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Creators/Authors contains: "Singh, V"

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  1. Misinformation in online spaces can stoke mistrust of established media, misinform the public and lead to radicalization. Hence, multiple automated algorithms for misinformation detection have been proposed in the recent past. However, the fairness (e.g., performance across left- and right- leaning news articles) of these algorithms has been repeatedly questioned, leading to decreased trust in such systems. This work motivates and grounds the need for an audit of machine learning based misinformation detection algorithms and possible ways to mitigate bias (if found). Using a large (N>100K) corpus of news articles, we report that multiple standard machine learning based misinformation detection approaches are susceptible to bias. Further, we find that an intuitive post-processing approach (Reject Option Classifier) can reduce bias while maintaining high accuracy in the above setting. The results pave the way for accurate yet fair misinformation detection algorithms. 
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  2. Abstract CUPID, the CUORE Upgrade with Particle Identification, is a next-generation experiment to search for neutrinoless double beta decay ($$0\mathrm {\nu \beta \beta }$$ 0 ν β β ) and other rare events using enriched Li$$_{2}$$ 2 $$^{100}$$ 100 MoO$$_{4}$$ 4 scintillating bolometers. It will be hosted by the CUORE cryostat located at the Laboratori Nazionali del Gran Sasso in Italy. The main physics goal of CUPID is to search for$$0\mathrm {\nu \beta \beta }$$ 0 ν β β of$$^{100}$$ 100 Mo with a discovery sensitivity covering the full neutrino mass regime in the inverted ordering scenario, as well as the portion of the normal ordering regime with lightest neutrino mass larger than 10 meV. With a conservative background index of 10$$^{-4}$$ - 4  cts$$/($$ / ( keV$$\cdot $$ · kg$$\cdot $$ · yr$$)$$ ) , 240 kg isotope mass, 5 keV FWHM energy resolution at 3 MeV and 10 live-years of data taking, CUPID will have a 90% C.L. half-life exclusion sensitivity of$$1.8\cdot 10^{27}$$ 1.8 · 10 27  yr, corresponding to an effective Majorana neutrino mass ($$m_{\beta \beta }$$ m β β ) sensitivity of 9–15 meV, and a$$3\sigma $$ 3 σ discovery sensitivity of$$1\cdot 10^{27}$$ 1 · 10 27  yr, corresponding to an$$m_{\beta \beta }$$ m β β range of 12–21 meV. 
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    Free, publicly-accessible full text available July 1, 2026
  3. The Cryogenic Underground Observatory for Rare Events (CUORE) is a detector array comprised by 988 5 cm × 5 cm × 5 cm TeO 2 crystals held below 20 mK, primarily searching for neutrinoless double-beta decay in Te 130 . Unprecedented in size among cryogenic calorimetric experiments, CUORE provides a promising setting for the study of exotic throughgoing particles. Using the first tonne year of CUORE’s exposure, we perform a search for hypothesized (FCPs), which are well-motivated by various standard model extensions and would have suppressed interactions with matter. Across the searched range of charges e / 24 e / 2 no excess of FCP candidate tracks is observed over background, setting leading limits on the underground FCP flux with charges e / 24 e / 5 at 90% confidence level. Using the low background environment and segmented geometry of CUORE, we establish the sensitivity of tonne-scale subkelvin detectors to diverse signatures of new physics. Published by the American Physical Society2024 
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    Free, publicly-accessible full text available December 1, 2025
  4. Double- and single-differential cross sections for inclusive charged-current ν μ -nucleus scattering are reported for the kinematic domain 0 to 2 GeV / c in three-momentum transfer and 0 to 2 GeV in available energy, at a mean ν μ energy of 1.86 GeV. The measurements are based on an estimated 995,760 ν μ 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 ν μ -nucleus scattering that are constrained by a data control sample. Models for 2-particle-2-hole processes are rated by χ 2 comparisons of the predicted-versus-measured ν μ 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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    Free, publicly-accessible full text available March 1, 2026
  5. 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 × 10 20 protons on target, doubles that previously analyzed by NOvA, and the analysis is the first to use ν μ 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 Δ m 41 2 range extending 2 (3) orders of magnitude above (below) 1 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 ν τ appearance for Δ m 41 2 3 eV 2 . Published by the American Physical Society2025 
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    Free, publicly-accessible full text available February 1, 2026
  6. Abstract Measuring observables to constrain models using maximum-likelihood estimation is fundamental to many physics experiments. Wilks' theorem provides a simple way to construct confidence intervals on model parameters, but it only applies under certain conditions. These conditions, such as nested hypotheses and unbounded parameters, are often violated in neutrino oscillation measurements and other experimental scenarios. Monte Carlo methods can address these issues, albeit at increased computational cost. In the presence of nuisance parameters, however, the best way to implement a Monte Carlo method is ambiguous. This paper documents the method selected by the NOvA experiment, the profile construction. It presents the toy studies that informed the choice of method, details of its implementation, and tests performed to validate it. It also includes some practical considerations which may be of use to others choosing to use the profile construction. 
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    Free, publicly-accessible full text available February 1, 2026
  7. This Letter reports a search for charge-parity ( C P ) symmetry violating nonstandard interactions (NSI) of neutrinos with matter using the NOvA Experiment, and examines their effects on the determination of the standard oscillation parameters. Data from ν μ ( ν ¯ μ ) ν μ ( ν ¯ μ ) and ν μ ( ν ¯ μ ) ν e ( ν ¯ e ) oscillation channels are used to measure the effect of the NSI parameters ϵ e μ and ϵ e τ . With 90% CL the magnitudes of the NSI couplings are constrained to be | ϵ e μ | 0.3 and | ϵ e τ | 0.4 . A degeneracy at | ϵ e τ | 1.8 is reported, and we observe that the presence of NSI limits sensitivity to the standard C P phase δ C P . Published by the American Physical Society2024 
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