FluxReader

The FluxReader code allows reading gSimple, Dk2Nu, or BooNE files direclty into LArSoft. For each neutrino ray, an MCTruth dataproduct is created with associated MCFlux. The usual LArSoft chain involves starting with a neutrino event generator, which reads in gSimple flux files and saves neutrino interactions in the LArSoft art::Event. In this way though, neutrinos that do not interact are lost and one cannot calculate, for example, the neutrino flux. FluxReader instead reads in gSimple files direclty and saves all the neutrinos to the LArSoft art::Event. There is no neutrino event generator involved in this case. Note that in this case, each MCTruth product does not represent a neutrino interaction, but just a neutrino ray.

This code is available since sbndcode v09_25_00.

How to Run

A fcl driver for SBND is run_fluxreader_sbnd.fcl. You need to provide gSimple flux files as input. For example:

lar -c run_fluxreader_sbnd.fcl -S /pnfs/sbnd/resilient/users/mdeltutt/Filelists/gsimple_flux_configH-v1_10files.list

will run FluxReader with 10 input gSimple files listed in gsimple_flux_configH-v1_10files.list.

run_fluxreader_sbnd runs the following:

• FluxReader (art::Source): reads each neutrino in the gSimple file, creates MCTruth, MCFlux (and Dk2Nu and NuChoice) dataproducts and places them in an art::Event
• FluxGeoFilter (art::Filter): filters events based on the neutrino position. It moves along the neutrino direction, and only keeps events if the neutrino intersects at least one of the specified volumes. The default volume is volTPCActive.
• FluxReaderAne (art::Analyzer): analyzer that creates an output TTree with all neutrinos hitting a customizable area. Currenlty set to the SBND front face.

If you’d like to run with the BooNE files as input, use

lar -c run_fluxreader_boone_sbnd.fcl -S /pnfs/sbnd/resilient/users/mdeltutt/Filelists/boonetuple_configH_small.list