Galactic searches for dark matter

For nearly a century, more mass has been measured in galaxies than is contained in the luminous stars and gas. Through continual advances in observations and theory, it has become clear that the dark matter in galaxies is not comprised of known astronomical objects or baryonic matter, and that identification of it is certain to reveal a profound connection between astrophysics, cosmology, and fundamental physics. The best explanation for dark matter is that it is in the form of a yet undiscovered particle of nature, with experiments now gaining sensitivity to the most well-motivated particle dark matter candidates. In this article, I review measurements of dark matter in the Milky Way and its satellite galaxies and the status of Galactic searches for particle dark matter using a combination of terrestrial and space-based astroparticle detectors, and large scale astronomical surveys. I review the limits on the dark matter annihilation and scattering cross sections that can be extracted from both astroparticle experiments and astronomical observations, and explore the theoretical implications of these limits. I discuss methods to measure the properties of particle dark matter using future experiments, and conclude by highlighting the exciting potential for dark matter searches during the next decade, and beyond.     

Recent developments in dark matter searches

A brief review is first given of the forms of dark matter that are hypothesized, and a summary of the basic observational evidence for dark matter is provided. Then a summary of recent results from indirect and direct detection dark matter search experiments is given. Some discussion is also done of MOND theories along with recent analysis of galaxy surface density data that provides some support for such theories.     

Indirect searches for dark matter

The current status of indirect searches for dark matter has been reviewed in a schematic way here. The main relevant experimental results of the recent years have been listed and the excitements and disappointments that their phenomenological interpretations in terms of almost-standard annihilating dark matter have brought along have been discussed. The main sources of uncertainties that affect this kind of searches are also listed. [Report number: Saclay T11/206, CERN-PH-TH/2011-257, extended version in arXiv:1202.1454], [Prepared for the Proceedings of Lepton?CPhoton 2011, Mumbai, India, 22?C27 Aug. 2011].     

Direct detection searches for WIMP dark matter

A very active hunt is underway to discover the composition of dark matter in the universe. A large effort is devoted to the direct detection of dark matter through interactions with detectors in the laboratory. In this paper, we give an overview of the dark matter problem, discuss some of the design considerations taken in direct detection experiments, and describe some of the current efforts to discover Weakly Interacting Massive Particles (WIMPs), a well-motivated class of candidates for dark matter.     

Effective field theory of the Majorana dark matter

We revisit the thermal Majorana dark matter from the viewpoint of the minimal effective field theory. In this framework, analytical results for dark matter annihilation into Standard Model particles are derived. The dark matter parameter space, subject to the latest LUX, Panda X-Ⅱ and Xenon-1 T limits, is presented in a model-independent way. Applications to the singlet-doublet and MSSM are presented.     

Effective field theory approach to lepto-philic self-conjugate dark matter

We study self-conjugate dark matter(DM)particles interacting primarily with Standard Model(SM)leptons in an effective field theoretical framework.We consider SM gauge-invariant effective contact interactions between Majorana fermion,real scalar and real vector DM with leptons by evaluating the Wilson coefficients appropriate for interaction terms up to dimension 8,and obtain constraints on the parameters of the theory from the observed relic density,indirect detection observations and from the DM-electron scattering cross-sections in direct detection experiments.Low energy LEP data has been used to study sensitivity in the pair production of low mass(≤80 GeV)DM particles.Pair production of DM particles of mass≥50 GeV in association with mono-photons at the proposed ILC has rich potential to probe such effective operators.     

Indirect searches for dark matter with AMS-02

AMS-02 is a multi-purpose spectrometer with superconducting magnet, and is designed for 3 years of data taking aboard the International Space Station. Its high performance regarding particle identification and energy measurement will allow performing indirect searches for dark matter (DM) in different channels simultaneously: gamma rays, positrons and antiprotons. AMS-02 sensitivity to those signals are presented and – provided the positron excess is due to DM signal – it is shown that it allows to probe new physics models in detail. Its high sensitivity could even be a unique opportunity to reach the Majorana nature of the DM particle through final state polarization effects. PACS  95.35.+d; 95.55.Vj     

A review of indirect searches for particle dark matter

The indirect detection of dark matter annihilation and decay using observations of photons, charged cosmic rays and neutrinos offers a promising means of identifying the particle nature of this elusive component of the universe. The last decade has seen substantial advances in observational data-sets, complemented by new insights from numerical simulations, which together have enabled for the first time strong constraints on dark matter particle models, and have revealed several intriguing hints of possible signals. This review provides an introduction to indirect detection methods and an overview of recent results in the field.     

Nucleon propagation through nuclear matter in chiral effective field theory

We treat the propagation of a nucleon in nuclear matter by evaluating the ensemble average of the two-point function of the nucleon currents in the framework of chiral effective field theory. We first derive the effective parameters of the nucleon to one loop. The resulting formula for the effective mass has been known since before and gives an absurd value at normal nuclear density. We then modify it following Weinberg’s method for the two-nucleon system in the effective theory. Our results for the effective mass and the width of the nucleon are compared with those in the literature. PACS 11.30.Rd; 12.38.Lg; 12.39.Fe; 24.85.+p     

Testing ATLAS diboson excess with dark matter searches at LHC

Journal of High Energy Physics - Recently an orthogonal basis of $$ {mathcal{W}}_N $$ -algebra (AFLT basis) labeled by N-tuple Young diagrams was found in the context of 4D/2D duality. Recursion...     

Model-independent assessment of current direct searches for spin-dependent dark matter

I evaluate the current results of spin-dependent weakly interacting massive particle searches within a model-independent framework, showing the most restrictive limits to date derive from the combination of xenon and sodium iodide experiments. The extension of this analysis to the case of positive signal experiments is elaborated.     

Indirect dark matter searches in our Galaxy in comparison with FERMI data

The first 2-year data on the diffuse gamma rays from the FERMI satellite are analyzed and compared with expectations from dark matter annihilation. Although the published results at intermediate latitudes do not confirm the EGRET GeV excess, the data towards the Galactic center are hard to explain with standard propagation models. Redoing a template shape fit to the data in about 900 independent sky directions reveals that the FERMI data are best described by including a DMA contribution from an NFW DM profile with a ringlike DM substructure, as required to describe the new precise data on the gas flaring and rotation curve.