Searches on dark matter and for the ultra high energy cosmic ray composition: probes of extensions of the standard model of particle physics

• Grant number: 13/25433-7
• Support type: Regular Research Grants
• Duration: March 01, 2014 - February 29, 2016
• Field of knowledge: Physical Sciences and Mathematics - Physics - Elementary Particle Physics and Fields
• Principal researcher: Edivaldo Moura Santos
• Grantee: Edivaldo Moura Santos
• Home Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

In this project, we propose to investigate two current puzzles in astroparticle physics: the dark matter and the ultra high energy cosmic rays (UHECR) compositions. The common goal of these two fronts is to probe extensions of the standard model of particle physics. In relation to dark matter our investigations will take place in two fronts: analysis of intrinsic dark matter properties, and probes of extensions of the standard model of particle physics which propose dark matter candidates. Once we understand the fundamental aspects ofsuch intrinsic properties and extension models, our goals are: 1) to determine which experimental signatures they convey, and 2) search for these signatures in experimental data, or if this data is absent, determine the experimental sensitivity to probe these signatures. Wewill investigate these signatures both directly and indirectly. The latter searches for the dark matter annihilation or decay products. For this reason our project includes investigation of highenergy neutrinos, gamma and cosmic rays. It gives continuity to the investigation we have been carrying on for a few years. As an example of results already achieved, we have excluded a large region of the strongly interacting massive particles parameter space region.In relation to UHECR, we intend to continue our investigations on its composition. We aim to build methods that allows us to discriminate photon induced from nucleon or nucleus induced showers. Although the bulk of UHECR seems to be composed by either of the later, the upperlimit for photon induced showers with energies above $5 \times 10^{19}$ is $30\%$. The presence of photons in the UHECR spectrum can elucidate their production mechanism, as well as point to the existence of new phenomena. Given these aspects, our research can help to reveal yet unknown astrophysical phenomena as well as the presence of beyond the standard model particles. (AU)