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1. Characterization of mini-CryoCube detectors from the RICOCHET experiment commissioning at the Institut Laue-Langevin

   https://doi.org/10.1103/7xy6-jq3c  

   Armatol, A; Augier, C; Bailly-Salins, L; Baulieu, G; Bergé, L; Billard, J; Blé, J; Bres, G; Bret, J-L; Broniatowski, A; et al (December 2025, Physical Review D)

   The experiment aims to measure the coherent elastic neutrino-nucleus scattering process from antineutrinos emitted by a research nuclear reactor operated by the Institut Laue-Langevin (Grenoble, France). This article presents a description of the experimental installation and the detector performance achieved during its commissioning with a mini-CryoCube module consisting of three 42-g germanium cryogenic calorimeters. The baseline resolutions and background levels are reported both during reactor-on and reactor-off periods and as noise mitigation techniques were improved. A baseline resolution of 40 eV electron equivalent was achieved for the ionization channel after setup improvements, and the phonon channel resolutions ranged from 50 to 80 eV of total phonon energy. In the energy region from 2 to 7 keV, a nuclear recoil rate of $14\left(3\right)\mathrm{events}/\left(\mathrm{kg}\mathrm{day}\mathrm{keV}\right)$ is measured during the reactor-off period selecting events in coincidence with muon veto signals. This rate is in agreement with the cosmogenic neutron rate calculated from GEANT4 simulations. After the rejection of events in coincidence with signals in the muon veto detectors, a combined 90% confidence level limit on the nuclear recoil background of $<9\mathrm{events}/\left(\mathrm{kg}\mathrm{day}\mathrm{keV}\right)$ is obtained in that energy region during the reactor-on period, which is compatible with our GEANT4 model calculation corresponding to a total rate of $5\mathrm{events}/\left(\mathrm{kg}\mathrm{day}\mathrm{keV}\right)$ . The sensitivity of this analysis was however found to be limited by a surface event contamination which is currently being addressed by the Collaboration with upgraded detectors. 

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2. First Results on the Search for Lepton Number Violating Neutrinoless Double-β Decay with the LEGEND-200 Experiment

   https://doi.org/10.1103/25tk-nctn  

   Acharya, H; Ackermann, N; Agostini, M; Alexander, A; Andreoiu, C; Araujo, G R; Avignone, F T; Babicz, M; Bae, W; Bakalyarov, A M; et al (January 2026, Physical Review Letters)

   The LEGEND Collaboration is searching for neutrinoless double-beta ( $0\nu \beta \beta$ ) decay by operating high-purity germanium detectors enriched in ${}^{76}\mathrm{Ge}$ in a low-background liquid argon environment. Building on key technological innovations from the GERmanium Detector Array (GERDA) experiment and the MAJORANA DEMONSTRATOR experiment, LEGEND-200 has performed a first $0\nu \beta \beta$ decay search based on 61.0 kg yr of data. Over half of this exposure comes from our highest performing detectors, including newly developed inverted-coaxial detectors, and is characterized by an estimated background level of ${0.5}_{-0.2}^{+0.3}\mathrm{cts}/\left(\mathrm{keV}\mathrm{ton}\mathrm{yr}\right)$ in the $0\nu \beta \beta$ decay signal region. A combined analysis of data from GERDA, the MAJORANA DEMONSTRATOR, and LEGEND-200, characterized by a 90% confidence level exclusion sensitivity of $2.8\times {10}^{26}\mathrm{yr}$ on the half-life of $0\nu \beta \beta$ decay, reveals no evidence for a signal and sets a new observed lower limit at $T_{1/2}^{0\nu }>1.9\times {10}^{26}\mathrm{yr}$ (90% confidence level). Assuming the decay is mediated by Majorana neutrinos, this corresponds to an upper limit on the effective Majorana mass in the range $m_{\beta \beta }<75–200\mathrm{meV}$ , depending on the adopted nuclear matrix element. 

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3. Detecting gravitational signatures of dark matter with atom gradiometers

   https://doi.org/10.1103/xs7b-zgtj  

   Badurina, Leonardo; Du, Yufeng; Lee, Vincent_S H; Wang, Yikun; Zurek, Kathryn M (September 2025, Physical Review D)

   We study the purely gravitational signatures of dark matter from the ultralight to the ultraheavy mass range in proposed long-baseline atom gradiometers, focusing on terrestrial designs, such as AION-km and MAGIS-km, as well as space-based concepts, such as MAGIS-space, AEDGE and $\mathrm{AEDGE}+$ . Due to its exceptional acceleration sensitivity and depending on astrophysical backgrounds, a detector similar to $\mathrm{AEDGE}+$ could detect a dark matter subcomponent which constitutes $\mathcal{O}(10\%)$ of the local dark matter energy density and is populated by compact clumps of mass between ${10}^6\mathrm{kg}$ and ${10}^{10}\mathrm{kg}$ ( ${10}^{-25}{M}_{\odot }\lesssim M\lesssim {10}^{-21}{M}_{\odot }$ ) in an otherwise unexplored region of dark matter model space. Furthermore, because the gravitational observable depends on the relative gravitational time delay measured by spatially separated atomic clouds, we find that atom gradiometers are parametrically more sensitive than laser interferometers, such as LIGO and LISA, to fast-oscillating spacetime perturbations sourced by energy density and pressure fluctuations of ultralight dark matter. Depending on astrophysical backgrounds, a detector akin to $\mathrm{AEDGE}+$ could probe a DM overdensity of $\mathcal{O}\left(10\right)$ times the local dark matter energy density for masses $m\lesssim {10}^{-17}\mathrm{eV}$ . 

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4. Effective field theory and inelastic dark matter results from XENON1T

   https://doi.org/10.1103/PhysRevD.109.112017  

   Aprile, E; Abe, K; Agostini, F; Ahmed_Maouloud, S; Althueser, L; Andrieu, B; Angelino, E; Angevaare, J R; Antochi, V C; Antón_Martin, D; et al (June 2024, Physical Review D)

   In this work, we expand on the XENON1T nuclear recoil searches to study the individual signals of dark matter interactions from operators up to dimension eight in a chiral effective field theory (ChEFT) and a model of inelastic dark matter (iDM). We analyze data from two science runs of the XENON1T detector totaling $1\mathrm{t}\times \mathrm{yr}$ exposure. For these analyses, we extended the region of interest from $[4.9,40.9]{\mathrm{keV}}_{\mathrm{NR}}$ to $[4.9,54.4]{\mathrm{keV}}_{\mathrm{NR}}$ to enhance our sensitivity for signals that peak at nonzero energies. We show that the data are consistent with the background-only hypothesis, with a small background overfluctuation observed peaking between 20 and $50{\mathrm{keV}}_{\mathrm{NR}}$ , resulting in a maximum local discovery significance of $1.7\sigma$ for the $\mathrm{Vector}\otimes {\text{Vector}}_{\text{strange}}$ ChEFT channel for a dark matter particle of $70\mathrm{GeV}/c^2$ and $1.8\sigma$ for an iDM particle of $50\mathrm{GeV}/c^2$ with a mass splitting of $100\mathrm{keV}/c^2$ . For each model, we report 90% confidence level upper limits. We also report upper limits on three benchmark models of dark matter interaction using ChEFT where we investigate the effect of isospin-breaking interactions. We observe rate-driven cancellations in regions of the isospin-breaking couplings, leading to up to 6 orders of magnitude weaker upper limits with respect to the isospin-conserving case. Published by the American Physical Society2024 

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5. Search for nucleon decay via $p\to \nu {\pi }^{+}$ and $n\to \nu {\pi }^0$ in 0.484 Mton-year of Super-Kamiokande data

   https://doi.org/10.1103/gwc6-55bg  

   Jung, S; Abe, K; Asaoka, Y; Harada, M; Hayato, Y; Hiraide, K; Hung, T H; Ieki, K; Ikeda, M; Kameda, J; et al (January 2026, Physical Review D)

   We present the results of searches for nucleon decays via $p\to \nu {\pi }^{+}$ and $n\to \nu {\pi }^0$ using a $0.484\mathrm{Mt}·\mathrm{yr}$ exposure of Super-Kamiokande I-V data covering the entire pure water phase of the experiment. Various improvements on the previous 2014 nucleon decay search [], which used an exposure of $0.173\mathrm{Mt}·\mathrm{yr}$ , are incorporated. The physics models related to pion production and nuclear interaction are refined with external data, and a more comprehensive set of systematic uncertainties, now including those associated with the atmospheric neutrino flux and pion production channels, is considered. Also, the fiducial volume has been expanded by 21%. No significant indication of a nucleon decay signal is found beyond the expected background. Lower bounds on the nucleon partial lifetimes are determined to be $3.5\times {10}^{32}\mathrm{yr}$ for $p\to \nu {\pi }^{+}$ and $1.4\times {10}^{33}\mathrm{yr}$ for $n\to \nu {\pi }^0$ at 90% confidence level. 

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