This package provides functionalities to define and handle reactions and decays. Elements involved in these processes can be customized given a user-defined class and data-base. A bulitin implementation of the PDG database of particles and nuclei is included.

The Reactions package allows to define a work with trees of processes among different elements. These processes can be either a reaction, where one or more reactants generate a set of products; or a decay, where a single element generates a set of products. This package is written in C++ as a header-only library, and has a python interface. The usage is very similar in both of them.

This package is distributed as a header-only library for C++ and pip-installable package in python. There is no need to install any external software.

However, in order to correctly set the paths to the databases it is needed to execute build the package. This can be easily done by calling

mkdir build
cd build
cmake ../
make install

The installed headers will be placed under build/include. Afterwards, the package can be easily used by simply including the previous path in your set of directories to search for headers. Consider the following code snippet:

#include "reactions/all.hpp"
int main() {
   auto r = reactions::make_reaction<reactions::string_element>("A B -> C D");
   std::cout << "Reaction number of reactants/products: " << r.reactants().size() << '/' << r.products().size() << std::endl;
   auto d = reactions::make_decay<reactions::pdg_element>("pi+ -> mu+ nu_mu");
   std::cout << "Decay head/number of products: " << r.head().as_element().name() << '/' << r.products().size() << std::endl;
   return 0;
}

To compile it, you just need to place the latter in a test.cpp script and compile it with

gcc -std=c++17 -I build/include -o test.cpp

This package uses the C++ standard greater or equal to 17, so remember to specify the -std=c++17 flag to your preferred compiler.