RSICC Home Page MCNP6.2

RSICC CODE PACKAGE CCC-850

                                    MCNP® and Monte Carlo N-Particle® are registered trademarks owned by Los Alamos National Security, LLC, manager and operator of Los Alamos National Laboratory. Any third party use of such registered marks should be properly attributed to Los Alamos National Security, LLC, including the use of the ® designation as appropriate. Please note that trademarks are adjectives and should not be pluralized or used as a noun or a verb in any context for any reason. Any questions regarding licensing, proper use, and/or proper attribution of Los Alamos National Security, LLC marks should be directed to trademarks@lanl.gov.

Export control regulations restrict the distribution of Fortran source code. If restrictions apply, RSICC will send the executable-only version.

            NAME AND TITLE

MCNP6.2:         Monte Carlo N–Particle® Transport Code System Version 6.2

 

 

1.         MCNP6.2:        Monte Carlo N–Particle® Transport Code System Version 6.2.

RELATED DATA LIBRARIES 

MCNPDATA:          Standard Neutron, Photoatomic, Photonuclear, Electron, and Proton Data.

AUXILIARY PROGRAMS included in the distribution

MAKXSF:               Prepares MCNP cross-section libraries; now with Doppler broadening.

GRIDCONV:           Converts output of mesh and radiography tallies to input for external graphics programs.

UM_CONVERT:              The um_convert (unstructured mesh convertor) program is a command-line utility program that takes the information in the Abaqus input file and processes it with the UM input processing routines from REGL to produce the internal data structures that MCNP needs.

UM_POST_OP:               Allows the user to write error histograms to an output file for all of the edits in the eeout file for which errors were requested. Prepares MCNPX Cross-Section Libraries.

Whisper:      Software for sensitivity-uncertainty-based nuclear criticality safety Validation.

ISC:                  Intrinsic Source Constructor is a software library and associated data files to construct radioactive source descriptions given a set of material isotopics.

2.         CONTRIBUTOR

Los Alamos National Laboratory, Los Alamos, New Mexico.

3.         CODING LANGUAGE AND COMPUTER      

Package ID: C00850MNYCP00:    

Fortran 90, C,C++ source code and executables for Windows PCs, Linux PCs, and MacOSX.

Package ID: C00850MNYCP01:   

Executables only (no source code) for Windows PCs, Linux PCs, Macintosh with MacOSX.

 

Export control regulations restrict the distribution of Fortran source code. If restrictions apply, RSICC will send the executable-only version. Please note that included MCNP6.2 executables run only on the machines listed.

4.         NATURE OF PROBLEM SOLVED

Monte Carlo N-Particle® or MCNP® is a general-purpose Monte Carlo radiation-transport code designed to track many particle types over broad ranges of energies. MCNP version 6.2 follows the MCNP6.1.1 beta version and has been released in order to provide the radiation transport community with the latest feature developments and bug fixes for MCNP. Since the last release of MCNP® , major work has been conducted to improve the code base, add features, and provide tools to facilitate ease of use of MCNP6.2 as well as the analysis of results. These release notes serve as a general guide for the new/improved physics, source, data, tallies, unstructured mesh, code enhancements and tools. This release of MCNP version 6.2 contains 39 new features in addition to 172 bug fixes and code enhancements.

5.         METHOD OF SOLUTION

MCNP version 6.2 has the same or better performance than MCNP6.1.1, demonstrating 1.5 to 2 times faster than MCNP6.1 for Nuclear Criticality Safety (NCS) applications, and is slightly faster than previous versions of MCNP5. For NCS applications, significant improvements were made in the energy and cross-section treatment for neutron calculations, the parallel threading performance, and efficient treatment of the checking for the multitude of options available in MCNP® . Improvements include:

Physics:

• Improved correlated prompt secondary particle production (CGM)

• Exact line emission treatment for delayed gamma production

• Decay emission treatment

• Charged particle delta-ray production


Source:

• Spontaneous decay and activation improvements

• Improved cosmic-ray source:

o Inclusion of heavy ions

o Updated solar modulation data

• Improved background source:

o Updated cosmic and terrestrial background data file

o Automatic elevation and data scaling


Data:

• Revised nuclear data for hydrogen

• SiO2 S(α ,β) thermal scattering data updated

• Zr-Hydride S(α ,β) thermal scattering data updated at 1200K

• New listing of available ACE data

• New default XSDIR file for MCNP® version 6.2

• New electron-photon relaxation library (EPRDATA14)

• Large-angle and total electron elastic cross section data

• Improved decay library data file, increasing radionuclides from 979 to 3475


Tallies

• Built-in physics-based neutron and photon response functions

• Improved first-fission special tally option

• New collision-based cell-flag tally option

• Surface flux tally improvements


Unstructured Mesh:

• Improved tracking of charged particles on unstructured mesh

• Creation of new UM input file type (MCNPUM)

• Selection of overlap model by part

• Surface flux tally improvements

• Ability to specify flux multipliers on the UM edits

• Ability to read and handle multiple UM’s in separate mesh universes


Code Enhancements:

• Filenames used by MCNP® may now be up to 256 characters in length

• Permit line lengths up to 128 chars in MCNP input files and xsdir files

• Extend command line length to permit up to 4096 characters

• Remove limit on boundary-list entries for cell descriptions

• The number of point detectors allowed increased from 100 to 1000s



Tools:

• Whisper – software for sensitivity-uncertainty-based nuclear criticality safety validation

• The MCNPTools package

• Intrinsic Source Constructor (ISC)

• The UM_CONVERT utility program

• Improved UM_POST_OP functionality


6.         RESTRICTIONS OR LIMITATIONS

There are 33 known issues or limitations, please see listed manual MCNP® Version 6.2 Release Notes Appendix for more information.

7.         TYPICAL RUNNING TIME

Problem dependent.

8.         COMPUTER HARDWARE REQUIREMENTS

MCNP6.2 will operate on most systems.

9.         COMPUTER SOFTWARE REQUIREMENTS

MCNP6.2 runs on under Linux, MacOS, and Windows, including Cygwin. Current supported compilers include GFORTRAN 4.8.5-6.4.0, Intel 15.0.5-18.0 and PGI (Linux Only) 14.10-16.10. Currently only Intel Compilers are supported. New compiler versions are often released a few times a year, and some of them may not compile MCNP62. Check the MCNP FAQ (https://mcnp.lanl.gov/mcnp_faq.shtml) for more information.

 

10.        REFERENCES

Included documentation in electronic format to be extracted to your hard drive:

MCNP® USER’S MANUAL Code Version 6.2 , Los Alamos National Laboratory report LA-UR-17-29981.

MCNP® Version 6.2 Release Notes , Los Alamos National Laboratory report LA-UR-17-29981.

Many more reference documents on MCNP® are included in the MCNP® REFS directory of this distribution.

directory of this distribution.

11.        CONTENTS OF CODE PACKAGE

The MCNP6.2 package is distributed on 3 DVDs that can be read on Windows, Linux or MacOS systems.

· Disc 1 of C00850MNYCP00 contains MCNP6.2 source code, pre-compiled executables and reference documents.

· Disc 1 of C00850MNYCP01 contains MCNP6.2 pre-compiled executables and reference documents.

· Discs 2 and 3 of both packages contain the same ENDF/B-VII.1 data.


 

12.        DATE OF ABSTRACT

March 2018.

KEYWORDS:       COMPLEX GEOMETRY; COUPLED; CROSS SECTIONS; ELECTRON; GAMMA-RAY; MONTE CARLO; NEUTRON

 

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            NAME AND TITLE

MCNP6.2-EXE:         Monte Carlo N–Particle® Transport Code System Version 6.2-EXE

 

 

1.         MCNP6.2-EXE:        Monte Carlo N–Particle® Transport Code System Version 6.2.

RELATED DATA LIBRARIES 

MCNPDATA:          Standard Neutron, Photoatomic, Photonuclear, Electron, and Proton Data.

AUXILIARY PROGRAMS included in the distribution

MAKXSF:               Prepares MCNP cross-section libraries; now with Doppler broadening.

GRIDCONV:           Converts output of mesh and radiography tallies to input for external graphics programs.

UM_CONVERT:              The um_convert (unstructured mesh convertor) program is a command-line utility program that takes the information in the Abaqus input file and processes it with the UM input processing routines from REGL to produce the internal data structures that MCNP needs.

UM_POST_OP:               Allows the user to write error histograms to an output file for all of the edits in the eeout file for which errors were requested. Prepares MCNPX Cross-Section Libraries.

Whisper:      Software for sensitivity-uncertainty-based nuclear criticality safety Validation.

ISC:                  Intrinsic Source Constructor is a software library and associated data files to construct radioactive source descriptions given a set of material isotopics.

2.         CONTRIBUTOR

Los Alamos National Laboratory, Los Alamos, New Mexico.

3.         CODING LANGUAGE AND COMPUTER      

Package ID: C00850MNYCP00:    

Fortran 90, C,C++ source code and executables for Windows PCs, Linux PCs, and MacOSX.

Package ID: C00850MNYCP01:   

Executables only (no source code) for Windows PCs, Linux PCs, Macintosh with MacOSX.

 

Export control regulations restrict the distribution of Fortran source code. If restrictions apply, RSICC will send the executable-only version. Please note that included MCNP6.2 executables run only on the machines listed.

4.         NATURE OF PROBLEM SOLVED

Monte Carlo N-Particle® or MCNP® is a general-purpose Monte Carlo radiation-transport code designed to track many particle types over broad ranges of energies. MCNP version 6.2 follows the MCNP6.1.1 beta version and has been released in order to provide the radiation transport community with the latest feature developments and bug fixes for MCNP. Since the last release of MCNP® , major work has been conducted to improve the code base, add features, and provide tools to facilitate ease of use of MCNP6.2 as well as the analysis of results. These release notes serve as a general guide for the new/improved physics, source, data, tallies, unstructured mesh, code enhancements and tools. This release of MCNP version 6.2 contains 39 new features in addition to 172 bug fixes and code enhancements.

5.         METHOD OF SOLUTION

MCNP version 6.2 has the same or better performance than MCNP6.1.1, demonstrating 1.5 to 2 times faster than MCNP6.1 for Nuclear Criticality Safety (NCS) applications, and is slightly faster than previous versions of MCNP5. For NCS applications, significant improvements were made in the energy and cross-section treatment for neutron calculations, the parallel threading performance, and efficient treatment of the checking for the multitude of options available in MCNP® . Improvements include:

Physics:

• Improved correlated prompt secondary particle production (CGM)

• Exact line emission treatment for delayed gamma production

• Decay emission treatment

• Charged particle delta-ray production


Source:

• Spontaneous decay and activation improvements

• Improved cosmic-ray source:

o Inclusion of heavy ions

o Updated solar modulation data

• Improved background source:

o Updated cosmic and terrestrial background data file

o Automatic elevation and data scaling


Data:

• Revised nuclear data for hydrogen

• SiO2 S(α ,β) thermal scattering data updated

• Zr-Hydride S(α ,β) thermal scattering data updated at 1200K

• New listing of available ACE data

• New default XSDIR file for MCNP® version 6.2

• New electron-photon relaxation library (EPRDATA14)

• Large-angle and total electron elastic cross section data

• Improved decay library data file, increasing radionuclides from 979 to 3475


Tallies

• Built-in physics-based neutron and photon response functions

• Improved first-fission special tally option

• New collision-based cell-flag tally option

• Surface flux tally improvements


Unstructured Mesh:

• Improved tracking of charged particles on unstructured mesh

• Creation of new UM input file type (MCNPUM)

• Selection of overlap model by part

• Surface flux tally improvements

• Ability to specify flux multipliers on the UM edits

• Ability to read and handle multiple UM’s in separate mesh universes


Code Enhancements:

• Filenames used by MCNP® may now be up to 256 characters in length

• Permit line lengths up to 128 chars in MCNP input files and xsdir files

• Extend command line length to permit up to 4096 characters

• Remove limit on boundary-list entries for cell descriptions

• The number of point detectors allowed increased from 100 to 1000s



Tools:

• Whisper – software for sensitivity-uncertainty-based nuclear criticality safety validation

• The MCNPTools package

• Intrinsic Source Constructor (ISC)

• The UM_CONVERT utility program

• Improved UM_POST_OP functionality


6.         RESTRICTIONS OR LIMITATIONS

There are 33 known issues or limitations, please see listed manual MCNP® Version 6.2 Release Notes Appendix for more information.

7.         TYPICAL RUNNING TIME

Problem dependent.

8.         COMPUTER HARDWARE REQUIREMENTS

MCNP6.2 will operate on most systems.

9.         COMPUTER SOFTWARE REQUIREMENTS

MCNP6.2 runs on under Linux, MacOS, and Windows, including Cygwin. Current supported compilers include GFORTRAN 4.8.5-6.4.0, Intel 15.0.5-18.0 and PGI (Linux Only) 14.10-16.10. Currently only Intel Compilers are supported. New compiler versions are often released a few times a year, and some of them may not compile MCNP62. Check the MCNP FAQ (https://mcnp.lanl.gov/mcnp_faq.shtml) for more information.

 

10.        REFERENCES

Included documentation in electronic format to be extracted to your hard drive:

MCNP® USER’S MANUAL Code Version 6.2 , Los Alamos National Laboratory report LA-UR-17-29981.

MCNP® Version 6.2 Release Notes , Los Alamos National Laboratory report LA-UR-17-29981.

Many more reference documents on MCNP® are included in the MCNP® REFS directory of this distribution.

directory of this distribution.

11.        CONTENTS OF CODE PACKAGE

The MCNP6.2 package is distributed on 3 DVDs that can be read on Windows, Linux or MacOS systems.

· Disc 1 of C00850MNYCP00 contains MCNP6.2 source code, pre-compiled executables and reference documents.

· Disc 1 of C00850MNYCP01 contains MCNP6.2 pre-compiled executables and reference documents.

· Discs 2 and 3 of both packages contain the same ENDF/B-VII.1 data.


 

12.        DATE OF ABSTRACT

March 2018.

KEYWORDS:       COMPLEX GEOMETRY; COUPLED; CROSS SECTIONS; ELECTRON; GAMMA-RAY; MONTE CARLO; NEUTRON

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