Computer Physics Communications Program Library

Programs in Physics & Physical Chemistry

PROGRAM SUMMARY

Manuscript Title: Simulation of Ultra-High Energy Photon Propagation in the Geomagnetic Field
Authors: P. Homola, D. Góra, D. Heck, H. Klages, J. Pekala, M. Risse, B. Wilczynska nd H. Wilczynski
Program title: PRESHOWER 1.0
Catalogue identifier: ADWG
Journal reference: Comput. Phys. Commun. 173(2005)71
Programming language: C, FORTRAN 77.
Computer: Intel-Pentium based PC.
Operating system: Linux, DEC-Unix.
RAM: < 100kB
Word size: 32
Keywords: ultra-high energy cosmic rays, extensive air showers, geomagnetic cascading, gamma conversion.
PACS: 13.85.Tp, 95.85.Ry, 96.40.Pq, 98.70.Sa.
Classification: 1.1.
Nature of problem: Simulation of a cascade of particles initiated by UHE photon passing through the geomagnetic field above the Earth's atmosphere.
Solution method: The primary photon is tracked until its conversion into a e⁺e^- pair or until it reaches the upper atmosphere. If conversion occurred each individual particle in the resultant preshower is checked for either bremsstrahlung radiation (electrons) or secondary gamma conversion (photons). The procedure ends at the top of the atmosphere and the shower particle data are saved.
Restrictions: Gamma conversion into particles other than electron pairs hasn't been taken into account.
Running time: 100 preshower events with primary energy 10²⁰ eV require a 800 MHz CPU time of about 50 min., with 10²¹ eV the simulation time for 100 events grows up to 500 min.