Dark matter evidence, particle physics candidates and detection methods

Abstract

The problem of the dark matter in the universe is reviewed. A short history of the subject is given, and several of the most obvious particle candidates for dark matter are identified. Particular focus is given to weakly interacting, massive particles (WIMPs) of which the lightest supersymmetric particle is an interesting special case and a useful template. The three detection methods: in particle accelerators, by direct detections of scattering in terrestrial detectors, and indirect detection of products from dark matter particle annihilation in the galactic halo, are discussed and their complementarity is explained. Direct detection experiments have revealed some possible indications of a dark matter signal, but the situation is quite confusing at the moment. Very recently, also indirect detection has entered a sensitivity region where some particle candidates could be detectable. Indeed, also here there are some (presently non‐conclusive) indications of possible dark matter signals, like an interesting structure at 130 GeV γ‐ray energy found in publicly available data from the Fermi‐LAT space detector. The future of the field will depend on whether WIMPs are indeed the dark matter, something that may realistically be probed in the next few years. If this exciting scenario turns out to be true, we can expect a host of other, complementary experiments in the coming decade. If it is not true, the time scale and methods for detection will be much more uncertain.

Cold ultrarelativistic pulsar winds as potential sources of galactic gamma-ray lines above 100 GeV

“…Despite the marginal statistical significance of the reported signals and some outstanding questions and inconsistencies, the implications of these results are hotly debated, basically in the context of dark matter (DM). This is motivated not only by the recognition of the potential of gamma-ray observations for indirect searches of DM (for a recent review see Bergström 2012) and the overall excitement caused by the possible association of the gamma-ray line at 130 GeV with DM (see e.g. Buckley & Hooper 2012), but also by the unusual characteristics of the signal.…”

Exploring MSSM for charge and color breaking and other constraints in the context of Higgs@125 GeV

“…Thereafter, within the above section we will show the results of scanning over a wide region of µ − A t plane for a moderate as well as for a large value of tan β. We also discuss the compatibility of our analysis with relevant low energy constraints like those from B-physics and cosmological constraints from neutralino dark matter [48][49][50][51]. We will further discuss the issue of muon g − 2 in the context of long-lived vacuum scenario, presenting also a few benchmark points.…”

Search for annihilating Dark Matter towards dwarf galaxies with the Cherenkov Telescope Array

“…However, the expected high background in very high energy gamma rays makes it hard to separate the DM signal from the gammarays of astrophysical origin. On the other hand, the dSphs are believed to be the smallest and faintest astronomical objects whose dynamics is dominated by DM, and they are free from gamma-ray astrophysical backgrounds [10]. Furthermore, ongoing optical surveys (such as DES, PanSTARSS, VLT, ATLAS), devoted to explore large areas of the sky, are increasing the pool of new dSphs in the Local Group and the knowledge needed to better constrain the values of the J-factors.…”