More Like this

1. Search for Light Dark Matter in Low-Energy Ionization Signals from XENONnT

   https://doi.org/10.1103/PhysRevLett.134.161004  

   Aprile, E; Aalbers, J; Abe, K; Ahmed_Maouloud, S; Althueser, L; Andrieu, B; Angelino, E; Antón_Martin, D; Arneodo, F; Baudis, L; et al (April 2025, Physical Review Letters)

   We report on a blinded search for dark matter with single- and few-electron signals in the first science run of XENONnT relying on a novel detector response framework that is physics model dependent. We derive 90% confidence upper limits for dark matter-electron interactions. Heavy and light mediator cases are considered for the standard halo model and dark matter up-scattered in the Sun. We set stringent new limits on dark matter-electron scattering via a heavy mediator with a mass within $10–20\mathrm{MeV}/c^2$and electron absorption of axionlike particles and dark photons for $m_{\chi }$below $0.03\mathrm{keV}/c^2$. Published by the American Physical Society2025 

   more » « less
2. Constraints on metastable superheavy dark matter coupled to sterile neutrinos with the Pierre Auger Observatory

   https://doi.org/10.1103/PhysRevD.109.L081101  

   Abdul_Halim, A; Abreu, P; Aglietta, M; Allekotte, I; Almeida_Cheminant, K; Almela, A; Aloisio, R; Alvarez-Muñiz, J; Ammerman_Yebra, J; Anastasi, G A; et al (April 2024, Physical Review D)

   Dark matter particles could be superheavy, provided their lifetime is much longer than the age of the Universe. Using the sensitivity of the Pierre Auger Observatory to ultrahigh energy neutrinos and photons, we constrain a specific extension of the Standard Model of particle physics that meets the lifetime requirement for a superheavy particle by coupling it to a sector of ultralight sterile neutrinos. Our results show that, for a typical dark coupling constant of 0.1, the mixing angle ${\theta }_m$between active and sterile neutrinos must satisfy, roughly, ${\theta }_m\lesssim 1.5\times {10}^{-6}(M_X/{10}^9\mathrm{GeV}{)}^{-2}$for a mass $M_X$of the dark-matter particle between ${10}^8\mathrm{GeV}$and ${10}^{11}\mathrm{GeV}$. Published by the American Physical Society2024 

   more » « less
3. Dual-Baseline Search for Active-to-Sterile Neutrino Oscillations in NOvA

   https://doi.org/10.1103/PhysRevLett.134.081804  

   Acero, M A; Acharya, B; Adamson, P; Anfimov, N; Antoshkin, A; Arrieta-Diaz, E; Asquith, L; Aurisano, A; Back, A; Balashov, N; et al (February 2025, Physical Review Letters)

   We report a search for neutrino oscillations to sterile neutrinos under a model with three active and one sterile neutrinos ( $3+1$model). This analysis uses the NOvA detectors exposed to the NuMI beam, running in neutrino mode. The data exposure, $13.6\times {10}^{20}$protons on target, doubles that previously analyzed by NOvA, and the analysis is the first to use ${\nu }_{\mu }$charged-current interactions in conjunction with neutral-current interactions. Neutrino samples in the near and far detectors are fitted simultaneously, enabling the search to be carried out over a $\mathrm{\Delta }{m}_{41}^2$range extending 2 (3) orders of magnitude above (below) $1{\mathrm{eV}}^2$. NOvA finds no evidence for active-to-sterile neutrino oscillations under the $3+1$model at 90% confidence level. New limits are reported in multiple regions of parameter space, excluding some regions currently allowed by IceCube at 90% confidence level. We additionally set the most stringent limits for anomalous ${\nu }_{\tau }$appearance for $\mathrm{\Delta }{m}_{41}^2\le 3{\mathrm{eV}}^2$. Published by the American Physical Society2025 

   more » « less
4. First Search for Light Dark Matter in the Neutrino Fog with XENONnT

   https://doi.org/10.1103/PhysRevLett.134.111802  

   Aprile, E; Aalbers, J; Abe, K; Ahmed_Maouloud, S; Althueser, L; Andrieu, B; Angelino, E; Antón_Martin, D; Arneodo, F; Baudis, L; et al (March 2025, Physical Review Letters)

   We search for dark matter (DM) with a mass $[3,12]\mathrm{GeV}/c^2$using an exposure of $3.51\mathrm{tonne}\hspace{0.17em}\mathrm{year}$with the XENONnT experiment. We consider spin-independent DM-nucleon interactions mediated by a heavy or light mediator, spin-dependent DM-neutron interactions, momentum-dependent DM scattering, and mirror DM. Using a lowered energy threshold compared to the previous weakly interacting massive particle search, a blind analysis of [0.5, 5.0] keV nuclear recoil events reveals no significant signal excess over the background. XENONnT excludes spin-independent DM-nucleon cross sections $>2.5\times {10}^{-45}{\mathrm{cm}}^2$at 90% confidence level for $6\mathrm{GeV}/c^2$DM. In the considered mass range, the DM sensitivity approaches the “neutrino fog,” the limitation where neutrinos produce a signal that is indistinguishable from that of light DM-xenon nucleus scattering. Published by the American Physical Society2025 

   more » « less
5. Search for high-mass exclusive diphoton production with tagged protons in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$

   https://doi.org/10.1103/PhysRevD.110.012010  

   Tumasyan, A; Adam, W; Andrejkovic, J W; Bergauer, T; Chatterjee, S; Damanakis, K; Dragicevic, M; Escalante_Del_Valle, A; Hussain, P S; Jeitler, M; et al (July 2024, Physical Review D)

   A search is presented for high-mass exclusive diphoton production via photon-photon fusion in proton-proton collisions at $\sqrt{s}=13\mathrm{TeV}$in events where both protons survive the interaction. The analysis utilizes data corresponding to an integrated luminosity of $103{\mathrm{fb}}^{-1}$collected in 2016–2018 with the central CMS detector and the CMS and TOTEM precision proton spectrometer (PPS). Events that have two photons with high transverse momenta ( $p_{\mathrm{T}}^{\gamma }>100\mathrm{GeV}$), back-to-back in azimuth, and with a large diphoton invariant mass ( $m_{\gamma \gamma }>350\mathrm{GeV}$) are selected. To remove the dominant inclusive diphoton backgrounds, the kinematic properties of the protons detected in PPS are required to match those of the central diphoton system. Only events having opposite-side forward protons detected with a fractional momentum loss between 0.035 and 0.15 (0.18) for the detectors on the negative (positive) side of CMS are considered. One exclusive diphoton candidate is observed for an expected background of 1.1 events. Limits at 95% confidence level are derived for the four-photon anomalous coupling parameters $\left|{\zeta }_1\right|<0.073{\mathrm{TeV}}^{-4}$and $\left|{\zeta }_2\right|<0.15{\mathrm{TeV}}^{-4}$, using an effective field theory. Additionally, upper limits are placed on the production of axionlike particles with coupling strength to photons $f^{-1}$that varies from $0.03{\mathrm{TeV}}^{-1}$to $1{\mathrm{TeV}}^{-1}$over the mass range from 500 to 2000 GeV. © 2024 CERN, for the CMS and TOTEMs Collaboration2024CERN 

   more » « less