This Letter reports the first direct observation of muon antineutrino disappearance. The MINOS experiment has taken data with an accelerator beam optimized for ν(μ) production, accumulating an ...exposure of 1.71 × 10²⁰ protons on target. In the Far Detector, 97 charged current ν(μ) events are observed. The no-oscillation hypothesis predicts 156 events and is excluded at 6.3σ. The best fit to oscillation yields |Δm²| = 3.36(-0.40)(+0.46)(stat) ± 0.06(syst) × 10⁻³ eV², sin²(2θ) = 0.86(-0.12)(+0.11)(stat) ± 0.01(syst). The MINOS ν(μ) and ν(μ) measurements are consistent at the 2.0% confidence level, assuming identical underlying oscillation parameters.
A cobalt complex supported by the 2-(diisopropylphosphaneyl)benzenethiol ligand was synthesized and its electronic structure and reactivity were explored.
We report new constraints on flavor-changing nonstandard neutrino interactions from the MINOS long-baseline experiment using νe and ν¯e appearance candidate events from predominantly νμ and ν¯μ ...beams. We used a statistical selection algorithm to separate νe candidates from background events, enabling an analysis of the combined MINOS neutrino and antineutrino data. We observe no deviations from standard neutrino mixing, and thus place constraints on the nonstandard interaction matter effect, |ϵeτ|, and phase, (δCP+δeτ), using a 30-bin likelihood fit.
Co(bds)
2
n
Bu
4
N (where bds = 1,2-benzenediselenolate) was identified as an electrocatalyst for the hydrogen evolution reaction. Mechanistic studies indicated that a black precipitate, which ...formed upon treating Co(bds)
2
−
with acid, as well as the one-electron reduced species, Co(bds)
2
2−
, were viable catalytic intermediates. We propose two kinetically-competent pathways for H
2
evolution: EC and CE (E = electrochemical, C = chemical step).
Co(bds)
2
n
Bu
4
N (where bds = 1,2-benzenediselenolate) was identified as an electrocatalyst for H
2
evolution. Mechanistic studies indicate that with acid a protonated oligomeric {Co(bds)
2
(H)
x
x
−1
}
m
is formed, which was found to reenter the catalytic cycle and generate H
2
.
The reduction of CO
2
into higher energy products such as carbon-based fuels and feedstocks is an attractive strategy for mitigating the continuous rise in CO
2
emissions associated with the growing ...global energy demand. Rhenium tricarbonyl complexes bearing 2,2′-bipyridine (2,2′-bpy) ligands are well-established molecular electrocatalysts for the selective reduction of CO
2
to CO. Construction of efficient devices for this electrochemical process requires the immobilization of electrocatalysts to electrode surfaces. To integrate Re(2,2′-bpy)(CO)
3
fragments into a covalent organic framework (COF), Re(5,5′-diamine-2,2′-bpy)(CO)
3
Cl (
1
) was synthesized and electrochemically investigated. Complex
1
is an active and selective electrocatalyst for the reduction of CO
2
to CO with excellent faradaic efficiency (99%). The presence of the amine substituents leads to a destabilization of the π* orbital of the 5,5′-diamine-2,2′-bpy ligand with respect to the metal center. Therefore,
1
requires more negative potentials (−2.47 V
vs.
Fc
+/0
) to reach the doubly reduced catalytically active species. DFT studies were conducted to understand the electronic structure of
1
, and support the destabilizing effect of the amine substituents. The Re-2,2′-bpy fragments were successfully integrated into a COF containing 2,2′-bpy moieties (COF-2,2′-bpy)
via
a post-metallation synthetic route to generate COF-2,2′-bpy-Re. A composite of COF-2,2′-bpy-Re, carbon black, and polyvinylidene fluoride (PVDF) was readily immobilized onto glassy carbon electrodes and electrocatalytic CO
2
reduction to CO was observed at −2.8 V
vs.
Fc
0/+
, with a faradaic efficiency of 81% for CO production.
The reduction of CO
2
into higher energy products such as carbon-based fuels and feedstocks is an attractive strategy for mitigating the continuous rise in CO
2
emissions associated with the growing global energy demand.
The charge ratio, R sub(mu)=N sub(mu+)/N sub(mu-), for cosmogenic multiple-muon events observed at an underground depth of 2070 mwe has been measured using the magnetized MINOS Far Detector. The ...multiple-muon events, recorded nearly continuously from August 2003 until April 2012, comprise two independent data sets imaged with opposite magnetic field polarities, the comparison of which allows the systematic uncertainties of the measurement to be minimized. The multiple-muon charge ratio is determined to be (ProQuest: Formulae and/or non-USASCII text omitted). This measurement complements previous determinations of single-muon and multiple-muon charge ratios at underground sites and serves to constrain models of cosmic-ray interactions at TeV energies.
The reduction of CO2into higher energy products such as carbon-based fuels and feedstocks is an attractive strategy for mitigating the continuous rise in CO2emissions associated with the growing ...global energy demand.
The NuMI neutrino beam Andrews, M.; Anghel, I.; Barish, B. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2015, Letnik:
806, Številka:
C
Journal Article
Recenzirano
Odprti dostop
Our paper describes the hardware and operations of the Neutrinos at the Main Injector (NuMI) beam at Fermilab. It elaborates on the design considerations for the beam as a whole and for individual ...elements. The most important part of our design details pertaining to individual components is described. Beam monitoring systems and procedures, including the tuning and alignment of the beam and NuMI long-term performance, are also discussed.
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