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1. Hunting nonstandard neutrino interactions and leptoquarks in dark matter experiments

   https://doi.org/10.1088/1475-7516/2024/11/068  

   Schwemberger, Thomas; Takhistov, Volodymyr; Yu, Tien-Tien (November 2024, Journal of Cosmology and Astroparticle Physics)

   Abstract Next generation direct dark matter (DM) detection experiments will have unprecedented capabilities to explore coherent neutrino-nucleus scattering (CEνNS) complementary to dedicated neutrino experiments. We demonstrate that future DM experiments can effectively probe nonstandard neutrino interactions (NSI) mediated by scalar fields in the scattering of solar and atmospheric neutrinos. We set first limits onS¹leptoquark models that result in sizableμ-dandτ-dsector neutrino NSI CEνNS contributions using LUX-ZEPLIN (LZ) data. As we show, near future DM experiments reaching ∼𝒪(100) ton-year exposure, such as argon-based ARGO and xenon-based DARWIN, can probe parameter space of leptoquarks beyond the reach of current and planned collider facilities. We also analyze for the first time prospects for testing NSI in lead-based detectors. We discuss the ability of leptoquarks in the parameter space of interest to also explain the neutrino masses and (g-2)_μobservations. 

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2. Measurement of the axial vector form factor from antineutrino–proton scattering

   https://doi.org/10.1038/s41586-022-05478-3  

   Cai, T.; Moore, M. L.; Olivier, A.; Akhter, S.; Dar, Z. Ahmad; Ansari, V.; Ascencio, M. V.; Bashyal, A.; Bercellie, A.; Betancourt, M.; et al (February 2023, Nature)

   Abstract Scattering of high energy particles from nucleons probes their structure, as was done in the experiments that established the non-zero size of the proton using electron beams 1 . The use of charged leptons as scattering probes enables measuring the distribution of electric charges, which is encoded in the vector form factors of the nucleon 2 . Scattering weakly interacting neutrinos gives the opportunity to measure both vector and axial vector form factors of the nucleon, providing an additional, complementary probe of their structure. The nucleon transition axial form factor, F A , can be measured from neutrino scattering from free nucleons, ν μ n  →  μ − p and $${\bar{\nu }}_{\mu }p\to {\mu }^{+}n$$ ν ¯ μ p → μ + n , as a function of the negative four-momentum transfer squared ( Q 2 ). Up to now, F A ( Q 2 ) has been extracted from the bound nucleons in neutrino–deuterium scattering 3–9 , which requires uncertain nuclear corrections 10 . Here we report the first high-statistics measurement, to our knowledge, of the $${\bar{\nu }}_{\mu }\,p\to {\mu }^{+}n$$ ν ¯ μ p → μ + n cross-section from the hydrogen atom, using the plastic scintillator target of the MINERvA 11 experiment, extracting F A from free proton targets and measuring the nucleon axial charge radius, r A , to be 0.73 ± 0.17 fm. The antineutrino–hydrogen scattering presented here can access the axial form factor without the need for nuclear theory corrections, and enables direct comparisons with the increasingly precise lattice quantum chromodynamics computations 12–15 . Finally, the tools developed for this analysis and the result presented are substantial advancements in our capabilities to understand the nucleon structure in the weak sector, and also help the current and future neutrino oscillation experiments 16–20 to better constrain neutrino interaction models. 

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3. Search for charged lepton flavor violating decays of ϒ (1S)

   https://doi.org/10.1007/JHEP05(2022)095  

   Patra, S.; Bhardwaj, V.; Trabelsi, K.; Adachi, I.; Aihara, H.; Al Said, S.; Asner, D. M.; Atmacan, H.; Aushev, T.; Ayad, R.; et al (May 2022, Journal of High Energy Physics)

   A bstract We present a search for the charged lepton-flavor-violating decays ϒ(1 S ) → ℓ ± ℓ ′ ∓ and radiative charged lepton-flavour-violating decays ϒ(1 S ) → γ ℓ ± ℓ ′ ∓ [ ℓ , ℓ ′ = e, μ, τ ] using the 158 million ϒ(2 S ) sample collected by the Belle detector at the KEKB collider. This search uses ϒ(1 S ) mesons produced in ϒ(2 S ) → π + π − ϒ(1 S ) transitions. We do not find any significant signal, so we provide upper limits on the branching fractions at the 90% confidence level. 

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4. Measurement of $d^2\sigma /d\left|\overrightarrow{q}\right|d{E}_{\text{avail}}$ in charged current ${\nu }_{\mu }$ -nucleus interactions at $⟨E_{\nu }⟩=1.86\mathrm{GeV}$ using the NOvA Near Detector

   https://doi.org/10.1103/PhysRevD.111.052009  

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

   Double- and single-differential cross sections for inclusive charged-current ${\nu }_{\mu }$-nucleus scattering are reported for the kinematic domain 0 to $2\mathrm{GeV}/c$in three-momentum transfer and 0 to 2 GeV in available energy, at a mean ${\nu }_{\mu }$energy of 1.86 GeV. The measurements are based on an estimated 995,760 ${\nu }_{\mu }$charged-current (CC) interactions in the scintillator medium of the NOvA Near Detector. The subdomain populated by 2-particle-2-hole (2p2h) reactions is identified by the cross section excess relative to predictions for ${\nu }_{\mu }$-nucleus scattering that are constrained by a data control sample. Models for 2-particle-2-hole processes are rated by ${\chi }^2$comparisons of the predicted-versus-measured ${\nu }_{\mu }$CC inclusive cross section over the full phase space and in the restricted subdomain. Shortfalls are observed in neutrino generator predictions obtained using the theory-based València and SuSAv2 2p2h models. Published by the American Physical Society2025 

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5. Search for squarks and gluinos in final states with one isolated lepton, jets, and missing transverse momentum at $$\sqrt{s}=13$$  with the ATLAS detector

   https://doi.org/10.1140/epjc/s10052-021-09344-w  

   Aad, G.; Abbott, B.; Abbott, D. C.; Abed Abud, A.; Abeling, K.; Abhayasinghe, D. K.; Abidi, S. H.; AbouZeid, O. S.; Abraham, N. L.; Abramowicz, H.; et al (July 2021, The European Physical Journal C)

   null (Ed.)

   Abstract The results of a search for gluino and squark pair production with the pairs decaying via the lightest charginos into a final state consisting of two W bosons, the lightest neutralinos ( $$\tilde{\chi }^0_1$$ χ ~ 1 0 ), and quarks, are presented: the signal is characterised by the presence of a single charged lepton ( $$e^{\pm }$$ e ± or $$\mu ^{\pm }$$ μ ± ) from a W boson decay, jets, and missing transverse momentum. The analysis is performed using 139 fb $$^{-1}$$ - 1 of proton–proton collision data taken at a centre-of-mass energy $$\sqrt{s}=13$$ s = 13   delivered by the Large Hadron Collider and recorded by the ATLAS experiment. No statistically significant excess of events above the Standard Model expectation is found. Limits are set on the direct production of squarks and gluinos in simplified models. Masses of gluino (squark) up to 2.2  (1.4 ) are excluded at 95% confidence level for a light $$\tilde{\chi }^0_1$$ χ ~ 1 0 . 

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