NuOscillator

NuOscillator is a wrapper around oscillation calculators, enabling the computation of oscillation probabilities for various configurations, including beam oscillations, atmospheric oscillations, and sterile neutrinos with NSI effects.

The framework has been adapted to integrate seamlessly with oscillation fitters like MaCh3.

How to start

mkdir build;
cd build;
cmake ../ -DUseGPU=0 -DUseMultithreading=1 -DUseDoubles=0 -DUseCUDAProb3=0 -DUseCUDAProb3Linear=1 -DUseProb3ppLinear=1 -DUseNuFASTLinear=1 -DUseProbGPULinear=0
make -jN [Where N is number of threads]
make install

don't forget about

source Linux/bin/setup.NuOscillator.sh

then you can check if everything runs correctly by

cd ../
./build/Linux/bin/DragRace

How to Integrate in Framework

Recommended way is to use CPM within you CmakeList.txt

CPMAddPackage(
  NAME NuOscillator
    VERSION 0.0
    GITHUB_REPOSITORY "dbarrow257/NuOscillator"
    GIT_TAG "main"
    OPTIONS
    "UseGPU 0"
    "UseMultithreading 1"
    "UseDoubles 1"

    "UseCUDAProb3Linear 0"
    "UseCUDAProb3 0"
    "UseProbGPULinear 0"
    "UseProb3ppLinear 0"
    "UseNuFASTLinear  1"
    "UseOscProb  1"
)

Implemented Engines

UseCUDAProb3 etc. refers to implemented engines. Engines are loaded via yaml config files. In principle you can compile all of them and select one you want to use via config.

Following neutrino oscillation calculators are available:

Oscillator	Hardware	Source	Reference
CUDAProb3Linear	CPU/GPU	Beam
CUDAProb3	CPU/GPU	Atm	Ref
ProbGPULinear	GPU	Beam	Ref
Prob3++Linear	CPU	Beam
NuFastLinear	CPU	Beam	Ref
OscProb	CPU	Atm

GPU

Some engines requires gpu like ProbGPULinear other can use both CPU and GPU. To use GPU functionality remember about

cmake ../ -DUseGPU=1

You can also pass CUDA architectures via cmake to ensure consistent architectures in multiple packages:

cmake ../ -DCMAKE_CUDA_ARCHITECTURES="all"

Compiler Flags

NuOscillator natively doesn't include many c++ compiler flags (this include optimalisation flags). Since package is intended to be used withing other (fitting) frameworks we allow to pass compiler flags via cmake.

cmake ../ -DNuOscillator_Compiler_Flags="-O3;-g;-Wextra;-Wall"

This give full freedom to users in how to configure NuOscillator.

How to Use in Fitting Framework

First initialise factory to produce engine defined by config. See exmaples of configs here

auto OscillFactory = std::make_unique<OscillatorFactory>();

std::string NuOscillatorConfigFile = "configs/NuFASTLinear.yaml");
NuOscProbCalcers = OscillFactory->CreateOscillator(NuOscillatorConfigFile);

Now you need specify energy bins for which oscillation are going to be calculated. Energy must be in GeV! It is good practice to sort energy values as NuOscillator expect them in ascending order.

std::vector<double> EnergyArray = {0, 0.6, 1, 10};
std::sort(EnergyArray.begin(),EnergyArray.end());

Lastly pass energy vector and finish setup

if (!NuOscProbCalcers->EvalPointsSetInConstructor()) {
  NuOscProbCalcers->SetEnergyArrayInCalcer(EnergyArray);
}
NuOscProbCalcers->Setup();

Intended extensions

• Inclusion of NuSQUIDS oscillation engine
• Better handling of oscillation parameter pass through
• Inclusion of linear propagation in OscProb