We consider the formation and evolution of Axion Quark Nugget dark matter particles in the early universe. The goal of this work is to estimate the mass distribution of these objects and assess their ability to form and survive to the present day. We argue that this model allows a broad range of parameter space in which the AQN may account for the observed dark matter mass density, naturally explains a similarity between the "dark" and "visible" components, i.e. Ω dark ∼ Ω visible , and also offer an explanation for a number of other long standing puzzles such as "Primordial Lithium Puzzle" and "the Solar Corona Mystery" among many other cosmological puzzles.

We consider a dark matter (DM) model offering a very natural explanation of the observed relation, Ω dark ∼ Ω visible . This generic consequence of the model is a result of the common origin of both types of matter (DM and visible) which are formed during the same QCD transition. The masses of both types of matter in this framework are proportional to one and the same dimensional parameter of the system, ΛQCD. The focus of the present work is the detail study of the dynamics of the CP-odd coherent axion field a(x) just before the QCD transition. We argue that the baryon charge separation effect on the largest possible scales inevitably occurs as a result of merely existence of the coherent axion field in early Universe. It leads to preferential formation of one species of nuggets on the scales of the visible Universe where the axion field a(x) is coherent. A natural outcome of this preferential evolution is that only one type of the visible baryons remains in the system after the nuggets complete their formation. This represents a specific mechanism on how the baryon charge separation mechanism (when the Universe is neutral, but visible part of matter consists the baryons only) replaces the conventional "baryogenesis" scenarios.

We study a dark matter (DM) model offering a very natural explanation of two (naively unrelated) problems in cosmology: the observed relation ΩDM ∼ Ω visible and the observed asymmetry between matter and antimatter in the Universe, known as the "baryogenesis" problem. In this framework, both types of matter (dark and visible) have the same QCD origin, form at the same QCD epoch, and both proportional to one and the same dimensional parameter of the system, ΛQCD, which explains how these two, naively distinct, problems could be intimately related, and could be solved simultaneously within the same framework. More specifically, the DM in this model is composed by two different ingredients: the (well-studied) DM axions and (less-studied) the quark nuggets made of matter or antimatter. The focus of the present work is the quantitative analysis of the relation between these two distinct components contributing to the dark sector of the theory determined by ΩDM ≡ [ΩDM(nuggets) + ΩDM(axion)]. We argue that the nugget's DM component always traces the visible matter density, i.e. ΩDM(nuggets) ∼ Ω visible and this feature is not sensitive to the parameters of the system such as the axion mass ma or the misalignment angle θ0. It should be contrasted with conventional axion production mechanism due to the misalignment when ΩDM(axion) is highly sensitive to the axion mass ma and the initial misalignment angle θ0. We also discuss the constraints on this model related to the inflationary scale HI , non-observation of the isocurvature perturbations and the tensor modes. We also comment on some constraints related to varies axion search experiments.

The XMM-Newton observatory shows evidence with an 11σ confidence level for seasonal variation of the X-ray background in the near-Earth environment in the 2-6 keV energy range (Fraser et al. 2014). The interpretation of the seasonal variation given in Fraser et al. ( 2014) was based on the assumption that solar axions convert to X-rays in the Earth's magnetic field. There are many problems with this interpretation, since the axion-photon conversion must preserve the directionality of the incoming solar axion. At the same time, this direction is avoided by the observations because the XMM-Newton's operations exclude pointing at the Sun and at the Earth. The observed seasonal variation suggests that the signal could have a dark matter origin, since it is very difficult to explain with conventional astrophysical sources. We propose an alternative explanation which involves the so-called Axion Quark Nugget (AQN) dark matter model. In our proposal, dark matter is made of AQNs, which can cross the Earth and emit high energy photons at their exit. We show that the emitted intensity and spectrum is consistent with Fraser et al. (2014), and that our calculation is not sensitive to the specific details of the model. We also find that our proposal predicts a large seasonal variation, on the level of 20-25%, much larger than conventional dark matter models (1-10%). Since the AQN emission spectrum extends up to ∼100 keV, well beyond the keV sensitivity of XMM-Newton, we predict the AQN contribution to the hard X-ray and γ-ray backgrounds in the Earth's environment. The Gamma-Ray Burst Monitor (GBM) instrument, aboard the FERMI telescope, is sensitive to the 8 keV-40 MeV energy band. We suggest that the multi-year archival data from the GBM could be used to search for a seasonal variation in the near-Earth environment up to 100 keV as a future test of the AQN framework.

The Murchison Widefield Array (MWA) has recorded [1] impulsive radio events in the quiet solar corona at frequencies 98, 120, 132, and 160 MHz. We propose that these radio events represent the direct manifestation of the dark matter annihilation events within the so-called axion quark nugget (AQN) framework. It has been previously argued that the AQN annihilation events in the quiet solar corona [2, 3] can be identified with nanoflares originally conjectured by Parker long ago [4].In the present work we further support this claim by demonstrating that the radio observations [1], including the frequency of appearance, temporal and spatial distributions, energetics, and other related observables are nicely matching the generic consequences of the AQN annihilation events in the quiet corona. We propose to test these ideas by analyzing the correlated clustering radio impulsive events in the different frequency bands. We also make generic predictions for low (80 and 89) MHz and high (179, 196, 217 and 240) MHz frequency bands which had been already recorded but not published by [1] yet. We also suggest to test this proposal by studying possible cross-correlation between MWA radio signals and Solar Orbiter recording of the extreme ultraviolet photons (coined as the "campfires") to support or refute this proposal.