Session Z12: Neutino Interactions II

Live

Long-baseline neutrino oscillation experiments such as T2K (Tokai-to-Kamioka) and DUNE (Deep Underground Neutrino Experiment) which aim at precise measurements of the CP violation phase rely on the modeling of the neutrino interaction on nuclei. A major systematic uncertainty of the neutrino interaction modeling comes from the blindness of the detector to the neutrons in the final state. T2K and DUNE plan to introduce a three-dimensional projection scintillator tracker as part of their Near detector systems. Such a detector consists of a large number of 1 cm x 1 cm x 1 cm scintillator cubes with three orthogonal wavelength shifting fibers crossing through each cube. Benefited by the good timing resolution and fine granularity, this detector will be capable of measuring neutrons including its kinetic energy in neutrino interactions on an event-by-event basis. In order to fully demonstrate the neutron detection capability and optimize the tracker design, two prototypes have been assembled and exposed to neutron beam test in Los Alamos National Laboratory in December 2020. In this talk, the detail of the beam test will be described and some preliminary results will be shared.   

Live

The charged-current process($\nu_\mu $A$\rightarrow \mu$X) is analyzed using the MINER$\nu$A detector in the medium energy(ME) NuMI beam. $\nu_\mu$ inclusive interactions in the hydrocarbon scintillator tracker are used to study the nuclear effects at low three-momentum transfer, q3, focusing mainly on Meson Exchange Current(MEC) and resonant(RES) interactions. For the RES events we studied the effects of Pauli Blocking, Removal Energy, effects of quasi-elastic(QE) Random Phase Approximation on RES, single pion production models such as the Kabirnezhad Model and others. The MEC part is studied using the SuSA model for MEC and QE with the Bodek-Ritchie tail correction. We compare the MINER$\nu$A reconstructed distribution with the GENIE simulation with the goal of measuring the flux integrated differential 2D cross section in an extended $q_3$ range with the ME beam.   

Live

Identifying Cherenkov photons produced when charged particles interact with scintillators provides additional information about the interaction, including directionality and particle identification, while maintaining the excellent energy and position resolution typical of scintillator detectors. Dichroicons achieve this by spectrally sorting photons with a Winston cone made from dichroic filters, which reflects photons inconsistent with typical scintillation spectra to one PMT, and passes other photons to another PMT. A simulation model of dichroicon prototypes has been implemented in the GPU-enabled photon Monte Carlo package Chroma. This model is used to evaluate the background rejection, particle identification, and direction reconstruction performance of a large liquid scintillator detector instrumented with dichroicons.   

Live

Precision measurements of coherent elastic neutrino-nucleus scattering (CEvNS) will allow a broad collection of physics studies ranging from improving constraints on non-standard neutrino interactions to probing nuclear structure. Following initial CEvNS measurements on CsI and Ar, the COHERENT experiment is entering an era of precision measurements. Current COHERENT measurements are limited by the 10~\% uncertainty on the neutrino flux from the pion decay-at-rest neutrino source at the Oak Ridge National Laboratory Spallation Neutron Source (SNS). To reduce this uncertainty, a 592~kg heavy-water demonstrator has been designed to measure the absolute neutrino flux from the SNS making use of the well-understood $D+\nu_{e}$ cross section. The first of a planned 2-detector module, the demonstrator will measure the neutrino flux with better than 5~\% statistical precision in 2~SNS-years of running. In this talk I will present the D${}_{2}$O detector design and discuss the expanded physics sensitivity of CEvNS detectors at the SNS with an improved understanding of the neutrino flux.   

Live

The Short Baseline Near Detector (SBND), a 112 ton liquid argon time projection chamber detector, is the near detector of the Short Baseline Neutrino program at Fermilab. Due to its proximity to the neutrino source (110 m) SBND is sensitive to some distinctive characteristics. Here we present SBND-PRISM: an intrinsic and unique feature of the SBND experiment. Since the neutrino beam direction is offset from the center of SBND, some regions of the detector are exposed to neutrinos that are off-axis from the beam direction. This “prism”-like feature allows sampling of multiple neutrino fluxes using the same SBND detector. SBND-PRISM can be utilized to study distinctive neutrino-nucleus interaction and exotic physics signals.   

Live

In the Deep Underground Neutrino Experiment (DUNE), achieving the physics sensitivity for $\delta_{CP}$ requires a precision detector calibration that constrains the uncertainties from relevant detector response parameters. ``Standard candle`` calibration sources are needed to assess the effectiveness of the detector model, but conventional methods are difficult due to the deep underground location and the large scale of the far detector. One of the novel ways is to inject neutrons into the liquid argon far detector using a Deuterium-Deuterium neutron generator. We are currently developing a Pulsed Neutron Source (PNS) system that could be externally placed outside the far detector cryostat for detector calibration. The system will inject neutrons across the entire detector volume and provide neutron capture signals with a fixed energy deposition of 6.1 MeV in the form of multi-gamma cascades. This presentation will include a description of the PNS system and the neutron generator test results at ProtoDUNE.   

Live

The Deep Underground Neutrino Experiment (DUNE) is a next-generation long-baseline neutrino experiment. Among the goals of the experiment are measurements of CP violation and neutrino mass hierarchy using a high power neutrino beam produced at Fermilab. The ProtoDUNE-SP is a prototype of the DUNE far detector, located at the CERN Neutrino Platform. ProtoDUNE-SP comprises a single-phase Liquid-Argon Time Projection Chamber (LArTPC) and a Photon Detector System (PDS). In DUNE, calorimetry of electromagnetic showers (EMS) is a key element in the analysis to separate signal from the background, in electron neutrino interactions with a shower in the final state. Many of the processes observed in ProtoDUNE-SP involve EMS events, so it is crucial to have a good understanding of them. In this talk we discuss the correlation between the electron beam energy and the responses from both the LArTPC ans the PDS. We also show the status of the current work in ProtoDUNE-SP regarding the determination of the achievable resolution in the energy measurement of EMS. Perspectives on the enhancements in calorimetry using the combination of charge and light are also presented.   

Live

The Dichroicon, a Winston-style light concentrator built out of dichroic reflectors, achieves Cherenkov/scintillation separation with minimal photon loss by utilizing a technique called spectral photon sorting. This technique works by diverting long and short wavelength photons to separate photomultiplier tubes (PMTs). This separation allows for the identification of a pure population of Cherenkov photons outside of typical scintillation spectra while still detecting the large amount of scintillation needed for position and energy reconstruction. The separate identification of Cherenkov photons in a bright liquid scintillator provides extra information about the interaction of charged particles with the target, as such photons carry directionality and their ratio to scintillation light can be used for particle identification. Here we discuss reconstruction results in simulations of a next-generation liquid scintillator detector fitted with Dichroicons.