An analysis of anisotropies in the arrival directions of galactic electrons and positrons, as well as protons, Helium, Carbon and Oxygen has been performed with the Alpha Magnetic Spectrometer on the International Space Station using the first 6.5 years (electrons and positrons) and the first 7.5 years (protons, Helium, Carbon, Oxygen) of data taking. Results on a dipole signal in Galactic coordinates are reported. The arrival directions of all studied cosmic ray species are consistent with isotropy. For energies above 16 GeV a limit of δ < 0.019 (δ < 0.005) at the 95% confidence level is obtained for positrons (electrons). For rigidities above 200 GV a limit of δ < 0.0038 (δ < 0.0036, δ < 0.019, δ < 0.017) at the 95% confidence level is obtained for protons (Helium, Carbon, Oxygen). The quoted limits are based on a total of 9.9×104 (1.3×106, 2×106,2.2×106, 6.1×104, 6.3×104) positron (electron, proton, Helium, Carbon, Oxygen) events.
Anisotropy of particle fluxes in primary cosmic rays measured with the alpha magnetic spectrometer on the ISS
Graziani M.;
2019
Abstract
An analysis of anisotropies in the arrival directions of galactic electrons and positrons, as well as protons, Helium, Carbon and Oxygen has been performed with the Alpha Magnetic Spectrometer on the International Space Station using the first 6.5 years (electrons and positrons) and the first 7.5 years (protons, Helium, Carbon, Oxygen) of data taking. Results on a dipole signal in Galactic coordinates are reported. The arrival directions of all studied cosmic ray species are consistent with isotropy. For energies above 16 GeV a limit of δ < 0.019 (δ < 0.005) at the 95% confidence level is obtained for positrons (electrons). For rigidities above 200 GV a limit of δ < 0.0038 (δ < 0.0036, δ < 0.019, δ < 0.017) at the 95% confidence level is obtained for protons (Helium, Carbon, Oxygen). The quoted limits are based on a total of 9.9×104 (1.3×106, 2×106,2.2×106, 6.1×104, 6.3×104) positron (electron, proton, Helium, Carbon, Oxygen) events.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.