The ion composition of the galactic flux is derived from a code [Bad96] which considers all elemental groups from Z = 1 to Z = 28. The spectrum is modified to follow recent data sets (AMS [Alc00,Alc00a] and BESS [San00] data of 1998) up to 100 GeV according to the so-called ICRC2001 fit [Gai01]. The spectrum components are written into 28 files. The name of the files has the form (Z+phi+<PhiMV>+.spc). The first two characters of each file name are the atomic number of a different primary spectrum ion (e.g. 01:protons, 02:alpha...). They are followed by the solar modulation parameter used for generating the spectrum (7 characters) and by an extension ".spc". The ".spc" files are spectra without geomagnetic cutoff. The ".spc" files are used together with an analytical calculation of the rigidity cutoff, according to a centered dipole approximation of the Earth geomagnetic field, adapted to result in the vertical cutoff inserted into the input file (SPECSOUR command,SDUM=GCR-IONF,WHAT(2)of the continuation card), at the geomagnetic latitude and longitude of interest.
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