Multi-neutron Simulation

This page explains step-by-step procedure on how to simulate multi-neutron detection with NeuLAND. The working directory for the macros is R3BRoot/macros/r3b/land/. You need to adjust the path and file names according to the environment on your machine. The input ASCII files can be downloaded at the bottom of this page. After unpacking the archives, put the *.dat files to your R3BRoot/input/ directory.

1. Monte Carlo Transport

. ./
cd [R3BROOT_SOURCE_DIR]/macros/r3b/land
root -l
[..] .L r3blandsim.C
[..] r3blandsim(nNeutrons, 10000, 600, 500)
[..] .q

where 600 is the beam energy in AMeV and 500 is relative energy of fragment and neutrons in keV. The simulation has to be repeated 4 times for nNeutrons = 1, 2, 3 and 4.

2. Digitizer, Cluster Finder

This stage converts NeuLAND MC Points into Digi's (detector-like signals) and finds clusters of charged particles in the detector.

root -l
[..] .L preCalibr.C
[..] preCalibr(nNeutrons, 10000, 600, 500)
[..] .q

3. Calculation of Cuts on Energy Deposit and Number of Clusters

root -l
[..] .L calibr.C
[..] calibr_2D(600, 500, 0.07)
[..] .q

where 0.07 is a slope coefficient of the linear cuts (default value). This macro reads all 4 input files and has to be executed only once.
It will produce output text file with the parameters needed by the neutron tracking task.
The graphical output should be similar to the example image at the bottom of this page.

4. Reconstruction

This stage makes the actual event class identification and calculates energy of incident neutrons.

root -l
[..] .L r3blandreco.C
[..] r3blandreco(nNeutrons, 10000, 600, 500)
[..] .q

The macro eff.C can be used to see the output of calculated efficiencies of multi-neutron detection.

Input Files

132Sn, Ebeam=200AMeV, Erel=100keV
132Sn, Ebeam=600AMeV, Erel=100keV
132Sn, Ebeam=1000AMeV, Erel=100keV
132Sn, Ebeam=200AMeV, Erel=500keV
132Sn, Ebeam=600AMeV, Erel=500keV
132Sn, Ebeam=1000AMeV, Erel=500keV