vCHEP2021 - 25th International Conference on Computing in High-Energy and Nuclear Physics
The CHEP conference series addresses the computing, networking and software issues for the world’s leading data‐intensive science experiments that currently analyse hundreds of petabytes of data using worldwide computing resources.
vCHEP 2021 will be held as a virtual event between Monday-Friday 17th-21st May 2021.
Counter-based pseudorandom number generators for CORSIKA 8
Authors: A. Augusto Alves Jr, Anton Poctarev, and Ralf Ulrich1
This document is devoted to the description of advances in the generation of high-quality random numbers for CORSIKA 8, which is being developed in modern C++17 and is designed to run on modern multi-thread processors and accelerators. CORSIKA 8 is a Monte Carlo simulation framework to model ultra-high energy secondary particle cascades in astroparticle physics. The aspects associated with the generation of high-quality random numbers on massively parallel platforms, like multi-core CPUs and GPUs, are reviewed and the deployment of counter-based engines using an innovative and multi-thread friendly API are described. The API is based on iterators providing a very well known access mechanism in C++, and also supports lazy evaluation. Moreover, an upgraded version of the Squares algorithm with highly efficient internal 128 as well as 256 bit counters is presented in this context. Performance measurements are provided, as well as comparisons with conventional designs are given. Finally, the integration into CORSIKA 8 is commented.
CORSIKA 8: A novel high-performance computing tool for particle cascade MonteCarlo simulations
Authors: Ralf Ulrich, Antonio Augusto Alves Junior, Maximilian Reininghaus, Remy Prechelt, Andre Schmidt
The CORSIKA 8 project is an international collaboration of scientists working together to deliver the most modern, flexible, robust and efficient framework for the simulation of ultra-high energy secondary particle cascades in matter. The main application is for cosmic ray air shower simulations, but is not limited to that. Besides a comprehensive collection of physics models and algorithms relevant for the field, also all possible interfaces to hardware acceleration (e.g.\ GPU) and parallelization (vectorization, multi-threading, multi-core) will be provided. We present the status and roadmap of this project. This code will soon be available for novel explorative studies and phenomonological research, and at the same time for massive productions runs for experiments.
A C++ CORSIKA 8 Cherenkov photons simulation
Authors: Matthieu Carrère, Luisa Arrabito, Johan Bregeon, David Parello, Philippe Langlois and Georges Vasileiadis
CORSIKA is a reference software for simulations of air showers induced by cosmic rays. It has been developed in Fortran 77 continuously over the last thirty years and includes more than 10 5 lines of code. So it becomes very difficult to add new physics features to CORSIKA 7. CORSIKA 8 aims to be the future of the CORSIKA project. It is a framework in C++17 which uses modern concepts in object oriented programming for an efficient modularity and flexibility. The CORSIKA 8 project aims to obtain high performance by exploiting techniques such as vectorization, gpu/cpu parallelization, extended use of static polymorphism and the most precise values of physical constants available. In this paper we focus on the Cherenkov photon propagation module of CORSIKA, which is of particular interest for gamma-ray experiments, like the Cherenkov Telescope Array. First, we present the optimizations that we have applied to the Cherenkov module thanks to the results of detailed profiling using performance counters. Then, we report our preliminary work to develop the Cherenkov Module in the CORSIKA 8 framework. Finally, we will demonstrate the first performance comparison with the current CORSIKA software as well as the validation of physics results.