LBNF Beam Simulation Group

The G4LBNF Software

Downloading the G4LBNF code

G4LBNE software is maintained in a git repository: associated with this redmine project. You may clone this repository anonymously and without authentication. In order to push commits back you must be authenticated. See About this redmine for details on authentication.

Authenticated clone (allows push):

$ git clone ssh://

Only those who have been set as developers of this redmine repository will be able to do an authenticated clone. Please contact the managers of this redmine (currently Laura Fields and Zarko Pavlovic) if you need access. In the meantime, you can do an anonymous clone (no push):

$ git clone

For help with git see Git Help. To check out a fixed release of g4lbne (which is recommended) into a directory with the name of the tag, you can do:

$ git clone ssh:// <tag_name>
$ cd <tag_name>
$ git checkout <tag_name>

You can see a list of available tags by doing:
$ git tag

Building G4LBNE at Fermilab

See the README.txt file

Also older instructions here: Install-G4-v4-10

Installing and Setting up G4LBNF on Offsite Machines

See the Installation topic information on how to install G4LBNF and its dependencies.

Running G4LBNF

  • see the README.txt file from the repository for information on running g4lbne.
    (setup file in README.txt --> (not
  • Configuring a g4lbne run with a macro file that contains Geant User Interface cards Input
  • Documentation of the G4LBNF neutrino numi-style ntuple and dk2nu ntuples
  • Documentation on particle tracking plane output

Versions of G4LBNE to use

Version information is available in the ReleaseNotes.txt file. In general, you should use the most recent release. Administrators wanting to create a new release should consult the release instructions.

Some versions of G4LBNF are installed in cvmfs for use on the Open Science Grid. Instructions for installing on cvmfs: Installing G4LBNF on CVMFS

Visuallizing geometries in g4lbne v3

See: Visualization.

On the use of Geantinos

Geantino are perfectly sterile, neutral particles that go through the geometry without invoking any of the physics processes. They are used to study accurately the geometry by recording the volume boundary crossing, step by step. Addition functionality in LBNESteppingAction has been written to study simple ASCII tables that contain this information, thereby allowing a systematic way of cross-checking the geometry once a new volume has been created. Additional info in Geantinos

FLUKA Interface

The modelling of the hadronic physics in Geant4 relies both on the High Energy Physics Standard Model, QCD in particular, and on complex phenomenology, which itself is based on accumulated data over decades. Consequently, our neutrino flux prediction are model dependant. Similar Monte-Carlo generator have been written, such as MARS and FLUKA. A comparison of our neutrino beam performance, estimated via the Geant4 Physics List, and the pion flux estimated by FLUKA is possible. For assumptions and use, see FlukaInterface

G4LBNE weights

As many such package, tracing particles that a low probability of producing what we want - neutrinos pointing at the detectors - G4lbne is "weighted". By this, we mean that to each neutrino. For a brief description of the pro/cons of this technique, and how to avoid the so-called importance weight, see Weights.

PPFX project

Project to understand production models and estimate systematic uncertainties using PPFX, see PPFX project

Estimating CP Sensitivity

Instructions on using the DUNE CDR GLoBES setup to study physics sensitivities of different beam options -- See Studying Physics Sensitivity of Different Beam Options

Beam Optimization

Documentation of the software used by the beam optimization task force is available at Beam Optimization

Studying Alignment Uncertainties

See Shifting Alignment Parameters in G4LBNF

Documentation on Beam Design

Beam Documentation