This Letter reports a search for charge-parity (CP) 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[over ¯]_{μ})→ν_{μ}(ν[over ¯]_{μ}) and ν_{μ}(ν[over ¯]_{μ})→ν_{e}(ν[over ¯]_{e}) oscillation channels are used to measure the effect of the NSI parameters ϵ_{eμ} and ϵ_{eτ}. With 90% CL the magnitudes of the NSI couplings are constrained to be |ϵ_{eμ}|≲0.
View Article and Find Full Text PDFMono-β-diketonate compounds have been fleetingly observed in base metal catalyzed reactions, which are of current interest as alternatives to precious metal catalyzed reactions. Their isolation has been challenging due to synthetic and structural limitations of acac-type ligands, leading to the development of a related NacNac ligand platform. Herein we report the synthesis of a β-diketone capable of kinetically stabilizing relevant catalytic intermediates.
View Article and Find Full Text PDFThe inclusive electron neutrino charged-current cross section is measured in the NOvA near detector using 8.02×10^{20} protons-on-target in the NuMI beam. The sample of GeV electron neutrino interactions is the largest analyzed to date and is limited by ≃17% systematic rather than the ≃7.
View Article and Find Full Text PDFBy tailoring the coordination sphere of vanadium to accommodate a 7-coordinate geometry, a highly soluble (>1.3 M) and reducing (-1.2 V vs Ag/AgCl) flow battery electrolyte is generated from [V(DTPA)] (DTPA = diethylenetriaminepentaacetate).
View Article and Find Full Text PDFHigh-concentration operation of redox flow batteries (RFBs) is essential for increasing their energy-storage capacity, but non-acidic electrolytes struggle to achieve the high concentrations of metal ions dissolved in acid, limiting the development of energy-dense neutral pH electrolytes. We report neutral pH RFB operation of chromium 1,3-propylenediaminetetraacetate (CrPDTA) at concentrations of 1.2 M at room temperature and 1.
View Article and Find Full Text PDFEur Phys J C Part Fields
July 2022
DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6 6 6 m liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019-2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light.
View Article and Find Full Text PDFThe highly reducing Cr-(1,3-propylenediaminetetraacetate) (CrPDTA) complex (-1.1 V vs SHE) has been isolated from aqueous solution and the solid-state structure is described. The reduced CrPDTA complex is characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy, UV-vis spectroscopy, magnetic moment, and density functional theory calculations.
View Article and Find Full Text PDFThis Letter reports results from the first long-baseline search for sterile antineutrinos mixing in an accelerator-based antineutrino-dominated beam. The rate of neutral-current interactions in the two NOvA detectors, at distances of 1 and 810 km from the beam source, is analyzed using an exposure of 12.51×10^{20} protons-on-target from the NuMI beam at Fermilab running in antineutrino mode.
View Article and Find Full Text PDFEur Phys J C Part Fields
April 2021
The Deep Underground Neutrino Experiment (DUNE) will be a powerful tool for a variety of physics topics. The high-intensity proton beams provide a large neutrino flux, sampled by a near detector system consisting of a combination of capable precision detectors, and by the massive far detector system located deep underground. This configuration sets up DUNE as a machine for discovery, as it enables opportunities not only to perform precision neutrino measurements that may uncover deviations from the present three-flavor mixing paradigm, but also to discover new particles and unveil new interactions and symmetries beyond those predicted in the Standard Model (SM).
View Article and Find Full Text PDFThe synthesis, characterization, and photophysical properties of 4- and 6-coordinate Bi coordination complexes are reported. Bi(bzq) () and [Bi(bzq)]Br () (bzq = benzo[]quinoline) are synthesized by reaction of 9-Li-bzq with BiCl and BiBr, respectively. Absorption spectroscopy, electrochemistry, and DFT studies suggest that has 42% Bi 6s character in its highest-occupied molecular orbital (HOMO) as a result of six σ* interactions with the bzq ligands.
View Article and Find Full Text PDFHere, we outline some basic pitfalls in the electrochemical investigation of aqueous metal complexes and advocate for the use of bulk electrolysis in redox flow cells for electrolyte analysis. We demonstrate the methods of operation and performance of a lab scale redox flow battery (RFB), which is assembled from unmodified, commercially available material and cycled with a vanadium electrolyte in order to provide a comparative baseline of expected performance. Common misconceptions about the thermodynamic window for water splitting are addressed and further express the need to develop next-generation aqueous redox flow battery electrolytes.
View Article and Find Full Text PDFWe report the final measurement of the neutrino oscillation parameters Δm_{32}^{2} and sin^{2}θ_{23} using all data from the MINOS and MINOS+ experiments. These data were collected using a total exposure of 23.76×10^{20} protons on target producing ν_{μ} and ν[over ¯]_{μ} beams and 60.
View Article and Find Full Text PDFSearches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on the θ_{μe} mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Δm_{41}^{2}, excluding the 90% C.
View Article and Find Full Text PDFThe synthesis and characterization of a series of copper bis(β-diketonate) complexes, functionalized with sterically hindered -biphenyl and -terphenyl functional groups, are reported. X-ray structural analysis reveals that the ligands exhibit several modes of flexibility in order to accommodate the steric demand. Increased steric bulk of the ligands influences the Cu electrochemical reduction, which is likely due to inhibited ligand rotation.
View Article and Find Full Text PDFThe NOvA experiment has seen a 4.4σ signal of ν[over ¯]_{e} appearance in a 2 GeV ν[over ¯]_{μ} beam at a distance of 810 km. Using 12.
View Article and Find Full Text PDFMetal coordination complexes of the sterically hindered β-diketonate, 2,6-dimesitylbenzoyl pinacolone (esac), are reported for Co, Ni, Cu, and Zn. All four form ML2-type complexes with typical coordination behavior for late-metal β-diketonates, however the effects on established electrochemistry and reactivity vary somewhat per metal. For example, the striking chemical and electrochemical inertness of CoII(esac)2 to oxidation and disproportionation is atypical.
View Article and Find Full Text PDFBulky β-diketones have rarely exceeded dipivaloylmethane (DPM) in steric demand, largely due to synthetic limitations of the Claisen condensation. This work demonstrates hindered acid chlorides to be selective electrophiles in noncoordinating solvents for condensations with enolates. An improved synthesis of DPM is described (90% yield), and crowded β-diketones featuring bulky o-biphenyl or m-terphenyl fragments were prepared in good to excellent yields.
View Article and Find Full Text PDFA search for mixing between active neutrinos and light sterile neutrinos has been performed by looking for muon neutrino disappearance in two detectors at baselines of 1.04 and 735 km, using a combined MINOS and MINOS+ exposure of 16.36×10^{20} protons on target.
View Article and Find Full Text PDFThe synthesis of a sterically encumbered β-diketone ligand (acac) substituted with 2,6-(2,4,6-MeCH)CH is described. Coordination complexes of the type M(acac)Cl(solv) (M = Ti, V, Cr; solv = THF, CHCN) were prepared by the reaction of acac with MCl (M = V, Cr) or with TiCl to generate Ti(acac)Cl, followed by reduction. These complexes show a trend of alternating the cis/trans geometric preference with increasing d electron count (n = 0, 1, 2, 3), which is rationalized in part by the unusual ability of β-diketonates to behave as either a weak π donor or a π acceptor in the cis and trans geometries, respectively.
View Article and Find Full Text PDFThis Letter reports new results on muon neutrino disappearance from NOvA, using a 14 kton detector equivalent exposure of 6.05×10^{20} protons on target from the NuMI beam at the Fermi National Accelerator Laboratory. The measurement probes the muon-tau symmetry hypothesis that requires maximal θ_{23} mixing (θ_{23}=π/4).
View Article and Find Full Text PDFSearches for a light sterile neutrino have been performed independently by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to probe regions allowed by the Liquid Scintillator Neutrino Detector (LSND) and MiniBooNE experiments in a minimally extended four-neutrino flavor framework.
View Article and Find Full Text PDFWe report results of a search for oscillations involving a light sterile neutrino over distances of 1.04 and 735 km in a ν_{μ}-dominated beam with a peak energy of 3 GeV. The data, from an exposure of 10.
View Article and Find Full Text PDFWe report results from the first search for ν_{μ}→ν_{e} transitions by the NOvA experiment. In an exposure equivalent to 2.74×10^{20} protons on target in the upgraded NuMI beam at Fermilab, we observe 6 events in the Far Detector, compared to a background expectation of 0.
View Article and Find Full Text PDFStorage of photovoltaic and wind electricity in batteries could solve the mismatch problem between the intermittent supply of these renewable resources and variable demand. Flow batteries permit more economical long-duration discharge than solid-electrode batteries by using liquid electrolytes stored outside of the battery. We report an alkaline flow battery based on redox-active organic molecules that are composed entirely of Earth-abundant elements and are nontoxic, nonflammable, and safe for use in residential and commercial environments.
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