrons, gammas]
Mott_rutherford/   Mott cross-section libraries [electrons, positrons]
Qfission/   Libraries of energy release during fission
T4site-4.3/   HTML files and documentation
--

Binaries
ENDFB6R4/   ENDF nuclear data libraries [neutrons, gammas]
ENDL/   ENDL nuclear data libraries [gammas]
ENV/   Directory and dictionary files
JEF2/   ENDF nuclear data libraries [neutrons, gammas]
Mott_rutherford/   Mott cross-section libraries [electrons, positrons]
Qfission/   Libraries of energy release during fission
Examples of some of the new fonctionalities of Tripoli4.4
TRIPOLI-4.3 Criticality sample calculation cases
Installation procedures and execution call
Script files
Atomic mass adjustment
English and French documentation
GALILEE 2.0 Processed libraries in a TRIPOLI-4 specific format:
JEFF31, FENDL21, JENDL33, ENDFB7R0, EPDL97