Search for invisible axion dark matter of mass m$_a=43~μ$eV with the QUAX--$aγ$ experiment
D. Alesini, C. Braggio, G. Carugno, N. Crescini, D. D'Agostino, D. Di Gioacchino, R. Di Vora, P. Falferi, U. Gambardella, C. Gatti, G. Iannone, C. Ligi, A. Lomb… 展开作者
D. Alesini, C. Braggio, G. Carugno, N. Crescini, D. D'Agostino, D. Di Gioacchino, R. Di Vora, P. Falferi, U. Gambardella, C. Gatti, G. Iannone, C. Ligi, A. Lombardi, G. Maccarrone, A. Ortolan, R. Pengo, A. Rettaroli, G. Ruoso, L. Taffarello, S. Tocci
备注：
7 pages, 6 figures. Analysis method changed. The result is almost left unchanged. Consequently, text has been revised in the Analysis section. Added references. Added equations (2), (4), (5)
A haloscope of the QUAX--$aγ$ experiment composed of an oxygen-free high thermal conductivity-Cu cavity inside an 8.1 T magnet and cooled to $\sim200$ mK is put in operation for the search of galactic axion with mass $m_a\simeq43~μ\text{eV}$. The power emitted by the resonant cavity is amplified with a Josephson parametric amplifier whose noise fluctuations are at the standard quantum limit. With the data collected in about 1 h at the cavity frequency $ν_c=10.40176$ GHz, the experiment reaches the sensitivity necessary for the detection of galactic QCD-axion, setting the $90\%$ confidence level limit to the axion-photon coupling $g_{aγγ}<0.639\times10^{-13}$ GeV$^{-1}$.
The QCD axion is an hypothetical particle introduced to solve the strong CP problem of standard model of particle physics and is of interest as a possible component of cold dark matter. In the axion scenario, J.E. Moody and F. Wilczek showed that a new macroscopic long-range force, mediated by axion exchange, acts on electron spins, and that such force can be described in terms of an effective magnetic field. The QUAX-g$_p$g$_s$ experiment, carried out at INFN Laboratori Nazionali di Legnaro, is designed to search for the effects on magnetized samples of the effective field produced by unpolar…
We present a proposal to search for QCD axions with mass in the 200 $μ$eV range, assuming that they make a dominant component of dark matter. Due to the axion-electron spin coupling, their effect is equivalent to the application of an oscillating rf field with frequency and amplitude fixed by the axion mass and coupling respectively. This equivalent magnetic field would produce spin flips in a magnetic sample placed inside a static magnetic field, which determines the resonant interaction at the Larmor frequency. Spin flips would subsequently emit radio frequency photons that can be detected b…
Axions, originally proposed to solve the strong CP problem of quantum chromodynamics, emerge now as leading candidates of WISP dark matter. The rich phenomenology associated to the light and stable QCD axion can be described as an effective magnetic field that can be experimentally investigated. For the QUAX experiment, dark matter axions are searched by means of their resonant interactions with electronic spins in a magnetized sample. In principle, axion-induced magnetization changes can be detected by embedding a sample in an rf cavity in a static magnetic field. In this work we describe the…
A haloscope of the QUAX--$aγ$ experiment, composed of an high-Q resonant cavity immersed in a 8 T magnet and cooled to $\sim 4.5$~K is operated to search for galactic axion with mass $m_a\simeq42.8~μ\text{eV}$. The design of the cavity with hollow dielectric cylinders concentrically inserted in a OFHC Cu cavity, allowed us to maintain a loaded quality-factor Q $\sim 300000$ during the measurements in presence of magnetic field. Through the cavity tuning mechanism it was possible to modulate the resonance frequency of the haloscope in the region $10.35337-10.35345$~GHz and thus acquire differen…
We present a more stringent upper limit on long-range axion-mediated forces obtained by the QUAX-g$_p$g$_s$ experiment, located at the INFN - Laboratori Nazionali di Legnaro. We investigate the possible coupling between the electron spins of a paramagnetic GSO crystal and unpolarized nucleons of lead disks by measuring variations of GSO magnetization with a dc-SQUID magnetometer. Such an induced magnetization can be interpreted as the effect of a long-range spin dependent interaction mediated by axions or Axion Like Particles (ALPs). The corresponding coupling strength is proportional to the C…
Search for galactic axions with a traveling wave parametric amplifier
INFN, Laboratori Nazionali di Legnaro（意大利国家核物理研究所，莱尼亚罗国家实验室）；INFN, Sezione di Padova（意大利国家核物理研究所，帕多瓦分部）；Dipartimento di Fisica e Astronomia（物理与天文学系）；Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel（格勒诺布尔阿尔卑斯大学，法国国家科学研究中心，格勒诺布尔理工学院，内耳研究所）；INFN, Laboratori Nazionali di Frascati（意大利国家核物理研究所，弗拉斯卡蒂国家实验室）
We report the first search results for axion dark matter using an 18\,T high-temperature superconducting magnet haloscope. The scan frequency ranges from 4.7789 to 4.8094\,GHz. No significant signal consistent with the Galactic halo dark matter axion is observed. The results set the best upper bound of axion-photon-photon coupling ($g_{aγγ}$) in the mass ranges of 19.764 to 19.771\,$μ$eV (19.863 to 19.890\,$μ$eV) at 1.5$\times|g_{aγγ}^{\text{KSVZ}}|$ (1.7$\times|g_{aγγ}^{\text{KSVZ}}|$), and 19.772 to 19.863\,$μ$eV at 2.7 $\times|g_{aγγ}^{\text{KSVZ}}|$ with 90\% confidence level, respectively…
This Letter reports results from a haloscope search for dark matter axions with masses between 2.66 and 2.81 $μ$eV. The search excludes the range of axion-photon couplings predicted by plausible models of the invisible axion. This unprecedented sensitivity is achieved by operating a large-volume haloscope at sub-kelvin temperatures, thereby reducing thermal noise as well as the excess noise from the ultra-low-noise SQUID amplifier used for the signal power readout. Ongoing searches will provide nearly definitive tests of the invisible axion model over a wide range of axion masses.
This paper reports on a cavity haloscope search for dark matter axions in the galactic halo in the mass range $2.81$-$3.31$ $μeV$. This search excludes the full range of axion-photon coupling values predicted in benchmark models of the invisible axion that solve the strong CP problem of quantum chromodynamics, and marks the first time a haloscope search has been able to search for axions at mode crossings using an alternate cavity configuration. Unprecedented sensitivity in this higher mass range is achieved by deploying an ultra low-noise Josephson parametric amplifier as the first stage sign…
Among solutions of the strong CP problem, the "invisible" axion in the narrow axion window is argued to be the remaining possibility among natural solutions on the smallness of $\barθ$. Related to the gravity spoil of global symmetries, some prospective invisible axions from theory point of view are discussed. In all these discussions, including the observational possibility, cosmological constraints must be included.
We present the first results of a search for invisible axion dark matter using a multiple-cell cavity haloscope. This cavity concept was proposed to provide a highly efficient approach to high mass regions compared to the conventional multiple-cavity design, with larger detection volume, simpler detector setup, and unique phase-matching mechanism. Searches with a double-cell cavity superseded previous reports for the axion-photon coupling over the mass range between 13.0 and 13.9$\,μ$eV. This result not only demonstrates the novelty of the cavity concept for high-mass axion searches, but also …
We report the results from a haloscope search for axion dark matter in the $3.3\text{-}4.2~μ$eV mass range. This search excludes the axion-photon coupling predicted by one of the benchmark models of "invisible" axion dark matter, the KSVZ model. This sensitivity is achieved using a large-volume cavity, a superconducting magnet, an ultra low noise Josephson parametric amplifier, and sub-Kelvin temperatures. The validity of our detection procedure is ensured by injecting and detecting blind synthetic axion signals.
The origin of `invisible' axion in four dimensional effective beyond-standard models from string compactification is discussed and its refined passover through the QCD phase transition is presented toward a reliable estimate of the current axion energy density in terms of the initial misalignment angle $\barθ_1$. The explicit examples are presented in a flipped SU(5) GUT model. This allows to introduce a flavor symmetry through string compactification, and hence we also comment on the source of flavor symmetries from string compactification and attempts to fit the resulting Yukawa couplings to…
Search for post-inflationary QCD axions with a quantum-limited tunable microwave receiver
INFN, Sezione di Padova（意大利国家核物理研究所帕多瓦分部）；Dipartimento di Fisica e Astronomia, Padova（帕多瓦大学物理与天文学系）；INFN, Laboratori Nazionali di Frascati（意大利国家核物理研究所弗拉斯卡蒂国家实验室）；Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel（格勒诺布尔阿尔卑斯大学）；INFN, Sezione di Napoli（意大利国家核物理研究所那不勒斯分部）；INFN, Laboratori Nazionali di Legnaro（意大利国家核物理研究所莱尼亚罗国家实验室）；CNR-SPIN Complesso di Monte S. Angelo（国家研究委员会自旋物理中心蒙特山综合体）；Istituto di Fotonica e Nanotecnologie, CNR Fondazione Bruno Kessler（光子学与纳米技术研究所）；INFN, TIFPA（意大利国家核物理研究所 Trento 理论物理与应用物理部门）
The Center for Axion and Precision Physics Research (CAPP) was founded in 2013, with the ambition of shedding light on the strong CP problem and the proposed existence of axions. Much of CAPP's effort focuses on the direct detection of dark matter candidate axions with a series of local haloscope experiments, which endeavour to expand dramatically the coverage on the "invisible axion" mass range. The first two of them plan experimental runs during this year, tapping into ultra-low cryogenics and toroidal cavity geometries. The overall programme builds on cutting-edge technology, including deve…
Axion-like particles (ALPs) can provide a portal to new states of a dark sector. We study the phenomenology of this portal when the ALP mainly decays invisibly, while its interaction with the standard model sector proceeds essentially via its coupling to electrons and/or photons. We re-analyse existing limits from various collider and beam dump experiments, including in particular ALP production via electron/positron interactions, in addition to the usual production through ALP-photon coupling. We further discuss the interplay between these limits and the intriguing possibility of explaining s…
The invisible axion is a well-motivated hypothetical particle which could address two fundamental questions in modern physics - the CP symmetry problem in the strong interactions and the dark matter mystery of our universe. The plausible mass (frequency) range of the QCD axion as a dark matter candidate spans from ueV to meV (O(GHz) to O(THz)). The axion haloscope using a resonant cavity has provided the most sensitive search method in the microwave region. However, experimental searches have been limited to relatively low mass regions mainly due to the reduced cavity volume at high masses. As…
Light pseudoscalars interacting pre-dominantly with Standard Model gauge bosons (so-called axion-like particles or ALPs) occur frequently in extensions of the Standard Model. In this work we review and update existing constraints on ALPs in the keV to GeV mass region from colliders, beam dump experiments and astrophysics. We furthermore provide a detailed calculation of the expected sensitivity of Belle II, which can search for visibly and invisibly decaying ALPs, as well as long-lived ALPs. The Belle II sensitivity is found to be substantially better than previously estimated, covering wide r…
We explore a model based on the classically-scale invariant standard model (SM) with a strongly coupled vector-like dynamics, which is called hypercolor (HC). The scale symmetry is dynamically broken by the vector-like condensation at the TeV scale, so that the SM Higgs acquires the negative mass-squared by the bosonic seesaw mechanism to realize the electroweak symmetry breaking. An elementary pseudoscalar $S$ is introduced to give masses for the composite Nambu-Goldstone bosons (HC pions): the HC pion can be a good target to explore through a diphoton channel at the LHC. As the consequence o…
The cavity haloscope has been employed to detect microwave photons resonantly converted from invisible cosmic axions under a strong magnetic field. In this scheme, the axion-photon conversion power has been formulated to be valid for certain conditions, either $Q_{cavity}\ll Q_{\rm axion}$ or $Q_{cavity} \gg Q_{axion}$. This remedy, however, fails when these two quantities are comparable to each other. Furthermore, the noise power flow has been treated independently of the impedance mismatch of the system, which could give rise to misleading estimates of the experimental sensitivity. We revisi…
In this note we report on the development plans and first results of the Grenoble Axion Haloscope (GrAHal) project. It is aimed at developing a haloscope platform dedicated to the search for axion dark matter particles. We discuss its general framework and the plans to reach the sensitivity required to probe well known invisible axion models, over particularly relevant axion masses and coupling regions. We also present our first haloscope prototype and the result of its test run at liquid He temperature, setting a new exclusion limit $g_{a γγ} \leq 2.2 \times 10^{-13}~ \text{GeV}^{-1}$ ($g_{a …
The NA62 experiment at the CERN SPS reports a study of a sample of $4 \times10^{9}$ tagged $π^0$ mesons from $K^+ \to π^+ π^0 (γ)$, searching for the decay of the $π^0$ to invisible particles. No signal is observed in excess of the expected background fluctuations. An upper limit of $4.4 \times10^{-9}$ is set on the branching ratio at 90% confidence level, improving on previous results by a factor of 60. This result can also be interpreted as a model-independent upper limit on the branching ratio for the decay $K^+ \to π^+ X$, where $X$ is a particle escaping detection with mass in the range 0…
The QCD axion is one of the most compelling solutions of the strong CP problem. There are major current efforts into searching for an ultralight, invisible axion, which is believed to be the only phenomenologically viable realization of the QCD axion. Visible axions with decay constants at or below the electroweak scale are believed to have been long excluded by laboratory searches. Considering the significance of the axion solution of the strong CP problem, we revisit experimental constraints on QCD axions in the O(10 MeV) mass window. In particular, we find a variant axion model that remains…
A search of axions produced in nuclear transitions was performed at the Kuo-Sheng Nuclear Power Station with a high-purity germanium detector of mass 1.06 kg at a distance of 28 m from the 2.9 GW reactor core. The expected experimental signatures were mono-energetic lines produced by their Primakoff or Compton conversions at the detector. Based on 459.0/96.3 days of Reactor ON/OFF data, no evidence of axion emissions were observed and constraints on the couplings $\gagg$ and $\gaee$ versus axion mass $m_a$ within the framework of invisible axion models were placed. The KSVZ and DFSZ models can…
We study the decay of the $Z$ vector boson into a photon and a massless (invisible) dark photon in high-energy collisions. The photon can be used as trigger for the event, while the dark photon is detected indirectly as missing momentum in the event final state. We investigate the possibility of searching for such a dark photon at the LHC, HL-LHC and future lepton colliders, and compare the respective sensitivities. As expected, the best result is found for the lepton colliders running at the $Z$ mass, FCC-ee and CEPC, with a final sensitivity to branching ratios of order $O(10^{-11})$. We als…
If a supernova explosion occurs within a few hundred parsecs from the Earth, a huge number of axions, in addition to neutrinos, may arrive at the Earth. In this paper, we discuss in detail the prospect of detecting those supernova axions by an axion helioscope. With the help of a pre-supernova neutrino alert system, it is possible to point a helioscope at an exploding supernova in advance. The supernova axions can then be detected by a gamma-ray detector installed at the end of the helioscope. We call such a detection system an axion supernova-scope (SNscope). We propose a conceptual design fo…
The proposed LDMX experiment would provide roughly a meter-long region of instrumented tracking and calorimetry that acts as a beam stop for multi-GeV electrons in which each electron is tagged and its evolution measured. This would offer an unprecedented opportunity to access both collider-invisible and ultra-short lifetime decays of new particles produced in electron (or muon)-nuclear fixed-target collisions. In this paper, we show that the missing momentum channel and displaced decay signals in such an experiment could provide world-leading sensitivity to sub-GeV dark matter, millicharged p…
The results of a search for solar axions from the Korea Invisible Mass Search (KIMS) experiment at the Yangyang Underground Laboratory are presented. Low-energy electron-recoil events would be produced by conversion of solar axions into electrons via the axio-electric effect in CsI(Tl) crystals. Using data from an exposure of 34,596 $\rm kg \cdot days$, we set a 90 \% confidence level upper limit on the axion-electron coupling, $g_{ae}$, of $1.39 \times 10^{-11}$ for an axion mass less than 1 keV/$\rm c^2$. This limit is lower than the indirect solar neutrino bound, and fully excludes QCD axio…
New particles $ϕ$ in the MeV-GeV range produced at colliders and escaping detection can be searched for at operating $b-$ and $τ-$factories such as Belle II. A typical search topology involves pair-produced $τ$s (or mesons), one of which decaying to visibles plus the $ϕ$, and the other providing a tag. One crucial impediment of these searches is the limited ability to reconstruct the parents' separate boosts. This is the case in the 'typical' topology where both decay branches include escaping particles. We observe that such topology lends itself to the use of kinematic variables such as $M_2$…
Expected Sensitivity of the Light Dark Matter eXperiment to Long-Lived Dark Photons and Axion-Like Particles
Lund University（隆德大学）；University of Michigan（密歇根大学）；Stanford University（斯坦福大学）；University of California, Santa Barbara（加州大学圣塔芭芭拉分校）；University of Virginia（弗吉尼亚大学）；California Institute of Technology（加州理工学院）；Carnegie Mellon University（卡内基梅隆大学）；University of Minnesota（明尼苏达大学）；SLAC National Accelerator Laboratory（斯坦福直线加速器中心）
We study exotic Higgs decays $h \to Z X$, with $X$ an invisible beyond the Standard Model (SM) particle, resulting in a semi-dark final state. Such exotic Higgs decays may occur in theories of axion-like-particles (ALPs), dark photons or pseudoscalar mediators between the SM and dark matter. The SM process $h\to Zν\barν$ represents an irreducible "neutrino floor" background to these new physics searches, providing also a target experimental sensitivity for them. We analyze $h \to Z + \text{invisible}$ searches at the LHC and a future ILC, showing that these exotic Higgs decays can yield sensit…
We propose a novel way to search for the dark photon ($A'$), the axion-like pseudo-scalar ($a$), the dark scalar ($ϕ$), and the light dark matter ($χ$) in the Compton-like processes, $γ+ e^- \rightarrow A'/a/ϕ+ e^-$ with $A'/a/ϕ$ decaying into leptons, photons, or $χ$'s (when permitted) for the mass ranges of $m_{A'/a/ϕ} \leq$ 100 MeV/$c^2$ and $m_χ \leq $ 50 MeV/$c^2$. We examine how the past, current, and future fixed target experiments can use this under-explored production mechanism of dark particles. We show that the existing and planned tagged photon beam fixed-target experiments (GlueX,…
The nature of dark matter, the invisible substance making up over $80\%$ of the matter in the Universe, is one of the most fundamental mysteries of modern physics. Ultralight bosons such as axions, axion-like particles or dark photons could make up most of the dark matter. Couplings between such bosons and nuclear spins may enable their direct detection via nuclear magnetic resonance (NMR) spectroscopy: as nuclear spins move through the galactic dark-matter halo, they couple to dark-matter and behave as if they were in an oscillating magnetic field, generating a dark-matter-driven NMR signal. …
The $B^+ \to K^+ ν\bar ν$ decay as a QCD axion search: comparing reinterpretation approaches
IPHC, Université de Strasbourg et CNRS（斯特拉斯堡大学）；LAPTh, Université Savoie Mont-Blanc et CNRS（萨瓦蒙布朗大学）；IJCLab, Pôle Théorie, et Université Paris-Saclay（巴黎萨克雷大学）
通过比较运动学变量空间的选择，解释 Belle II 数据中 B+→K+νν̄ 衰变对 QCD 轴子搜索的灵敏度差异，发现精细的 q²_rec 分箱能有效分辨窄信号，而 BDT 变量对轴子搜索区分能力有限，建议合作组同时发布物理变量空间的似然投影以提高可重解释性。
