Skip to content

Latest commit

 

History

History
236 lines (199 loc) · 8.83 KB

README.md

File metadata and controls

236 lines (199 loc) · 8.83 KB
Raw

warwick-legend

Legend muon background simulations

First attempt at creating a LEGEND Monte-Carlo simulation application, suitable for large production runs estimating Germanium-77 production in Germanium-76 crystals in different underground laboratories.

Should allow for two alternative experimental setups.

Requirements

Multi-threading operation and MPI capability

ROOT ntuple output

Biasing of neutron production by muons (physics bias), neutron population inside cryostant (geometry bias) and neutron capture reaction (Ge-77 production from n,gamma reaction)

Operate with command line input and Geant4 macro.

Macro commands for change of geometry, primary vertex generator and cross section bias factor (one each, neutron and muon)

CLI for number of threads, macro file, output file name (for production runs)

User Limits for run time optimization

How to Build/Develop

The project has the following requirements:

  • Linux/macOS system (only CentOS7, Catalina tested at present)
  • C++17 compatible compiler (GCC9, Xcode 11 tested at present)
  • CMake 3.12 or newer
  • Geant4 10.6 built with multithreading and gdml support
    • Qt or OpenGL/X11 driver support if you want to visualize the geometry/tracks/hits

It may be compiled using:

$ mkdir build && cd build
$ cmake ..
$ make

Testing is enabled by default via the BUILD_TESTING CMake argument and may be run after building by running

$ ctest

Run ctest --help for options to select tests and/or run with increased verbosity, e.g.

$ ctest -VV

to get verbose (including stdout) output from the setup and execution of the tests.

The resulting warwick-legend application may be run without arguments to start an interactive session. Otherwise run warwick-legend --help to see a list of options for batch mode running.

Support files for [clang-format](https://clang.llvm.org/docs/ClangFormat.html) and [clang-tidy](https://clang.llvm.org/extra/clang-tidy/) are provided to help automate formatting (following the Geant4 style) and static analysis respectively. No explicit setup is needed for autoformatting other than the relevant integration settings of your favoured editor/IDE (vim, emacs, vscode). To enable static analysis, ensure you have clang-tidy installed and run the build as:

$ mkdir build-tidy && cd build-tidy
$ cmake -DCMAKE_CXX_CLANG_TIDY="/path/to/clang-tidy" ..
$ make

The .clang-tidy file supplied in this project will be used, and suggestions for fixes will be emitted whilst building. At present, the -fix option is automatically apply the suggested change is not used to leave the decision up to the developer. The set of fixes applied are:

  • readability-*
  • modernize-*
  • performance-*

For a full listing of the wildcards, see the clang-tidy documentation.

Code Details

Cross section bias reference

M.H. Mendenhall and R.A. Weller, NIM A667 (2012) 38-43

Ntuple output columns

  • Hit data, one row per event
    • Edep
    • Time
    • Weight
    • Hit x location
    • Hit y location
    • Hit z location
  • Trajectory data, one row per event
    • PDG code
    • N entries in position containers
    • Vertex logical volume name code, see name map
    • Vertex x location
    • Vertex y location
    • Vertex z location
  • Trajectory data track step points, N rows, see N entries column above
    • x position
    • y position
    • z position

Vertex Name Map

Volume definitions in detector construction.

  • lookup["Cavern_log"] = 0;
  • lookup["Hall_log"] = 1;
  • lookup["Tank_log"] = 2;
  • lookup["Water_log"] = 3;
  • lookup["Cout_log"] = 4;
  • lookup["Cvac_log"] = 5;
  • lookup["Cinn_log"] = 6;
  • lookup["Lar_log"] = 7;
  • lookup["Lid_log"] = 8;
  • lookup["Bot_log"] = 9;
  • lookup["Copper_log"] = 10;
  • lookup["ULar_log"] = 11;
  • lookup["Ge_log"] = 12;
  • lookup["Pu_log"] = 13;
  • lookup["Membrane_log"] = 14;

Changes after the fork from the original

A lot has been added in my version of the fork. An output for the Ge77m veto has been added, more options to adjust the geometry via macros and several new primary generators.

Overview over the Macros

Runaction Macro

Macros regarding the output of the simulation

/WLGD/runaction/
  - WriteOutNeutronProductionInfo
  - WriteOutGeneralNeutronInfo
  - getIndividualGeDepositionInfo
  - getIndividualGdDepositionInfo

Event Macro

Macro to adjust the condition to save all events (1) or just the ones with Ge77 production (0)

/WLGD/event/
  - saveAllEvents (no: [0], yes: 1)

Generator Macro

Macros to controll the primary generator

/WLGD/generator/
  - depth
  - setMUSUNFile (path to file)
  - setGenerator (options: "MeiAndHume", "Musun", "Ge77m", "Ge77andGe77m", "ModeratorNeutrons", "ExternalNeutrons")

Detector Macro

Macros to controll the detector geometry

/WLGD/detector/
  - setPositionOfDetectors
  - setGeometry
  - exportGeometry
  - XeConc
  - He3Conc
  - Cryostat_Radius_Outer
  - Cryostat_Height
  - Without_Cupper_Tubes
  - With_Gd_Water
  - With_NeutronModerators (options: 0: [no moderators], 1: around re-entrance tubes, 2: in turbine mode, 3: in large hollow tube mode)
  - Which_Material (options: [BoratedPE], PolyEthylene, PMMA)
  - TurbineAndTube
    - Radius
    - Width
    - Height
    - zPosition
    - NPanels

Bias Macro

Macros to adjust the bias of the cross-sections

/WLGD/bias/
  - setNeutronBias
  - setMuonBias
  - setNeutronYieldBias

Step Macro

Macros to adjust whether additional output (additional to the Ge77 production) is recorded in the first place

/WLGD/step/
  - getDepositionInfo (multiplicity and energy deposition in the detectors)
  - getIndividualDepositionInfo (energy depositions in the whole cryostat)
  - AllowForLongTimeEmissionReadout (allow for energy depositions >1s after muon crossing to be recorded)

Example for Ge77 production by Radiogenic Neutron from the moderators:

/WLGD/detector/setGeometry baseline             # setting the geometry of the detector to the baseline design
/WLGD/event/saveAllEvents 0                     # only the Ge77 producing events are saved
/WLGD/detector/With_NeutronModerators 1         # using the moderator design with the tubes right around the re-entrance tubes
/WLGD/step/getDepositionInfo 1                  # save the information of multiplicity and total energy deposited in detectors
/run/initialize                                 
/WLGD/generator/setGenerator ModeratorNeutrons  # set the primary generator to the (Alpha,n) generator in the moderators
/run/beamOn 1000000

Example for Ge77 production using Gd water and Turbine-like Moderators by Musun code:

/WLGD/detector/setGeometry baseline             # setting the geometry of the detector to the baseline design
/WLGD/event/saveAllEvents 0                     # only the Ge77 producing events are saved
/WLGD/detector/With_NeutronModerators 2         # using the moderator design with the tubes right around the re-entrance tubes
/WLGD/detector/With_Gd_Water 1                  # using the Gd in the water
/WLGD/detector/TurbineAndTube_Radius 200       # set the radius on which the center of mass of the pannels are alligned on [cm]
/WLGD/detector/TurbineAndTube_Length 100       # set the length of the moderator pannelss [cm]
/WLGD/step/getDepositionInfo 1                  # save the information of multiplicity and total energy deposited in detectors
/run/initialize                                 
/WLGD/generator/setGenerator Musun              # set the primary generator to the (Alpha,n) generator in the moderators
/WLGD/generator/setMUSUNFile path/to/file       # see the example/example_musun_file.dat
/run/beamOn 100                                 # should never exceed the size of the musun input file

Example for investigating the output of all muons and their individual energy depositions in the whole cryostat

/WLGD/detector/setGeometry baseline             # setting the geometry of the detector to the baseline design
/WLGD/event/saveAllEvents 1                     # only the Ge77 producing events are saved
/WLGD/step/getDepositionInfo 1                  # save the information of multiplicity and total energy deposited in detectors
/WLGD/step/getIndividualDepositionInfo 1        # save the information of individual energy depositions inside the cryostat
/run/initialize                                 
/WLGD/generator/setGenerator Musun              # set the primary generator to the (Alpha,n) generator in the moderators
/WLGD/generator/setMUSUNFile path/to/file       # see the example/example_musun_file.dat
/run/beamOn 100                                 # should never exceed the size of the musun input file