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Konstantin Zioutas

Publications and source records attributed to Konstantin Zioutas.

At least 19 recordsLinked to original sources

Constraints on Galactic Dark Photons from a DALI Prototype

An analysis of 36 hours of data from a DALI haloscope reveals no statistically significant excess attributable to dark-photon dark matter. We therefore set new constraints in the 6.88691--6.91792 GHz band, reaching a dark-photon-to-photon kinetic mixing strength of $χ\lesssim 6.8\times10^{-14}$ at $28.54 \, μ\mathrm{eV}$. To our knowledge, this result established the strongest laboratory-based exclusion limit in this frequency range.

hep-ex

The DALI Haloscope: A Magnetized Phased Array Coupled to a Semi-Open Fabry--Pérot Resonator

DALI is an axion haloscope consisting of a magnetized phased array backed by a conducting mirror and coupled in the near field to a semi-open Fabry--Pérot resonator. The applied static magnetic field makes both the dielectric interfaces and the conducting mirror sensitive to axion-induced electromagnetic conversion. Each interface acts as a radiating surface, and the resulting fields are projected onto the mode collected by the resonator and delivered to the receiver. We derive the detected power in terms of the power available from the magnetized mirror, the coherent contribution of the dielectric interfaces, the transverse mode overlap, the loaded quality factor, and the receiver-coupling coefficient. This formulation separates two distinct enhancement mechanisms. The dielectric-interface emissions may add coherently, producing a dielectric boost, while the semi-open Fabry--Pérot resonator provides enhancement through resonant storage of the coupled electromagnetic field. These contributions depend differently on the dielectric thicknesses, spacings, and resonant mode, and should therefore be evaluated independently. The same assembly can operate between the limits of a coherently boosted dielectric haloscope and a mirror-sourced, resonantly enhanced Fabry--Pérot haloscope. This combined architecture offers a flexible approach to resonant axion searches at frequencies for which conventional closed microwave cavities become increasingly limited in conversion volume.

hep-ex

Superfluid He-4 as Dark Matter Detectors

Superfluid helium-4 is an attractive medium for high-sensitivity detection of dark matter (DM) candidates (as well as other particles). There are several collaborations that have built and tested superfluid helium detectors, particularly focusing on the sub-GeV DM mass range. In this paper we discuss a novel idea for detecting Axion (Anti)Quark Nuggets (AQN) by using parasitically the superfluid helium-4 LHC cooling system as a unique large-scale earth bound DM detector. In the case of the AQN, we address the question of propagation in the metal parts surrounding the helium. An AQN induces significant heating around the propagation track that damages the enclosure.

hep-ph

A New Way to Detect Axions from $\rm{A\bar{Q}Ns}$ Captured in the Earth

Macroscopic dark matter with dominating strong interactions, supposed to be composites, represents an alternative to the most popular WIMP particles. Predicted in various models as strangelets, nuclearites, nuggets, having different internal structures and properties, but not yet observed experimentally, these forms of dark matter are associated with the existence of a large number of still unexplained observations. Nuggets, initially predicted by Witten, were reconsidered from the point of view of their internal structure and further theorized in 2003 by Zhitnitsky as axion quark nuggets and axion antiquark nuggets, as being made of quarks in a superconducting colour state, in the core, an electrosphere of electrons or positrons and a domain wall that maintain the stability of the macros with an incredible density, mass in the gram range and radius on the order of micrometers. If the existence of $\rm{AQNs}$ and $\rm{A\bar{Q}Ns}$ is demonstrated, two major open problems in physics could be addressed simultaneously: they would constitute viable dark matter candidates and, at the same time, provide a natural mechanism for restoring matter-antimatter symmetry in the Universe. The experimental evidence of the $\rm{AQNs}$ and $\rm{A\bar{Q}Ns}$ is a challenge for current and future experiments. The present study demonstrates that if these macroscopic systems exist, axions produced by $\rm{A\bar{Q}N}$s could be detected by the next generation of neutrino physics experiments using liquid noble gases, due to their huge active volumes.

hep-ph

First Limits on Axion Dark Matter from a DALI Prototype

We report a pilot dark-matter search with a cryogenic, magnetized, scaled-down DALI prototype. An analysis of 36 hours of data reveals no statistically significant excess attributable to axionlike particles. We therefore set new exclusion limits in the 6.883--6.920 GHz band, reaching an axion-photon coupling sensitivity of $g_{aγγ}\lesssim 1.27\times10^{-11}\,\mathrm{GeV}^{-1}$ at 28.54 $μ$eV. These results consolidate the DALI approach and motivate a next-stage haloscope to explore a broader mass range with upgraded instrumentation.

hep-ex

Status of the Proton EDM Experiment (pEDM)

The Proton EDM Experiment (pEDM) is the first direct search for the proton electric dipole moment (EDM) with the aim of being the first experiment to probe the Standard Model (SM) prediction of any particle EDM. Phase-I of pEDM will achieve $10^{-29} e\cdot$cm, improving current indirect limits by four orders of magnitude. This will establish a new standard of precision in nucleon EDM searches and offer a unique sensitivity to better understand the Strong CP problem. The experiment is ideally positioned to explore physics beyond the Standard Model (BSM), with sensitivity to axionic dark matter via the signal of an oscillating proton EDM and across a wide mass range of BSM models from $\mathcal{O}(1\text{GeV})$ to $\mathcal{O}(10^3\text{TeV})$. Utilizing the frozen-spin technique in a highly symmetric storage ring that leverages existing infrastructure at Brookhaven National Laboratory (BNL), pEDM builds upon the technological foundation and experimental expertise of the highly successful Muon $g$$-$$2$ Experiments. With significant R\&D and prototyping already underway, pEDM is preparing a conceptual design report (CDR) to offer a cost-effective, high-impact path to discovering new sources of CP violation and advancing our understanding of fundamental physics. It will play a vital role in complementing the physics goals of the next-generation collider while simultaneously contributing to sustaining particle physics research and training early-career researchers during gaps between major collider operations.

hep-ex

Echo-free quality factor of a multilayer axion haloscope

We report a methodology to determine the quality factor ($Q$) in implementations of the so-called dielectric haloscope, a new concept of wavy dark matter detector equipped with a multilayered resonator. An anechoic chamber enables the observation of the resonance frequency and its amplitude for an unlimited series of layers for the first time, which is conveniently filtered. The frequency-normalized power enhancement measured in a Dark-photons \& Axion-Like particles Interferometer (DALI) prototype is a few hundred per layer over a sweep bandwidth of half a hundred MHz. In light of this result, this scaled-down prototype is sensitive to axions saturating the local dark matter density with a coupling to photons between $g_{aγγ}\gtrsim10^{-12}$ GeV$^{-1}$ and $g_{aγγ}\gtrsim$ few $\times 10^{-14}$ GeV$^{-1}$ at frequencies of several dozens of GHz once cooled down to the different working temperatures of the experiment and immersed in magnetic fields ranging from 1 T to 10 T; while the sensitivity of the full-scale DALI is projected at $g_{aγγ}\gtrsim\mathrm{few}\times10^{-15}$ GeV$^{-1}$ over the entire 25--250 μeV range since $Q\gtrsim10^4$ is expected.

hep-ex

DALI sensitivity to streaming axion dark matter

Dark matter substructures emerge naturally in a scenario in which the axion angular field acquires propagating degrees of freedom in a post-inflationary Universe. The DALI experiment is a new generation wavy dark matters interferometer currently in prototyping. Although DALI's main objective is to explore the virialized DM in our Galaxy, to a large degree in this article we explore the prospect for detection of fine grained streams made of axions that would enter the Solar System, as suggested by previous work. We find that DALI will have a sensitivity to encounters with these coherent objects that fully spans the window defined by the coupling strength to photons of representative axion models over a stacked bandwidth of two decades in mass.

hep-ph

Gravitational focusing effects on streaming dark matter as a new detection concept

Cosmological simulations for cold dark matter (DM) indicate that a large number of streams might exist in our Galaxy. The present work incorporates gravitational focusing (GF) effects on streaming DM constituents by the Sun and the Earth preceding their encounter with Earth bound detectors. For streaming DM, the GF gives rise to spatiotemporal flux enhancements of orders of magnitude above the nominal DM density. Remarkably, due to Earth's rotation the derived flux enhancements appear as transient signals lasting about 10 seconds repeating daily for days or weeks. This work presents a novel opportunity for DM signal detection and identification, and the present simulation can be applied to any kind of invisible matter entering the solar system.

astro-ph.IM

Planetary relationships to birth (imputed conception) rates in humans: A signature of cosmic origin?

Planetary effects have been attributed to biological processes without scientific rigor. Some generic invisible slow matter from the dark Universe in the form of streams or clusters with occasional large flux enhancements due to planetary gravitational focusing is the driving idea and the only explanation we have. This work extends previous observations regarding relationships of diagnosed cancer (melanoma), which may provide additional insight into previously unrecognized factors also affecting other biological processes. Biological measurements in vitro and mutation rates are promising.

physics.med-ph

Searching for axion streams with the echo method

The axion dark matter echo technique, proposed in Ref. [1], aims to search for axion dark matter by detecting the electromagnetic echo coming from stimulated decay of ambient axion dark matter interacting with a radio-microwave outgoing beam. In this work we consider deviations from the standard halo model (SHM) in the form of fine grained streams that are present in the solar system and use them as a target for the axion echo method, which demonstrates to be very sensitive to particular local axion dark matter phase space distributions. We show that the extremely small dispersion of the streams works in favor of the echo method performance, improving its sensitivity in the axion-photon coupling up to two orders of magnitude, with respect to the isotropic SHM. We also discuss the possibility of targeting high density dark matter hairs formed when fine grained streams focus by the inner Earth's gravitational field.

hep-ph

The storage ring proton EDM experiment

We describe a proposal to search for an intrinsic electric dipole moment (EDM) of the proton with a sensitivity of \targetsens, based on the vertical rotation of the polarization of a stored proton beam. The New Physics reach is of order $10^~3$TeV mass scale. Observation of the proton EDM provides the best probe of CP-violation in the Higgs sector, at a level of sensitivity that may be inaccessible to electron-EDM experiments. The improvement in the sensitivity to $θ_{QCD}$, a parameter crucial in axion and axion dark matter physics, is about three orders of magnitude.

hep-ph

On the origin of the rhythmic Sun's radius variation

The Sun shrinks during solar maximum and regrows during solar minimum by a few kilometers. Here, we observe, for the first time, that the solar radius variation shows planetary relationship. This suggests that some remote planetary links must exist, even though this is unexpected within known physics. Therefore, we speculate about its cause, which is the driving idea behind this investigation. Namely, it must be some generic as yet invisible streaming matter from the dark Universe. The associated energy change is massive although it extends from months to several years. The impact by the tentative invisible massive matter accumulates with time, triggering slowly the underlying processes. This study shows that the sun size response is as short as a few months. Then, the solar system is the target and the antenna of still unidentified external impact, assuming to be from the dark sector.

physics.gen-ph

Gaia, Fundamental Physics, and Dark Matter

The Gaia space astrometry mission is measuring accurate distances and space motions of more than two billion stars throughout our Galaxy and beyond. This is a first look at how Gaia is contributing to fundamental physics, and in particular to our understanding of dark matter, for which a few examples are given from the current literature. One of our goals is to illustrate how deep, and often surprising, insight into very diverse areas of fundamental physics can be extracted from this new and enormous high-accuracy stellar data set. In this spirit, we finish by suggesting a search for a connection between stellar activity, dark matter streams, and planetary configuration in nearby exoplanetary systems, as has been tentatively proposed in the case of the solar system.

astro-ph.GA

RESPONSE TO Time Modulations and Amplifications in the Axion Search Experiments

In this short note we argue why the conclusions made by the authors of arXiv:1908.04675, related to arXiv:1805.05184 and in particular arXiv:1602.03666 given therein, are incorrect. Nevertheless, we think that the advocated Anti-Quark Nuggets are good candidates for the dark Universe, and therefore they deserve further attention.

hep-ph

Comment On the Connection Between Planets, Dark Matter and Cancer, by Hector Socas-Navarro (arXiv:1812.02482 [physics.med-ph])

In arXiv:1812.02482 Socas-Navarro (SN) provided multiple confirmation of the claimed 88 days melanoma periodicity. This greatly strengthens the observation by Zioutas and Valachovic (ZV). Here we comment on the work by SN, because it objects the interpretation of the observation by ZV. Notice that SN objection is based on serious assumptions, which were explicitly excluded by ZV. Further, the conclusion made with a sub-set of data (4 percent) is statistically not significant to dispute ZV. On the contrary, since the same periodicity appears also in other 8 major cancer types, we consider it as a global oscillatory behaviour of cancer. At this stage, such a rather ubiquitous cancer periodicity makes any discussion of a small subset of data at least secondarily. Further, we show here that the 88 days Melanoma periodicity is not related to solar activity. Planetary lensing of streaming low speed invisible massive particles remains the only viable explanation, as it has been introduced previously with a number of physics observations [4]. We also show that planetary lensing of low speed particles cannot be considered in isolation, because of the dominating Sun gravity, at least for the inner planets. Interestingly, gravitational lensing - deflection favours low speed particles.

physics.med-ph

Planetary dependence of melanoma

We present signature for planetary correlations following an analysis of monthly melanoma rates in USA for the period 1973 - 2011. A planetary relationship in medicine is observed for the first time. The statistical significance is well above 5 sigmas, while various crosschecking make systematics highly improbable as the cause. The observed planetary dependence in physics was suggestive for this investigation. Streaming invisible matter from the dark sector, whose flux can be occasionally enhanced towards the Earth via planetary gravitational focusing, and, even much stronger by the Sun, it may be the explanation for 1-10% of melanoma diagnoses. The derived shortest melanoma periodicity of about 87.5 days points in its own right at a short latency period of about few months. Contrariwise, the present findings strengthen the previous physics claim of streams of invisible matter.

physics.med-ph

"Higgs" Factory at the Greek-Turkish Border

We would like to propose the construction of the photon collider based "Higgs factory" in the coming years at the Greek-Turkish border, starting from its test facility with a high energy photon beam. This proposal was among the contributions to the Open Symposium of the ESPG'12.

physics.acc-ph