Search

Low energy cosmic rays are modulated by the solar activity when they propagation in the heliosphere, leading to ambiguities in understanding their acceleration at sources and propagation in the Milky Way. By means of the precise measurements of the e − , e + , e − + e + , and e + / (e − + e +) spectra by AMS-02 near the Earth, as well as the very low energy measurements of the e − + e + fluxes by Voyager-1 far away from the Sun, we derive the local interstellar spectra (LIS) of e − and e + components individually. Our method is based on a non-parametric description of the LIS of e − and e + and a force-field solar modulation model. We then obtain the evolution of the solar modulation parameters based on the derived LIS and the monthly fluxes of cosmic ray e − and e + measured by AMS-02. To better fit the monthly data, additional renormalization factors for e − and e + have been multiplied to the modulated fluxes. We find that the inferred solar modulation parameters of positrons are in good agreement with that of cosmic ray nuclei, and the time evolutions of the solar modulation parameters of electrons and positrons differ after the reversal of the heliosphere magnetic field polarity, which shows clearly the charge-sign dependent modulation effect. [ABSTRACT FROM AUTHOR]

Abstract One of the main purposes of the DArk Matter Particle Explorer (DAMPE) is to measure the cosmic ray nuclei up to several tens of TeV or beyond, whose origin and propagation remains a hot topic in astrophysics. The Plastic Scintillator Detector (PSD) on top of DAMPE is designed to measure the charges of cosmic ray nuclei from H to Fe and serves as a veto detector for discriminating gamma-rays from charged particles. We propose in this paper a charge reconstruction procedure to optimize the PSD performance in charge measurement. Essentials of our approach, including track finding, alignment of PSD, light attenuation correction, quenching and equalization correction are described detailedly in this paper after a brief description of the structure and operational principle of the PSD. Our results show that the PSD works very well and almost all the elements in cosmic rays from H to Fe are clearly identified in the charge spectrum. [ABSTRACT FROM AUTHOR]

HERD is the High Energy cosmic-Radiation Detection instrument proposed to operate onboard China’s space station in the 2020s. It is designed to detect energetic cosmic ray nuclei, leptons and photons with a high energy resolution ( ∼1% for electrons and photons and 20% for nuclei) and a large geometry factor (>3 m 2  sr for electrons and diffuse photons and > [2]m 2  sr for nuclei). In this work we discuss the capability of HERD to detect monochromatic γ -ray lines, based on simulations of the detector performance. It is shown that HERD will be one of the most sensitive instruments for monochromatic γ -ray searches at energies between ∼ 10 to a few hundred GeV. Above hundreds of GeV, Cherenkov telescopes will be more sensitive due to their large effective area. As a specific example, we show that a good portion of the parameter space of a supersymmetric dark matter model can be probed with HERD. [ABSTRACT FROM AUTHOR]