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The effect pointed out by A. B. Migdal in 1940's (hereafter named Migdal effect) has so far been usually neglected in the direct searches for WIMP Dark Matter candidates. This effect consists in the ionization and the excitation of bound atomic electrons induced by the recoiling atomic nucleus. In the present paper the related theoretical arguments are developed and some consequences of the proper accounting for this effect are discussed by some examples of practical interest.

It is known that the smallest size of the structures of the Universe with the weakly interacting massive dark matter is determined by the scale that enters the Hubble horizon at the time of kinetic decoupling of WIMP. This comes from the fact that the perturbation at smaller scales is erased due to the collisional damping during the kinetic decoupling. However the isocurvature mode is not affected and continue to be constant. We discuss about the generation of the isocurvature mode of WIMP dark matter at small scales recently found by Choi, Gong, and Shin¹ and its implications for the indirect detection of dark matter through the formation of the small size of halos.

It was recently proposed that weakly interacting massive particles (WIMP) may provide new ways of generating the observed baryon asymmetry in the early universe, as well as addressing the cosmic coincidence between dark matter (DM) and baryon abundances. This suggests a new possible connection between weak scale new particle physics and modern cosmology. This review summarizes the general ideas and simple model examples of the two recently proposed WIMP baryogenesis mechanisms: baryogenesis from WIMP DM annihilation during thermal freeze-out, and baryogenesis from metastable WIMP decay after thermal freeze-out. This review also discusses the interesting phenomenology of these models, in particular, the experimental signals that can be probed in the intensity frontier experiments and the large hadron collider (LHC) experiments.

It is now well established and accepted that roughly 25% of the total mass-energy density of the Universe is in the form of non-relativistic particles. That these particles, referred to as Dark Matter, have remained a mystery has served as motivation for the design and implementation of increasingly ingenious and far reaching experiments in an attempt to identify and understand them. This paper will review various ongoing Dark Matter searches with focus on the variety of techniques and implementation used to both detect the rare Dark Matter interactions as well as reject the vast number of background events.

Theoretical and experimental techniques employed in dedicated searches for dark matter at hadron colliders are reviewed. Bounds from the 7 TeV and 8 TeV proton–proton collisions at the Large Hadron Collider (LHC) on dark matter interactions have been collected and the results interpreted. We review the current status of the Effective Field Theory picture of dark matter interactions with the Standard Model. Currently, LHC experiments have stronger bounds on operators leading to spin-dependent scattering than direct detection experiments, while direct detection probes are more constraining for spin-independent scattering for WIMP masses above a few GeV.

Direct detection of WIMPs is key to understand the origin and composition of Dark Matter. Among the many experimental techniques available, those providing directional information have the potential of yielding an unambiguous observation of WIMPs even in the presence of insidious backgrounds. A measurement of the distribution of arrival direction of WIMPs can also discriminate between Galactic Dark Matter halo models. Here, we will discuss the motivation for directional detectors and review the experimental techniques used by the various experiments. We will then describe the DMTPC detector in more detail.

We study the spin-dependent WIMP scattering off nuclei for a variety of targets of experimental interest. In evaluating the spin structure functions, we have included the recently proposed leading long-range two-body currents in the most important isovector contribution. We show, however, that such effects are essentially independent of the target nucleus and, as a result, they can be treated as a mere renormalization of the effective nucleon cross-section or, equivalently, of the corresponding effective coupling, with reduction factors around 25%. Using these effects in the spin structure functions, we compute the relevant event rates due to the spin for various targets of experimental interest.

In this paper, we revisit our model-independent methods developed for reconstructing properties of Weakly Interacting Massive Particles (WIMPs) by using measured recoil energies from direct Dark Matter detection experiments directly and take into account more realistically non-negligible threshold energy. All expressions for reconstructing the mass and the (ratios between the) spin-independent and the spin-dependent WIMP–nucleon couplings have been modified. We focus on low-mass ($m_{\chi }\lesssim 15$ GeV) WIMPs and present the numerical results obtained by Monte Carlo simulations. Constraints caused by non-negligible threshold energy and technical treatments for improving reconstruction results will also be discussed.

We reexamine the model-independent data analysis methods for extracting properties of Weakly Interacting Massive Particles (WIMPs) by using data (measured recoil energies) from direct Dark Matter detection experiments directly and, as a more realistic study, consider a small fraction of residue background events, which pass all discrimination criteria and then mix with other real WIMP-induced signals in the analyzed data sets. In this talk, the effects of residue backgrounds on the determination of the WIMP mass as well as the spin-independent WIMP coupling on nucleons will be discussed.

In this paper, we investigate the modification of our expressions developed for the model-independent data analysis procedure of the reconstruction of the (time-averaged) one-dimensional velocity distribution of galactic weakly interacting massive particles (WIMPs) with a nonnegligible experimental threshold energy. Our numerical simulations show that, for a minimal reconstructable velocity of as high as km/s, our model-independent modification of the estimator for the normalization constant could provide precise reconstructed velocity distribution points to match the true WIMP velocity distribution with ≲ 10% bias.

In this article I review model-independent procedures for extracting properties of Weakly Interacting Massive Particles (WIMPs) from direct Dark Matter detection experiments. Neither prior knowledge about the velocity distribution function of halo Dark Matter particles nor about their mass or cross sections on target nucleus is needed. The unique required information is measured recoil energies from experiments with different detector materials.

We consider the hypothesis that dark matter is made of weakly interacting massive particles (WIMPs) and describe how their pair annihilation in the galactic halo generates exotic cosmic ray fluxes. Features for generic WIMP models are reviewed, pointing out cases in which clear signatures arise. Implications from available and upcoming measurements are discussed.

We shall consider the problem of Dark Matter (DM) in torsion gravity with Dirac matter fields; we will consider the fact that if Weakly-Interacting Massive Particles in a bath are allowed to form condensates then torsional effects may be relevant even at galactic scales: we show that torsionally-gravitating Dirac fields have interesting properties for the problem of DM. We discuss consequences.