scholarly journals Counter-based pseudorandom number generators for CORSIKA 8

2021 ◽  
Vol 251 ◽  
pp. 03039
Author(s):  
A. Augusto Alves ◽  
Anton Poctarev ◽  
Ralf Ulrich

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.

2019 ◽  
Vol 64 (7) ◽  
pp. 646
Author(s):  
I. Valiño

We highlight the main results obtained by the Pierre Auger Collaboration in its quest to unveil the mysteries associated with the nature and origin of the ultra-high energy cosmic rays, the highest-energy particles in the Universe. The observatory has steadily produced high-quality data for more than 15 years, which have already led to a number of major breakthroughs in the field contributing to the advance of our understanding of these extremely energetic particles. The interpretation of our measurements so far opens new questions which will be addressed by the on-going upgrade of the Pierre Auger Observatory.


2016 ◽  
Vol 2016 (05) ◽  
pp. 038-038 ◽  
Author(s):  
Rafael Alves Batista ◽  
Andrej Dundovic ◽  
Martin Erdmann ◽  
Karl-Heinz Kampert ◽  
Daniel Kuempel ◽  
...  

2006 ◽  
Vol 39 (6) ◽  
pp. 831-841 ◽  
Author(s):  
Jean Jakoncic ◽  
Marco Di Michiel ◽  
Zhong Zhong ◽  
Veijo Honkimaki ◽  
Yves Jouanneau ◽  
...  

Single-wavelength anomalous diffraction (SAD), multiwavelength anomalous diffraction (MAD) and single isomorphous replacement with anomalous scattering (SIRAS) phasing at ultra-high X-ray energy, 55 keV, are used successfully to determine a high-quality and high-resolution experimental electronic density map of hen egg-white lysozyme, a model protein. Several combinations, between single- and three-wavelength, with native data were exploited to demonstrate that standard phasing procedures with standard equipment and software can successfully be applied to three-dimensional crystal structure determination of a macromolecule, even at these very short wavelengths. For the first time, a high-quality three-dimensional molecular structure is reported from SAD phasing with ultra-high-energy X-rays. The quality of the crystallographic data and the experimental electron density maps meet current standards. The 2.7% anomalous signal from three Ho atoms, at the HoKedge, was sufficient to obtain a remarkable electron density and build the first lanthanide structure for HEWL in its entirety.


Author(s):  
Yoshichika Bando ◽  
Takahito Terashima ◽  
Kenji Iijima ◽  
Kazunuki Yamamoto ◽  
Kazuto Hirata ◽  
...  

The high quality thin films of high-Tc superconducting oxide are necessary for elucidating the superconducting mechanism and for device application. The recent trend in the preparation of high-Tc films has been toward “in-situ” growth of the superconducting phase at relatively low temperatures. The purpose of “in-situ” growth is to attain surface smoothness suitable for fabricating film devices but also to obtain high quality film. We present the investigation on the initial growth manner of YBCO by in-situ reflective high energy electron diffraction (RHEED) technique and on the structural and superconducting properties of the resulting ultrathin films below 100Å. The epitaxial films have been grown on (100) plane of MgO and SrTiO, heated below 650°C by activated reactive evaporation. The in-situ RHEED observation and the intensity measurement was carried out during deposition of YBCO on the substrate at 650°C. The deposition rate was 0.8Å/s. Fig. 1 shows the RHEED patterns at every stage of deposition of YBCO on MgO(100). All the patterns exhibit the sharp streaks, indicating that the film surface is atomically smooth and the growth manner is layer-by-layer.


Rare Metals ◽  
2021 ◽  
Author(s):  
Chao-Chao Zhou ◽  
Zhi Su ◽  
Xin-Lei Gao ◽  
Rui Cao ◽  
Shi-Chun Yang ◽  
...  

2020 ◽  
Vol 29 (1) ◽  
pp. 40-46
Author(s):  
Dmitri L. Khokhlov

AbstractThe studied conjecture is that ultra high energy cosmic rays (UHECRs) are hypothetical Planck neutrinos arising in the decay of the protons falling onto the gravastar. The proton is assumed to decay at the Planck scale into positron and four Planck neutrinos. The supermassive black holes inside active galactic nuclei, while interpreted as gravastars, are considered as UHECR sources. The scattering of the Planck neutrinos by the proton at the Planck scale is considered. The Planck neutrinos contribution to the CR events may explain the CR spectrum from 5 × 1018 eV to 1020 eV. The muon number in the Planck neutrinos-initiated shower is estimated to be larger by a factor of 3/2 in comparison with the standard model that is consistent with the observational data.


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