Publications by authors named "Rameika R"

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 PDF

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 PDF

The 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 PDF
Article Synopsis
  • The NOvA experiment improved measurements of muon neutrino (ν_{μ}) to electron neutrino (ν_{e}) transitions, detecting 33 ν_{e} candidates amid a background of 8.2±0.8.
  • Combining this data with recent ν_{μ} disappearance results and reactor experiment constraints,
  • the study disfavored the inverted mass hierarchy scenario for neutrino mixing at over 93% confidence level across all values of the CP-violating phase (δ_{CP}).
View Article and Find Full Text PDF

This 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 PDF

We 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 PDF

This Letter reports on a search for nu(mu) --> nu(e) transitions by the MINOS experiment based on a 3.14x10(20) protons-on-target exposure in the Fermilab NuMI beam. We observe 35 events in the Far Detector with a background of 27+/-5(stat)+/-2(syst) events predicted by the measurements in the Near Detector.

View Article and Find Full Text PDF

We report the first detailed comparisons of the rates and spectra of neutral-current neutrino interactions at two widely separated locations. A depletion in the rate at the far site would indicate mixing between nu(mu) and a sterile particle. No anomalous depletion in the reconstructed energy spectrum is observed.

View Article and Find Full Text PDF

A search for a sidereal modulation in the MINOS near detector neutrino data was performed. If present, this signature could be a consequence of Lorentz and CPT violation as predicted by the effective field theory called the standard-model extension. No evidence for a sidereal signal in the data set was found, implying that there is no significant change in neutrino propagation that depends on the direction of the neutrino beam in a sun-centered inertial frame.

View Article and Find Full Text PDF
Article Synopsis
  • The MINOS experiment observed muon neutrinos over two years from the Fermilab NuMI beam, confirming quantum-mechanical oscillations of neutrino flavors.
  • Results showed a mass splitting of |Deltam2| = (2.43+/-0.13) x 10(-3) eV2 and a high mixing angle (sin2(2theta) > 0.90), indicating strong neutrino oscillation.
  • The findings also reject two alternative explanations for neutrino disappearance—decays into lighter particles and quantum decoherence—at statistically significant levels (3.7 and 5.7 standard deviations).
View Article and Find Full Text PDF

This Letter reports results from the MINOS experiment based on its initial exposure to neutrinos from the Fermilab NuMI beam. The rates and energy spectra of charged current nu(mu) interactions are compared in two detectors located along the beam axis at distances of 1 and 735 km. With 1.

View Article and Find Full Text PDF

Based on 1.35 x 10(6) polarized Xi(-) events, we measure the parameter phi(Xi) to be -1.61 degrees +/-2.

View Article and Find Full Text PDF

A search for direct CP violation in the nonleptonic decays of hyperons has been performed. In comparing the product of the decay parameters, alpha(Xi)alpha(Lambda), in terms of an asymmetry parameter, A(XiLambda), between hyperons and antihyperons in the charged Xi-->Lambdapi and Lambda-->ppi decay sequence, we found no evidence of direct CP violation. The parameter A(XiLambda) was measured to be 0.

View Article and Find Full Text PDF