Axion-like Particles Research Articles

Di-Higgs production via axion-like particles

Due to the pseudo-scalar nature of the axion-like particle (ALP), the CP-conserving production of two Higgs bosons via the ALP necessarily involves an additional Z or γ boson. We examine the existing constraints from di-Higgs searches at Run 2 of the LHC and find that, despite the presence of extra objects in the final state, these searches are sensitive to a combination of ALP couplings to gluons and three-bosons in the TeV scale range. Additionally, we propose a specialized search strategy incorporating an energetic leptonic Z boson. This refined ALP-induced production process would allow for the identification of the h h → 4 b-jet final state and could potentially probe the TeV scale using data from Run 2 of the LHC. This production process can also occur through a coupling between the top quark and the ALP. We translate the current constraints on di-Higgs production into new limits on the ALP-top coupling.

Bounds on ALP-mediated dark matter models from celestial objects

We have studied the signals from axion-like particles (ALPs) as dark matter mediators from celestial objects such as neutron stars, brown dwarfs or white dwarfs. We consider the accumulation of dark matter inside the celestial objects using the multiscatter capturing process. The production of ALP from the dark matter annihilation can escape the celestial object and decay into gamma-rays and neutrinos before reaching the Earth. We investigate our model using gamma-ray observations from Fermi and H.E.S.S. and neutrino observations from IceCube and ANTARES. The effective Lagrangian approach allows us to place constraints on the ALP-photon and ALP-fermion couplings. In the gamma-ray channel, our results are able to rule out the existence of ALP with mass up to ~ O\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\mathcal{O} $$\\end{document}(10) GeV. On the other hand, the neutrino observations can be used to probe a higher mass range with ALP mass up to ~ O\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\mathcal{O} $$\\end{document}(100) GeV.

Probing axion-like particles in leptonic decays of heavy mesons

Abstract We study the possibility to find the axion-like particles (ALPs) through the leptonic decays of heavy mesons. The Standard Model (SM) predictions of the branching ratios of the leptonic decays of heavy mesons are less than corresponding experimental upper limits. This provides some space for the existence of decay channels where the ALP is one of the products. Three scenarios are considered: first, the ALP is only coupled to one single charged fermion, namely, the quark, the antiquark, or the charged lepton; second, the ALP is only coupled to quark and antiquark with the same strength; third, the ALP is coupled to all the charged fermions with the same strength. The constraints of the coupling strength in different scenarios are obtained by comparing the experimental data of the branching ratios of leptonic decays of $B^-$, $D^+$, and $D_s^+$ mesons with the theoretical predictions which are achieved by using the Bethe-Salpeter (BS) method. These constraints are further applied to predict the upper limits of the leptonic decay processes of the $B_c^-$ meson in which the ALP participates.Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.

Searching for long-lived light neutralinos and axionlike particles at the SHiNESS experiment

Recently, Soleti [] proposed a new experiment called SHiNESS at the upcoming European Spallation Source (ESS) facility, making use of the 2-GeV proton beam there impinging on a fixed target, in order to search for hidden sterile neutrinos that could lie in different mass ranges and arise with distinct signatures. Such signatures include excesses in electron-positron pairs that may originate from displaced decays of long-lived particles (LLPs). At the ESS, the dominant sources of such LLPs are decays at rest of π+ mesons and μ+ leptons. We choose to investigate theoretical scenarios of long-lived light neutralinos in the R-parity-violating supersymmetry and long-lived weak-violating electrophilic axionlike particles, as these LLPs can be produced from decays of π+ and μ+. Since the π+’s and μ+’s decay at rest at the ESS, we compute the spectra of the therefrom produced LLPs and thus estimate the expected sensitivity reach of SHiNESS to the LLPs in these two scenarios. Our calculation shows that in multiple relevant benchmark scenarios, SHiNESS can probe large parameter regions of these models beyond the existing bounds, in just a couple of years of data-collection time. Published by the American Physical Society 2024

Echo-free quality factor of a multilayer axion haloscope

We report a methodology to determine the quality factor (Q) of wavy dark matter detectors equipped with multilayered resonators, including Fabry-Pérot interferometers and the so-called dielectric haloscope. 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 and Axionlike Particles Interferometer (DALI) prototype is a few hundred per layer over a sweep bandwidth of a few dozen of megahertz. 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 gaγγ≳10−12 and gaγγ≳few×10−14 GeV−1 at frequencies of several dozens of gigahertz once cooled down to the different working temperatures of the experiment and immersed in magnetic fields ranging from about 1 to 10 T; while the sensitivity of the full-scale DALI is projected at gaγγ≳few×10−15 GeV−1 over the entire 25–250 μeV range since Q≳104 is expected. Published by the American Physical Society 2024

Search for Light Long-Lived Particles in pp Collisions at s=13 TeV Using Displaced Vertices in the ATLAS Inner Detector

A search for long-lived particles (LLPs) using 140 fb−1 of pp collision data with s=13 TeV recorded by the ATLAS experiment at the LHC is presented. The search targets LLPs with masses between 5 and 55 GeV that decay hadronically in the ATLAS inner detector. Benchmark models with LLP pair production from exotic decays of the Higgs boson and models featuring long-lived axionlike particles (ALPs) are considered. No significant excess above the expected background is observed. Upper limits are placed on the branching ratio of the Higgs boson to pairs of LLPs, the cross section for ALPs produced in association with a vector boson, and, for the first time, on the branching ratio of the top quark to an ALP and a u/c quark. © 2024 CERN, for the ATLAS Collaboration 2024 CERN

Searching accretion-enhanced dark matter annihilation signals in the Galactic Centre

This study reanalyzes the detection prospects of dark matter (DM) annihilation signals in the Galactic Center, focusing on velocity-dependent dynamics within a spike density near the supermassive black hole (Sgr A⋆). We investigate three annihilation processes — p-wave, resonance, and forbidden annihilation — under semi-relativistic velocities, leveraging gamma-ray data from Fermi and DAMPE telescopes. Our analysis integrates a fermionic DM model with an electroweak axion-like particle (ALP) portal, exploring annihilation into two or four photons. Employing a comprehensive six-dimensional integration, we precisely calculate DM-induced gamma-ray fluxes near Sgr A⋆, incorporating velocity and positional dependencies in the annihilation cross-section and photon yield spectra. Our findings highlight scenarios of resonance and forbidden annihilation, where the larger ALP-DM-DM coupling constant Caχχ can affect spike density, potentially yielding detectable gamma-ray line spectra within Fermi and DAMPE energy resolution. We set upper limits for Caχχ across these scenarios, offering insights into the detectability and spectral characteristics of DM annihilation signals from the Galactic Center.

Enhanced early galaxy formation in JWST from axion dark matter?

We demonstrate that enhanced early galaxy formation can generically arise in axion-like particle (ALP) dark matter (DM) models with a delayed onset of axion field oscillation. In these models, the formation of localized massive objects enhances structure formation, potentially addressing the excess recently observed by the James Webb Space Telescope (JWST), while remaining consistent with existing constraints. We identify viable parameter space with the ALP mass in the range of 10−22eV<ma<10−19eV. In addition, we show that the ALP parameter regions of interest can lead to intriguing complementary signatures in the small scale structure of DM halos and existing experimental searches for ALPs.

Prospects for detecting the couplings of axion-like particle with neutrinos at the CEPC

AbstractWe explore the possibility of detecting the couplings of axion-like particle (ALP) with leptons from their loop-level impact on the ALP couplings to electroweak (EW) gauge bosons via the signal process "Equation missing" at the circular electron positron collider (CEPC) and obtain prospective sensitivities to the ALP-lepton couplings. Our numerical results show that the CEPC with the center of mass energy $$\sqrt{s}=240~(91)$$ s = 240 ( 91 ) GeV and the integrated luminosity $$\mathcal {L}=5.6~(16)$$ L = 5.6 ( 16 ) $$\hbox {ab}^{-1}$$ ab - 1 might be sensitive for probing the ALP-lepton couplings in the ALP mass range from 10 GeV to 130 (50) GeV, where the prospective sensitivities to the ALP-neutrino coupling $$Tr(g_{a\nu \nu })/f_a$$ T r ( g a ν ν ) / f a can be as low as 0.016 (0.012) $$\hbox {GeV}^{-1}$$ GeV - 1 and $$0.0031~(2.8 \times 10^{-4})$$ 0.0031 ( 2.8 × 10 - 4 ) $$\hbox {GeV}^{-1}$$ GeV - 1 for $$c_{R}=0$$ c R = 0 and $$c_{R}=c_{L}$$ c R = c L , and to the ALP-charged lepton coupling $$Tr(g_{a\ell \ell })/f_a$$ T r ( g a ℓ ℓ ) / f a can be as low as 0.035 (0.07) $$\hbox {GeV}^{-1}$$ GeV - 1 for $$c_{L}=0$$ c L = 0 . We find that the prospective sensitivities given by the CEPC are not covered by the current and expected exclusion regions in some ALP mass intervals. The CEPC has the potential for exploring the ALP-neutrino couplings via some promising processes induced by the ALP-EW gauge boson couplings in the future.

Generalising axion-like particle as the curvaton: sourcing primordial density perturbation and non-Gaussianities

We investigate the non-perturbatively generated axion-like particle (ALP) potential, involving fermions in the dark sector that couple to the ALP, in an early universe cosmological inflationary stage with the ALP being a spectator field. The potential here deviates from the standard cosine nature due to the presence of the two dark sector fermion masses mu\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_u$$\\end{document} and md\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_d$$\\end{document} which couple to the ALP. The ALP is a spectator field during inflation but it starts to oscillate and dominates the energy density of the universe after inflation ends, thereby sourcing isocurvature perturbations, while standard curvature fluctuations from the inflaton are assumed to be sub-dominant. Subsequently the ALP decays converting the isocurvature perturbations to adiabatic perturbations thereby acting as the origin of the primordial density perturbations. We identify the parameter space involving the axion decay constant fϕ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$f_{\\phi }$$\\end{document}, scale of confinement Λ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\Lambda $$\\end{document}, ALP mass m and the masses of the fermions, mu\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_u$$\\end{document} and md\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_d$$\\end{document} where it can satisfactorily behave as the curvaton and source the observed primordial density perturbation. We also predict local non-Gaussianity signals for bi-spectrum and tri-spectrum fNL\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$f_{NL}$$\\end{document} and gNL\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$g_{NL}$$\\end{document}, as a function of the ratio mu/md\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_u/m_d$$\\end{document}, which are within the allowed range in the latest Planck observations and are detectable with future observations. Particularly we find that the value of fNL\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$f_{NL}$$\\end{document} and gNL\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$g_{NL}$$\\end{document} are dependent on the ratio of mu\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_u$$\\end{document} and md\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_d$$\\end{document}: fNL\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$f_{NL}$$\\end{document} is more or less positive for all scenarios except mu=md\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_u = m_d$$\\end{document} and gNL\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$g_{NL}$$\\end{document} is always positive irrespective of the ratio between mu\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_u$$\\end{document} and md\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_d$$\\end{document}. The results of our analysis in the limit mu=md\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_u = m_d$$\\end{document} resembles vanilla curvaton scenario while in the limit mu≫md\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_u \\gg m_d$$\\end{document} resembles pure axion cosine potential. This is because the model has the unique feature where the extra matter in the dark sector determines the nature and shape of the potential.

Sensitivity to kaon decays to ALPs at fixed target experiments

We study the sensitivity of fixed target experiments to hadronically coupled axionlike particles (ALPs) produced in kaon decays, with a particular emphasis on current and upcoming Short-Baseline Neutrino (SBN) experiments. We demonstrate that below the kaon decay mass threshold (ma&lt;mK−mπ) kaon decay is the dominant production mechanism for ALPs at neutrino experiments, larger by many orders of magnitude than production in pseudoscalar mixing. Such axions can be probed principally by the diphoton and dimuon final states. In the latter case, even if the axion does not couple to muons at tree level, such a coupling is induced by the renormalization group flow from the UV scale. We reinterpret prior results by CHARM and MicroBooNE through these channels and show that they constrain new areas of heavy axion parameter space. We also show projections of the sensitivity of the SBN experiment and Deep Underground Neutrino Experiment (DUNE) to axions through these channels, which reach up to a decade higher in the axion decay constant beyond existing constraints. DUNE projects to have a sensitivity competitive with other world-leading upcoming experiments. Published by the American Physical Society 2024

Detecting axion dark matter with chiral magnetic effects

We show that dark matter axions or axionlike particles (ALP) induce spontaneously alternating electric currents in conductors along the external magnetic fields due to the (medium) axial anomaly, realizing the chiral magnetic effects (CME). We propose a new experiment to measure this current to detect the dark matter axions or ALP. These induced currents are the electron medium effects, directly proportional to the axion or ALP coupling to electrons, which depends on their microscopic physics. In the experimental setup, one measures the sum of the electric current due to CME and the vacuum current due to the anomalous axion-photon coupling. The CME current is, in general, subdominant by a factor of the Fermi velocity of electrons, compared to latter, unless the axion or ALP coupling to electrons is much bigger than its coupling to photons to compensate the Fermi velocity suppression. However, we find that repurposing the currently operating and planned axion haloscopes may have good sensitivity to probe the CME current. Published by the American Physical Society 2024

Froggatt-Nielsen ALP

The Froggatt-Nielsen (FN) mechanism, a prominent framework for explaining the observed flavor hierarchies, generically predicts the existence of an axion-like particle (ALP). This work examines a class of FN models based on ℤN discrete symmetries. We chart the allowed parameter space from a set of theoretical considerations and construct explicit renormalizable completions with minimal field content necessary to generate consistent textures. We then conduct comprehensive phenomenological analyses of two particularly elegant ℤ4 and ℤ8 models, highlighting the interplay between the effects of the ALP and the associated UV fields. We find that the FN scale can be as low as a few TeV.

New physics at a neutron beam dump

We find a new utility of neutrons, usually treated as an experimental nuisance causing unwanted background, in probing new physics signals. The new physics signals can either be radiated from neutrons (neutron bremsstrahlung) or appear through secondary particles from neutron-on-target interactions, dubbed “neutron beam dump.” As a concrete example, we take the FASER/FASER2 experiment as a “factory” of high-energy neutrons that interact with the iron dump. We find that if new physics particles had the same interaction strength to protons and neutrons, their production rate via neutron-initiated bremsstrahlung would be comparable to that via proton-initiated ones, in terms of the resulting flux and the range of couplings that can be probed. The neutron bremsstrahlung can be used, for instance, to probe dark gauge bosons with nonzero neutron coupling. In particular, we investigate protophobic gauge bosons and find that FASER/FASER2 can probe new parameter space. We also illustrate the possibility of neutron-induced secondary particles by considering axionlike particles with electron couplings. We conclude that the physics potential of FASER/FASER2 in terms of new physics searches can be greatly extended and improved with the inclusion of neutron interactions. Published by the American Physical Society 2024

Editorial: New developments in the quest for discovering axions and axion-like particles

Editorial: New developments in the quest for discovering axions and axion-like particles

Exploring interference effects between two ALP effective operators at the LHC

We observe that most studies of axion-like particle (ALP) production channels at the Large Hadron Collider (LHC) focus on a single type of ALP operator for each process in the effective field theory framework. In this work, we propose an alternative approach that considers two or more types of relevant ALP effective operators together in some specific ALP production channels and study their interference effects. Using the pp → tja process with a → γγ as an example, we show that this approach allows us to constrain the ALP interactions with both the W boson and the top quark, as well as their interference in a single process. For the final state with two isolated photons and a top quark decaying semi-leptonically, we predict that the future bounds on the ALP decay constant can reach around fa ~ 10 (20) TeV for 25 GeV < Ma < 100 GeV at the LHC with 300 (3000) fb−1 luminosity.

Constraints on Metastable Dark Energy Decaying into Dark Matter

We revisit the proposal that an energy transfer from dark energy into dark matter can be described in field theory by a first order phase transition. We analyze a metastable dark energy model proposed in the literature, using updated constraints on the decay time of a metastable dark energy from recent data. The results of our analysis show no prospects for potentially observable signals that could distinguish this scenario from the ΛCDM. We analyze, for the first time, the process of bubble nucleation in this model, showing that such model would not drive a complete transition to a dark matter dominated phase even in a distant future. Nevertheless, the model is not excluded by the latest data and we confirm that the mass of the dark matter particle that would result from such a process corresponds to the mass of an axion-like particle, which is currently one of the best motivated dark matter candidates. We argue that extensions to this model, possibly with additional couplings, still deserve further attention as it could provide an interesting and viable description for an interacting dark sector scenario based in a single scalar field.

Exploring axionlike particle couplings through single top tW -channel and top pair production at the LHC

In this paper, we explore the interactions between light axionlike particles (ALPs) and top quarks, gluons, and W-bosons. Utilizing high-energy probes at the LHC, we probe these couplings in the context of single top quark production associated with a W-boson and an ALP. We analyze the latest LHC Run II data on tt¯ spin correlation measurements to establish constraints on these couplings. Additionally, we compare these constraints with those derived from loop-induced couplings and indirect searches involving B-meson decays. Furthermore, we derive two-dimensional limits on the ALP couplings with top quarks and gluons. Published by the American Physical Society 2024

Unveiling the early universe: Axion-like particles and their role in primordial structure formation

Unveiling the early universe: Axion-like particles and their role in primordial structure formation

First Results from the Axion Dark-Matter Birefringent Cavity (ADBC) Experiment.

Axions and axionlike particles are strongly motivated dark-matter candidates that are the subject of many current ground based dark-matter searches. We present first results from the Axion Dark-Matter Birefringent Cavity (ADBC) experiment, which is an optical bow-tie cavity probing the axion-induced birefringence of electromagnetic waves. Our experiment is the first optical axion detector that is tunable and quantum noise limited, making it sensitive to a wide range of axion masses. We have iteratively probed the axion mass ranges 40.9-43.3 neV/c^{2}, 49.3-50.6 neV/c^{2}, and 54.4-56.7 neV/c^{2}, and found no dark-matter signal. On average, we constrain the axionlike particle and photon coupling at the level g_{aγγ}≤1.9×10^{-8} GeV^{-1}. We also present prospects for future axion dark-matter detection experiments using optical cavities.