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Cronin-Hennessy, D.

Publications and source records attributed to Cronin-Hennessy, D..

At least 19 records

Measurement of neutrino-induced neutral-current coherent $π^0$ production in the NOvA near detector

The cross section of neutrino-induced neutral-current coherent $\pi^0$ production on a carbon-dominated target is measured in the NOvA near detector. This measurement uses a narrow-band neutrino beam with the average neutrino energy of 2.7\,GeV, xwhich is of interest to the ongoing and future long-baseline neutrino oscillation experiments. The measured, flux-averaged cross section is $\sigma = 14.0\pm0.9$\,(stat.)$\pm2.1$\,(syst.)$\times 10^{-40}$ $\text{cm}^2/$nucleus, consistent with model prediction. This result is the most precise measurement of neutral-current coherent $\pi^0$ production in the few-GeV neutrino energy region.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

New constraints on oscillation parameters from {nu}e appearance and {nu}{mu} disappearance in the NOvA experiment

We present updated results from the NOvA experiment for v(mu) -> v(mu) and v(mu) -> v(e) oscillations from an exposure of 8.85 x 10(20) protons on target, which represents an increase of 46% compared to our previous publication. The results utilize significant improvements in both the simulations and analysis of the data. A joint fit to the data for v(mu) disappearance and v(e) appearance gives the best-fit point as normal mass hierarchy, Delta m(32)(2) = 2.44 x 10(-3) eV(2)/c(4), sin(2) theta(23) = 0.56, and delta(CP) = 1.21 pi. The 68.3% confidence intervals in the normal mass hierarchy are Delta m(32)(2) is an element of[2.37, 2.52] x 10(-3) eV(2)/c(4) , sin(2) theta(23) is an element of [0.43; 0.51] boolean OR [0.52; 0.60], and delta(CP) is an element of [0, 0.21 pi] boolean OR [0.91 pi, 2 pi]. The inverted mass hierarchy is disfavored at the 95% confidence level for all choices of the other oscillation parameters.

Acero, M. A.↗

Search for active-sterile neutrino mixing using neutral-current interactions in NOvA

Here, we report results from the first search for sterile neutrinos mixing with active neutrinos through a reduction in the rate of neutral-current interactions over a baseline of 810 km between the NOvA detectors. Analyzing a 14-kton detector equivalent exposure of 6.05 × 10 20 protons-on-target in the NuMI beam at Fermilab, we observe 95 neutral-current candidates at the Far Detector compared with 83.5 ± 9.7(stat) ± 9.4(syst) events predicted assuming mixing only occurs between active neutrino species. No evidence for νμ→νs transitions is found. Interpreting these results within a 3+1 model, we place constraints on the mixing angles θ 24 < 20.8° and θ 34 < 31.2° at the 90% C.L. for 0.05 eV 2 ≤ Δm 41 2 ≤ 0.5 eV 2 , the range of mass splittings that produce no significant oscillations over the Near Detector baseline.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Determination of the number of ψ(3686) events at BESIII

The numbers of ψ(3686) events accumulated by the BESIII detector for the data taken during 2009 and 2012 are determined to be $(107.0\pm 0.8)\times {10}^{6}$ and $(341.1\pm 2.1)\times {10}^{6}$, respectively, by counting inclusive hadronic events, where the uncertainties are systematic and the statistical uncertainties are negligible. The number of events for the sample taken in 2009 is consistent with that of the previous measurement. The total number of ψ(3686) events for the two data taking periods is $(448.1\pm 2.9)\times {10}^{6}$.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Constraints on oscillation parameters from v e appearance and v μ disappearance in NOvA

Results are reported from an improved measurement of ν μ → ν e transitions by the NOvA experiment. Using an exposure equivalent to 6.05 × 10 20 protons on target, 33 νe candidates are observed with a background of 8.2 ± 0.8 (syst.). In this paper, combined with the latest NOvA νμ disappearance data and external constraints from reactor experiments on sin 2 2θ 13 , the hypothesis of inverted mass hierarchy with θ 23 in the lower octant is disfavored at greater than 93% C.L. for all values of δ CP .

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Measurement of the neutrino mixing angle θ 23 in NOvA

This Letter reports new results on muon neutrino disappearance from NOvA, using a 14 kton detector equivalent exposure of $6.05\times10^{20}$ protons-on-target from the NuMI beam at the Fermi National Accelerator Laboratory. The measurement probes the muon-tau symmetry hypothesis that requires maximal mixing ($\theta_{23} = \pi/4$). Assuming the normal mass hierarchy, we find $\Delta m^2 = (2.67 \pm 0.11)\times 10^{-3}$ eV$^2$ and $\sin^2 \theta_{23}$ at the two statistically degenerate values $0.404^{+0.030}_{-0.022}$ and $0.624^{+0.022}_{-0.030}$, both at the 68% confidence level. Finally, our data disfavor the maximal mixing scenario with 2.6 $\sigma$ significance.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Search for flavor-changing nonstandard neutrino interactions using $\nu_{e}$ appearance in MINOS

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.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Constraints on Large Extra Dimensions from the MINOS Experiment

We report new constraints on the size of large extra dimensions from data collected by the MINOS experiment between 2005 and 2012. Our analysis employs a model in which sterile neutrinos arise as Kaluza-Klein states in large extra dimensions and thus modify the neutrino oscillation probabilities due to mixing between active and sterile neutrino states. Using Fermilab’s Neutrinos at the Main Injector beam exposure of 10.56×1020 protons on target, we combine muon neutrino charged current and neutral current data sets from the Near and Far Detectors and observe no evidence for deviations from standard three-flavor neutrino oscillations. The ratios of reconstructed energy spectra in the two detectors constrain the size of large extra dimensions to be smaller than 0.45 μm at 90% C.L. in the limit of a vanishing lightest active neutrino mass. Stronger limits are obtained for nonvanishing masses.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Measurement of single $\pi^0$ production by coherent neutral-current $\nu$ Fe interactions in the MINOS Near Detector

Forward single π0 production by coherent neutral-current interactions, νA→νAπ0, is investigated using a 2.8×1020 protons-on-target exposure of the MINOS Near Detector. For single-shower topologies, the event distribution in production angle exhibits a clear excess above the estimated background at very forward angles for visible energy in the range 1–8 GeV. Cross sections are obtained for the detector medium comprised of 80% iron and 20% carbon nuclei with ⟨A⟩=48, the highest-⟨A⟩ target used to date in the study of this coherent reaction. The total cross section for coherent neutral-current single π0 production initiated by the νμ flux of the NuMI low-energy beam with mean (mode) Eν of 4.9 GeV (3.0 GeV), is 77.6±5.0(stat)-16.8+15.0(syst)×10-40 cm2 pernucleus. The results are in good agreement with predictions of the Berger-Sehgal model.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Limits on Active to Sterile Neutrino Oscillations from Disappearance Searches in the MINOS, Daya Bay, and Bugey-3 Experiments

Searches 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. Stringent limits on sin22θμe are set over 6 orders of magnitude in the sterile mass-squared splitting Δm412. The sterile-neutrino mixing phase space allowed by the LSND and MiniBooNE experiments is excluded for Δm412<0.8 eV2 at 95% CLs.

43 PARTICLE ACCELERATORS↗

Search for Sterile Neutrinos Mixing with Muon Neutrinos in MINOS

We report results of a search for oscillations involving a light sterile neutrino over distances of 1.04 and 735 km in a νμ-dominated beam with a peak energy of 3 GeV. The data, from an exposure of 10.56×1020 protons on target, are analyzed using a phenomenological model with one sterile neutrino. We constrain the mixing parameters θ24 and Δm412 and set limits on parameters of the four-dimensional Pontecorvo-Maki-Nakagawa-Sakata matrix, |Uμ4|2 and |Uτ4|2, under the assumption that mixing between νe and νs is negligible (|Ue4|2=0). No evidence for νμ→νs transitions is found and we set a world-leading limit on θ24 for values of Δm412≲1 eV2.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Measurement of the Multiple-Muon Charge Ratio in the MINOS Far Detector

The charge ratio, Rμ=Nμ+/Nμ-, 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 Rμ=1.104±0.006(stat)-0.010+0.009(syst). 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.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

The NuMI Neutrino Beam

This 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 design details of individual components are described. Beam monitoring systems and procedures, including the tuning and alignment of the beam and NuMI long-term performance, are also discussed.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Precision Measurement of the Speed of Propagation of Neutrinos using the MINOS Detectors

We report a two-detector measurement of the propagation speed of neutrinos over a baseline of 734 km. The measurement was made with the NuMI beam at Fermilab between the near and far MINOS detectors. The fractional difference between the neutrino speed and the speed of light is determined to be (v/c-1)=(1.0±1.1)×10-6, consistent with relativistic neutrinos.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗