Studies of the cosmic ray spectrum and large scale anisotropies with the KASCADE-Grande experiment

KASCADE-Grande is an air shower observatory devoted to the detection of cosmic rays in the 10$^{16}$ − 10$^{18}$eV energy range. For each event the arrival direction, the total number of charged particles (Nch) and the total number of muons (Nμ), at detection level (i.e. 110 m a.s.l.), are measured. The detection of these observarbles, with high accuracy, allows the study of the primary spectrum, chemical composition and large scale anisotropies, that are the relevant informations to investigate the astrophysics of cosmic rays in this energy range. These studies are of main importance to deeply investigate the change of slope of the primary spectrum detected at ∼ 4×10$^{15}$eV , also known as the knee, and to search for the transition from galactic to extra-galactic cosmic rays. The two-dimensional (Nch vs Nμ) spectrum is the basis for the cosmic-ray chemical composition studies. EAS and detection fluctuations prevent the measurement of the primary mass on an event by event basis, nevertheless the precision obtained by the KASCADE-Grande experiment allows to separate events into mass groups. A search for anisotropies in the arrival directions of primary cosmic rays has been performed using the East-West analysis technique with the events detected by the Grande array. ... mehrFirst harmonic modulation has been derived from the distributions (in sidereal, solar and anti-sidereal times) of the counts difference from the East and West sectors. In this contribution we present and discuss the latest experimental results.