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System requirements and installation instructions can be found here. It is recommended to consult this page if you are unsure which package to download.

Latest FLUKA version: 4-3.1, released on:
Release highlights:

FLUKA version: 4-3.1, released on: 2022-12-15

Release highlights:

Novelties of FLUKA 4-3.1 are displayed in italics.


  • A new point-wise treatment has been included for the interactions of low-energy neutrons (below 20 MeV), controlled by the new LOW-PWXS card. The download of at least one additional package is required, as detailed here.

  • The code is now aligned with DPMJET v19.3.2, fixing spurious features in
    kaon spectra from nucleus-nucleus collisions at energies of ~10 GeV/n.

  • Scoring of athermal-recombination-corrected displacements per atom (arc-DPA) has been added, requiring two new user-specified parameters, as detailed in the MAT-PROP card documentation. Generalized particle DPA-NRES (#245) has been deprecated and replaced by the Norgett-Robinson-Torrens DPA-NRT.

  • The emission of synchrotron radiation photons along charged particle steps, in vacuum regions subject to a magnetic field, has been implemented and is requested via the SYRASTEP card.

  • Mass distribution of 226Ra fission fragments was corrected, addressing this forum post

  • Reworked sampling of the target nucleus thermal motion for the elastic scattering of thermal neutrons, correcting an artifact that led to neutron fluxes slightly skewed towards energies lower than kT, affecting in particular light target nuclei.

  • The parametrized reaction cross section of protons on deuterium below 5.5 MeV was refined to better reproduce experimental data available from EXFOR for the (p,g) and (p,n) channels, removing an unphysical rise below few MeV.


  • The new DETGEB card allows the user to apply a Gaussian broadening to energy deposition spectra scored with the DETECT card.

  • The maximum number of regions of interest (ROI) in voxel geometries has been increased from 100 to 400.

  • In the source_newgen.f user routine, sampling from a spectrum file (energy, intensity) was added.

  • The code manual has been recast in restructured text format, providing the user with three consistent versions: text, pdf, and html. The latter is accessible at .

  • Nuclear recoils with the same atomic and mass number as the target isotopeĀ  now contribute to RESNUCLEi scoring only when reaching a different geometry region.

  • Kshort and Klong scorings now also include the respective contribution of K0 and K0bar, and viceversa.

  • A simplified version of mgdraw (mgdraw_empty.f) is now offered for convenience, in addition to the original mgdraw.f.

Several bugs were fixed (see release notes for a complete list).

Binary libraries for GNU/Linux:
Download gfortran 7, 64 bits (.tgz)
Download gfortran 7, 64 bits (.rpm)
Download gfortran 7, 64 bits (.deb)
Download gfortran 9, 64 bits (.tgz)
Download gfortran 9, 64 bits (.rpm)
Download gfortran 9, 64 bits (.deb)
Binary libraries for macOS:
Download gfortran 10, 64 bits (.tgz)
Download gfortran 11, 64 bits - ARM (.tgz)
Source code*:
Download (.tgz)
Download (.rpm)