The present work studies the dynamics of axion quark nuggets introduced in \cite{zhitnitsky} and exploited in the works \cite{zhitnitsky2}-\cite{zhitnitsky13}. The new feature considered here is the possibility that these nuggets become ferromagnetic. This possibility was pointed out in \cite{tatsumi}, although ferromagnetism may also take place due some anomaly terms found in \cite{son}-\cite{son2}. The purpose of the present letter however, is not to give evidence in favor or against these statements. Instead, it is focused in some direct consequences of this ferromagnetic behavior, if it exists. The first is that the nugget magnetic field induces an electric field due to the axion wall, which may induce pair production by Schwinger effect. Depending on the value of the magnetic field, the pair production can be quite large. A critical value for such magnetic field at the surface of the nugget is obtained, and it is argued that the value of the magnetic field of \cite{tatsumi} is at the verge of stability and may induce large pair production. The consequences of this enhanced pair production may be unclear. It may indicate that the the nugget evaporates, but on the other hand it may be just an indication that the intrinsic magnetic field disappears and the nuggets evolves to a non magnetized state such as \cite{zhitnitsky}-\cite{zhitnitsky13}. The interaction of such magnetic and electric nugget with the troposphere of the earth is also analyzed. However, if the magnetic field does not decay before the actual universe, then this would lead to high energy electron flux due to its interaction with the electron gases of the Milky Way. This suggests that these magnetized quarks may be a considerably part of dark matter, but only if their hypothetical magnetic and electric fields are evaporated.
We explore the possibility that the Fast Radio Bursts (FRBs) are powered by magnetic reconnection in magnetars, triggered by Axion Quark Nugget (AQN) dark matter. In this model, the magnetic reconnection is ignited by the shock wave which develops when the nuggets' Mach number $M \gg 1$. These shock waves generate very strong and very short impulses expressed in terms of pressure $Δp/p\sim M^2$ and temperature $ΔT/T\sim M^2$ in the vicinity of (would be) magnetic reconnection area. We find that the proposed mechanism produces a coherent emission which is consistent with current data, in partic…
A network of synchronized detectors can increase the likelihood of discovering the QCD axion, within the Axion Quark Nugget (AQN) dark matter model. A similar network can also discriminate the X-rays emitted by the AQNs from the background signal. These networks can provide information on the directionality of the dark matter flux (if any), as well as its velocity distribution, and can therefore test the Standard Halo Model. We show that the optimal configuration to detect AQN-induced axions is a triangular network of stations 100 km apart. For X-rays, the optimal network is an array of tetrah…
We argue that dark matter in the form of macroscopically large nuggets of standard model quarks and antiquarks can help to alleviate the tension between standard model cosmology and the recent EDGES observation of a stronger than anticipated 21 cm absorption feature. The effect occurs as a result of the thermal emission from quark nugget dark matter at early times and at energies well below the peak of the CMB. Similar radiation at early times may also contribute a fraction of the GHz range excess observed by ARCADE2.
Telescope Array (TA) experiment has recorded \cite{Abbasi:2017rvx,Okuda_2019} several short time bursts of air shower like events. These bursts are very distinct from conventional single showers, and are found to be strongly correlated with lightnings. In our previous work \cite{Zhitnitsky:2020shd} we proposed that these bursts represent the direct manifestation of the dark matter (DM) annihilation events within the so-called axion quark nugget (AQN) model. In the present work we suggest to test this proposal to search for the radio signals in frequency band $ν\in (0.5-200)$ MHz which must be …
The Antarctic Impulse Transient Antenna (\textsc{ANITA}) collaboration [1-3] has reported two anomalous events with noninverted polarity. These events are hard to explain in terms of conventional cosmic rays (CRs). We explore a new possible explanation for these anomalous events by suggesting that these events can be related to the dark matter (DM) annihilations within the so-called axion quark nugget (AQN) DM model. This model was initially invented for a completely different purpose to explain the observed similarity between the dark and the visible components in the Universe, i.e. $Ω_{\rm D…
We study a dark matter (DM) model offering a very natural explanation of two (naively unrelated) problems in cosmology: the observed relation $Ω_{\rm DM}\simΩ_{\rm visible}$ 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, $Λ_{\rm QCD}$, which explains how these two, naively distinct, problems could be intimately related, and could be solved si…
The Horizon-10T collaboration \cite{Beisembaev:2016cyg,2017EPJWC.14514001B,Beznosko:2019cI,2019EPJWC.20806002B,Beisembaev:2019nzd} have reported observation of Multi-Modal Events (MME) containing multiple peaks suggesting their clustering origin. These events are proven to be hard to explain in terms of conventional cosmic rays (CR). We propose that these MMEs might be result of the dark matter annihilation events within the so-called axion quark nugget (AQN) dark matter model, which was originally invented for completely different purpose to explain the observed similarity between the dark an…
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. $Ω_{\rm dark}\sim Ω_{\rm visible}$, and also offer an explanation for a number of other long standing puzzles such as "Primordial Lit…
We study the new mechanism of the axion production suggested recently in [1,2]. This mechanism is based on the so-called Axion Quark Nugget (AQN) dark matter model, which was originally invented to explain the similarity of the dark and visible cosmological matter densities. We perform numerical simulations to evaluate the axion flux on the Earth's surface. We examine annual and daily modulations, which have been studied previously and are known to occur for any type of dark matter. We also discuss a novel type of short time enhancements which are unique to the AQN model: the statistical fluct…
We advocate an idea that the presence of the daily and annual modulations of the axion flux on the Earth surface may dramatically change the strategy of the axion searches. Our computations are based on the so-called Axion Quark Nugget (AQN) dark matter model which was originally put forward to explain the similarity of the dark and visible cosmological matter densities $Ω_{\rm dark}\sim Ω_{\rm visible}$. In our framework, the population of galactic axions with mass $ 10^{-6} {\rm eV}\lesssim m_a\lesssim 10^{-3}{\rm eV}$ and velocity $< v_a>\sim 10^{-3} c$ will be always accompanied by the axi…
We advocate an idea that the Axion Quark Nuggets (AQN) hitting the Earth can be detected by analysing the infrasound, acoustic and seismic waves which always accompany the AQN's passage in the atmosphere and underground. Our estimates for the infrasonic frequency $ν\simeq 5$ ~Hz and overpressure $δp\sim 0.3 ~$Pa for relatively large size dark matter (DM) nuggets suggest that sensitivity of presently available instruments is already sufficient to detect very intense (but very rare) events today with existing technology. A study of much more frequent but less intense events requires a new type o…
We review a testable, the axion quark nugget (AQN) model outside of the standard WIMP paradigm. The model was originally invented to explain the observed similarity between the dark and the visible components, $Ω_{\rm DM}\approx Ω_{\rm visible}$ in a natural way as both types of matter are formed during the same QCD transition and proportional to the same dimensional fundamental parameter of the system, $Λ_{\rm QCD}$. In this framework the baryogenesis is actually a charge segregation (rather than charge generation) process which is operational due to the $\cal{CP}$-odd axion field,while the g…
It has been recently argued [1-3] that there is a strong component of the diffuse far-ultraviolet (FUV) background which is hard to explain by conventional physics in terms of the dust-scattered starlight. We propose that this excess in FUV radiation might be result of the dark matter annihilation events within the so-called axion quark nugget (AQN) dark matter model, which was originally invented for completely different purpose to explain the observed similarity between the dark and the visible components in the Universe, i.e. $Ω_{\rm DM}\sim Ω_{\rm visible}$. We support this proposal by dem…
In this work we advocate for the idea that two seemingly unrelated 80-year-old mysteries - the nature of dark matter and the high temperature of the million degree solar corona - may have resolutions that lie within the same physical framework. The current paradigm is that the corona is heated by nanoflares, which were originally proposed as miniature versions of the observed solar flares. It was recently suggested that the nanoflares could be identified as annihilation events of the nuggets from the Axion Quark Nugget (AQN) dark matter model. This model was invented as an explanation of the o…
We study a testable dark matter (DM) model outside of the standard WIMP paradigm in which the observed ratio $Ω_{\rm dark} \simeq Ω_{\rm visible}$ for visible and dark matter densities finds its natural explanation as a result of their common QCD origin when both types of matter (DM and visible) are formed at the QCD phase transition and both are proportional to $Λ_{\rm QCD}$. Instead of conventional "baryogenesis" mechanism we advocate a paradigm when the "baryogenesis" is actually a charge separation process which always occur in the presence of the $\cal{CP}$ odd axion field $a(x)$. In this…
Telescope Array (TA) experiment has recorded \cite{Abbasi:2017rvx,Okuda_2019} several short time bursts of air shower like events. These bursts are very distinct from conventional single showers, and are found to be strongly correlated with lightnings. We propose that these bursts represent the direct manifestation of the dark matter annihilation events within the so-called axion quark nugget (AQN) model, which was originally invented for completely different purpose to explain the observed similarity between the dark and the visible components in the Universe, i.e. $Ω_{\rm DM}\sim Ω_{\rm visi…
Astrophysics today faces a number of mysteries which defiant their resolutions in spite of drastic improvements in instrumental design, better technique being developed, and gradual improvements in theoretical and computation methods over last decades. Primordial Lithium Puzzle is known to stay with us for at least two decades, and it is very likely that its final resolution will require some fundamentally new ideas, novel frameworks and a non-conventional paradigms. We propose that Primordial Lithium Puzzle finds its natural resolution within the so-called Axion Quark Nugget (AQN) dark matter…
We advocate the idea that the nanoflares conjectured by Parker long ago to resolve the corona heating problem, may also trigger the larger solar flares. The arguments are based on the model where emission of extreme ultra violet (EUV) radiation and soft x-rays from the Sun are powered externally by incident dark matter particles within the Axion Quark Nugget (AQN) Dark Matter Model. The corresponding annihilation events of the AQNs with the solar material are identified with nanoflares. This model was originally invented as a natural explanation of the observed ratio $Ω_{\rm dark} \sim Ω_{\rm …
The axion quark nuggets introduced in \cite{zhitnitsky}-\cite{zhitnitsky13} are a candidate for cold dark matter which, in addition, may be relevant in baryogenesis scenarios. The present work studies their evolution till they enter in the colour superconducting phase. This evolution was already considered in \cite{zhitnitsky5}, where it is concluded that a large chemical potential $μ$ is induced on the bulk of the object. The baryon number accumulated at the domain wall surrounding the object is taken as predominant in \cite{zhitnitsky5}, and it is suggested that internal and external fluxes …
The Murchison Widefield Array (MWA) recorded \cite{Mondal-2020} impulsive radio events in the quiet solar corona at frequencies 98, 120, 132, and 160 MHz. We propose that these radio events are the direct manifestation of dark matter annihilation events within the axion quark nugget (AQN) framework. It has been argued \cite{Zhitnitsky:2017rop,Raza:2018gpb} that the AQN annihilation events in the quiet solar corona can be identified with the nanoflares conjectured by Parker \cite{Parker-1983}. We further support this claim by demonstrating that observed impulsive radio events \cite{Mondal-2020}…
We review a testable dark matter (DM) model outside of the standard WIMP paradigm. The model is unique in a sense that the observed ratio $Ω_{\rm dark} \simeq Ω_{\rm visible}$ for visible and dark matter densities finds its natural explanation as a result of their common QCD origin when both types of matter (DM and visible) are formed during the QCD transition and both are proportional to single dimensional parameter of the system, $Λ_{\rm QCD}$. We argue that the charge separation effect also inevitably occurs during the same QCD transition in the presence of the $\cal{CP}$ odd axion field $a…
The DAMA/LIBRA experiment shows $9.5 σ$ evidence for an annual modulation in the $(1-6)~ {\rm keV}$ energy range, strongly suggesting that the observed modulation has the dark matter origin. However, the conventional interpretation in terms of WIMP-nucleon interaction is excluded by other experiments. We propose an alternative source of modulation in the form of neutrons, which have been liberated from surrounding material. Our computations are based on the so-called Axion Quark Nugget (AQN) dark matter model, which was originally invented long ago to explain the similarity between the dark an…
The Pierre Auger Observatory have reported [1-3] observation of several exotic cosmic ray -like events which apparently related to thunderstorms. These events are much larger in size than conventional cosmic ray events, and they have very distinct timing features. A possible nature of the observed phenomenon is still a matter of active research and debates as many unusual features of these exotic events are hard to explain. In particular, the frequency of appearance of these exotic events is very low (less than 2 events/year), in huge contrast with a typical rate of a conventional lightning st…
We consider a dark matter (DM) model offering a very natural explanation of the observed relation, $Ω_{\rm dark} \sim Ω_{\rm visible}$. 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, $Λ_{\rm QCD}$. The focus of the present work is the detail study of the dynamics of the $\cal{CP}$-odd coherent axion field $a(x)$ just before the QCD transition. We argue that…
We revisit the properties of positron cloud in quark nugget (QN) model of dark matter (DM). In this model, dark matter particles are represented by compact composite objects composed of a large number of quarks or antiquarks with total baryon number $B\sim 10^{24}$. These particles have a very small number density in our galaxy which makes them "dark" to all DM detection experiments and cosmological observations. In this scenario, anti-quark nuggets play special role because they may manifest themselves in annihilation with visible matter. We study electron-positron annihilation in collisions …
We reexamine the surface composition of strange stars. Strange quark stars are hypothetical compact stars which could exist if strange quark matter was absolutely stable. It is widely accepted that they are characterized by an enormous density gradient ($~10^{26}$ g/cm$^4$) and large electric fields at surface. By investigating the possibility of realizing a heterogeneous crust, comprised of nuggets of strange quark matter embedded in an uniform electron background, we find that the strange star surface has a much reduced density gradient and negligible electric field. We comment on how our fi…
We consider axions coupled to nucleons and photons only through the nucleon electric-dipole moment (EDM) portal. This coupling is a model-independent feature of QCD axions, which solve the strong CP problem, and might arise as well in more general axion-like particle setups. We revise the supernova (SN) axion emission induced by the nucleon EDM coupling and refine accordingly the SN 1987A bound. Furthermore, we calculate the axion flux from a future Galactic SN and show that it might produce a peculiar and potentially detectable gamma-ray signal in a large underground neutrino detector such as…
This paper presents an investigation into the pycnonuclear reaction rates in dense crustal matter of neutron stars contaminated with strange quark matter nuggets. The presence of such nuggets in the crustal matter of neutron stars would be a natural consequence if Witten's strange quark matter hypothesis is correct. The methodology presented in this paper is a recreation of a recent representation of nuclear force interactions embedded within pycnonuclear reaction processes. The study then extends the methodology to incorporate distinctive theoretical characteristics of strange quark matter nu…
It is shown that nuggets of strange quark matter may be extracted from the surface of pulsars and accelerated by strong electric fields to high energies if pulsars are strange stars with the crusts, comprised of nuggets embedded in a uniform electron background. Such high energy nuggets called usually strangelets give an observable contribution into galactic cosmic rays and may be detected by the upcoming cosmic ray experiment Alpha Magnetic Spectrometer AMS-02 on the International Space Station.
We derive the electric current on surface of a normal metal or superconductor induced by the light bosonic dark matter, such as axion or hidden photon, by appropriately taking account of the boundary condition of the electric and magnetic field at the surface. We discuss detection possibility of such an electric current.
We advocate for the idea that there is a fundamentally new mechanism for axion production on Earth, as recently suggested in Fischer et al. (2018) and Liang & Zhitnitsky (2018). We specifically focus on production of axions within Earth, with low velocities such that they will be trapped in the gravitational field. Our computations are based on the so-called Axion Quark Nugget (AQN) dark matter model, which was originally invented to explain the similarity of the dark and visible cosmological matter densities. This occurs in the model irrespective of the axion mass $m_\mathrm{a}$ or initial mi…
We advocate the idea that there is a fundamentally new mechanism for the axion production in the Sun, which has never been discussed previously in the literature. This novel mechanism of the axion production is based on the so-called Axion Quark Nugget (AQN) Dark Matter Model. These axions will be produced in addition to well studied axions emitted due to the Primakoff effect. The AQN model was originally invented as a natural explanation of the observed ratio $Ω_{\rm dark} \sim Ω_{\rm visible}$ when the DM and visible matter densities assume the same order of magnitude values, irrespectively …
Axions may make a significant contribution to the dark matter of the universe. It has been suggested that these dark matter axions may condense into localized clumps, called "axion stars." In this paper we argue that collisions of dilute axion stars with neutron stars, of the type known as "magnetars," may be the origin of most of the observed fast radio bursts. This idea is a variation of an idea originally proposed by Iwazaki. However, instead of the surface effect of Iwazaki, we propose a perhaps stronger volume effect caused by the induced time dependent electric dipole moment of neutrons.
In the recent work arXiv:1809.02446, the authors proposed a new method measuring the electron oscillating electric dipole moment (eOEDM) using atomic magnetomaters. This eOEDM is induced by the interaction between the electron magnetic dipole moment, electric field and axion field. The result is sensitive to the axion-photon coupling according to [Hill, PRD 91, 111702 (2015)]. Here we want to describe that the same experimental method can be also sensitive to the axion-electron coupling according to [Alexander and Sims, PRD 98, 015011 (2018)]. In this article, we will show the corresponding se…
We explore the axionic dark matter search sensitivity with a narrow-band detection scheme aiming at the axion-photon conversion by the static electric field inside a cylindrical capacitor. An alternating magnetic field signal is induced by effective currents as the axion dark matter flows perpendicularly through the electric field. At low axion masses, like in a KKLT scenario, front-end narrow band filtering is provided by using LC resonance with a high $Q$ factor, which enhances the detectability of the tiny magnetic field signal and also leads to a thermal noise as the major background that …
We show for the classical Maxwell equations, including the axion electromagnetic anomaly source term, that a cosmic axion field induces an oscillating electric N-moment for any static magnetic N-moment. This is a straightforward result, accessible to anyone who has taken a first year graduate course in electrodynamics.
We propose to search for axion dark matter via the oscillating electric dipole moments that axions induce in atoms and molecules. These moments are produced through the intrinsic oscillating electric dipole moments of nucleons and through the $P,T$-violating nucleon-nucleon interaction mediated by pion exchange, both of which arise due to the axion-gluon coupling, and also directly through the axion-electron interaction. Axion dark matter may also be sought for through the spin-precession effects that axions produce by directly coupling to fermion spins.
The coupling between axions and photons modifies Maxwell's equations, introducing a dynamo term in the magnetic induction equation. In neutron stars, for critical values of the axion decay constant and axion mass, the magnetic dynamo mechanism increases the total magnetic energy of the star. We show that this generates substantial internal heating due to enhanced dissipation of crustal electric currents. These mechanisms would lead magnetized neutron stars to increase their magnetic energy and thermal luminosity by several orders of magnitude, in contrast to observations of thermally-emitting …
We study the pair production of fermions in a time dependent axion background with and without an electric background. We construct the adiabatic mode functions which incorporate the gauge field and the axion velocity dependence of the dispersion relation. The semiclassical approach using this adiabatic basis shows two types of pair production. One is axion-assisted pair production: the presence of the axion velocity gives enhancement and interference effects on the pair production driven by the electric field. The other is axion-driven pair production: the time variation of the axion velocity…
We report on a search for ultra-low-mass axion-like dark matter by analysing the ratio of the spin-precession frequencies of stored ultracold neutrons and $^{199}$Hg atoms for an axion-induced oscillating electric dipole moment of the neutron and an axion-wind spin-precession effect. No signal consistent with dark matter is observed for the axion mass range $10^{-24}~\textrm{eV} \le m_a \le 10^{-17}~\textrm{eV}$. Our null result sets the first laboratory constraints on the coupling of axion dark matter to gluons, which improve on astrophysical limits by up to 3 orders of magnitude, and also im…
Detecting axionic dark matter induced electron or nucleon oscillating electric dipole moment (OEDM) has become a new way for dark matter searches. We re-examine such axion-spin couplings in external electromagnetic fields. We point out that axion-photon interaction induces an electron spin effective coupling, which is different from an OEDM. In particular, the axion-spin effective coupling is directly related to magnetic field rather than electric field. For axion-electron or axion-nucleon couplings, an OEDM of fermion is introduced, whose effect in ultralight axion cases depends on whether ax…
In the recent work [Phys. Rev. D 91, 111702(R) (2015)], C. Hill concludes that the axion electromagnetic anomaly induces an oscillating electron electric dipole moment of frequency $m_a$ and strength $\sim 10^{-32}~e$ cm, in the limit $v/c \to 0$ for the axion field. Here, we demonstrate that a proper treatment of this problem in the lowest order yields $\textit{no}$ electric dipole moment of the electron in the same limit. Instead, oscillating electric dipole moments of atoms and molecules are produced by different mechanisms.
We have proposed a method for the detection of dark matter axion. It uses superconductor under strong magnetic field. As is well known, the dark matter axion induces oscillating electric field under magnetic field. The electric field is proportional to the magnetic field and makes charged particles oscillate in conductors. Then, radiations of electromagnetic fields are produced. Radiation flux depends on how large the electric field is induced and how large the number of charged particles is present in the conductors. We show that the electric field in superconductor is essentially identical t…
The axion electromagnetic anomaly induces an oscillating electric dipole for {\em any} static magnetic dipole. Static electric dipoles do not produce oscillating magnetic moments. This is a low energy theorem which is a consequence of the space-time dependent cosmic background field of the axion in the limit that it is only locally time dependent $(\overrightarrowβ=0)$. The electron will acquire an oscillating electric dipole of frequency $m_a$ and strength $\sim 10^{-32}$ e-cm, three orders of magnitude above the nucleon, and within four orders of magnitude of the present standard model DC li…
A general axion-electrodynamic formalism is presented on the phenomenological level when the environment is dielectric (permittivity and permeability assumed to be constants). Thereafter, a strong and uniform magnetic field is considered in the $z$ direction, the field region having the form of a long material cylinder (which corresponds to the haloscope setup). If the axion amplitude depends on time only, the axions give rise to an oscillating electric current in the $z$ direction. We estimate the magnitudes of the azimuthal magnetic fields and the accompanying Joule heating in the cylinder, …
Recently there has been a surge of new experimental proposals to search for ultra-light axion dark matter with axion mass, $m_a\lesssim1\,μ$eV. Many of these proposals search for small oscillating magnetic fields induced in or around a large static magnetic field. Lately, there has been interest in alternate detection schemes which search for oscillating electric fields in a similar setup. In this paper, we explicitly solve Maxwell's equations in a simplified geometry and demonstrate that in this mass range, the axion induced electric fields are heavily suppressed by boundary conditions. Unfor…
In the world with axion the precise measurement of gravitational force and check of the equivalence principle at small distances, $λ\sim 1cm$ and less, could provide an additional test of CP symmetry. Using the chiral approach, we connect the strength of CP-odd axion-nucleon vertex with CP-odd pion-nucleon coupling for color electric dipole moments of quarks as a low energy source of CP violation. Strong limits on CP-odd coupling $g_{πNN}$ coming from atomic electric dipole moments show that gravitational experiments are six orders of magnitude away from the sensitivity level needed to detect …
