GeoMag and HelMod webmodels version for magnetosphere and heliosphere transport of cosmic rays

P. Bobik; M. J. Boschini; C. Consolandi; S. Della Torre; M. Gervasi; D. Grandi; K. Kudela; G. La Vacca; S. Pensotti; M. Putis; P. G. Rancoita; D. Rozza; M. Tacconi

arXiv · 1307.5196

GeoMag and HelMod webmodels version for magnetosphere and heliosphere transport of cosmic rays

P. Bobik·M. J. Boschini·C. Consolandi·S. Della Torre·M. Gervasi·D. Grandi·K. Kudela·G. La Vacca·S. Pensotti·M. Putis·P. G. Rancoita·D. Rozza·M. Tacconi

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Abstract

We implemented a website to deal with main effects on Cosmic Ray access to the Earth, i.e. the Solar Modulation and the Geomagnetic Field effect. In helmod.org the end user can easily access a web interface to results catalog of the HelMod Monte Carlo Code. This Model uses a Monte Carlo Approach to solves the Parker Transport Equation, obtaining a modulated proton flux for a period (monthly average) between January 1990 and december 2007. geomagsphere.org is instead based on GeoMag Backtracing Code, that solves the Lorentz equation with a Runge-Kutta method of 6th order, and, reversing charge sign and velocity, reconstruct particle trajectories in the Earth Magnetosphere back in time. We use last models of internal (IGRF-11) and external (Tsyganenko 1996 -T96- and 2005 -T05-) field components valid up to 2015. Particles are backtraced to the outer (magnetopause) or inner boundary to separate Primary (allowed trajectory) from Secondary (forbidden) Cosmic Rays. This code has been used both for reproducing known effects as East-West effect and rigidity cutoff calculations. In geomagsphere.org the user can choose the external field model from Tsyganenko (T96 or T05) and obtain for a fixed position and date from 1st Jan. 1968 (T96) and 1st Jan. 1995 (T05) respectively till 31$^{st}$ Dec 2012, the vertical rigidity cutoff estimation obtained with the backtracing technique with a rigidity step of 0.1 GV. For a more precise calculation (0.01 GV), requiring more CPU time, results are sent to the user by email (mail model)

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BibTeX RIS

P. Bobik, M. J. Boschini, C. Consolandi, S. Della Torre, M. Gervasi, D. Grandi, K. Kudela, G. La Vacca, S. Pensotti, M. Putis, P. G. Rancoita, D. Rozza, M. Tacconi. 2013-07-19. GeoMag and HelMod webmodels version for magnetosphere and heliosphere transport of cosmic rays. https://arxiv.org/abs/1307.5196

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