T. Wongjirad
A5038967300- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Astrophysics and Cosmic Phenomena
- Particle Detector Development and Performance
- Atomic and Subatomic Physics Research
- Radiation Detection and Scintillator Technologies
- Particle accelerators and beam dynamics
- Nuclear Physics and Applications
- Muon and positron interactions and applications
- Quantum, superfluid, helium dynamics
- Computational Physics and Python Applications
- Radio Frequency Integrated Circuit Design
- Quantum Chromodynamics and Particle Interactions
- Superconducting Materials and Applications
- Mass Spectrometry Techniques and Applications
- Quantum Information and Cryptography
- Atmospheric Ozone and Climate
- Atomic and Molecular Physics
- Cold Atom Physics and Bose-Einstein Condensates
- High-Energy Particle Collisions Research
- Advanced Fluorescence Microscopy Techniques
- Quantum Mechanics and Applications
- Nuclear physics research studies
- Medical Image Segmentation Techniques
Tufts University
2018-2025
University of Cincinnati
2020-2024
New Mexico State University
2024
Colorado State University
2023-2024
Louisiana State University
2024
The NSF AI Institute for Artificial Intelligence and Fundamental Interactions
2024
Nankai University
2024
Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas
2023
University of Chicago
2020-2022
University of California, Santa Barbara
2020-2022
The results of the third phase Super-Kamiokande solar neutrino measurement are presented and compared to first second results. With improved detector calibrations, a full simulation, analysis methods, systematic uncertainty on total flux is estimated be ?2.1%, which about two thirds for Super-Kamiokande. observed 8B in 5.0 20 MeV electron energy region 2.32+/-0.04 (stat.)+/-0.05 (sys.) *10^6 cm^-2sec^-1, agreement with previous measurements. A combined oscillation carried out using SK-I, II,...
After important upgrades to the experiment, Super-Kamiokande collaboration returns measuring solar mixing angle and mass splitting $\mathrm{\ensuremath{\Delta}}\phantom{\rule{0}{0ex}}{m}_{12}^{2}$. By focusing on low-energy ${}^{8}B$ neutrinos, is able single out neutrinos that undergo flavor conversion only through vacuum oscillations. The results are currently most precise values for mass-difference parameters relevant neutrino
Super-Kamiokande (SK) can search for weakly interacting massive particles (WIMPs) by detecting neutrinos produced from WIMP annihilations occurring inside the Sun. In this analysis, we include neutrino events with interaction vertices in detector addition to upward-going muons surrounding rock. Compared previous result, which used only, signal acceptances light (few−GeV/c2−200−GeV/c2) WIMPs are significantly increased. We fit 3903 days of SK data contribution annihilation found no...
An analysis of atmospheric neutrino data from all four run periods \superk optimized for sensitivity to the mass hierarchy is presented. Confidence intervals $\Delta m^2_{32}$, $\sin^2 \theta_{23}$, \theta_{13}$ and $\delta_{CP}$ are presented normal inverted hypotheses based on alone. Additional constraints reactor $\theta_{13}$ published binned T2K muon disappearance electron appearance added fit give enhanced above parameters. Over range parameters allowed at 90% confidence level, favored...
We report the first measurement of coherent elastic neutrino-nucleus scattering (CEvNS) on argon using a liquid detector at Oak Ridge National Laboratory Spallation Neutron Source. Two independent analyses prefer CEvNS over background-only null hypothesis with greater than $3\ensuremath{\sigma}$ significance. The measured cross section, averaged incident neutrino flux, is $(2.2\ifmmode\pm\else\textpm\fi{}0.7)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}39}\text{ }\text{...
We have searched for proton decay via $p \rightarrow e^{+} \pi^{0}$ and \mu^{+} using Super-Kamiokande data from April 1996 to March 2015, 0.306 megaton$\cdot$years exposure in total. The atmospheric neutrino background rate IV is reduced almost half that of phase I-III by tagging neutrons associated with interactions. reach the lifetime further enhanced introducing new signal criteria select a hydrogen atom. No candidates were seen search. Two passed all selection been observed, but these...
We measured the cross section of coherent elastic neutrino-nucleus scattering (CEvNS) using a CsI[Na] scintillating crystal in high flux neutrinos produced at Spallation Neutron Source Oak Ridge National Laboratory. New data collected before detector decommissioning have more than doubled dataset since first observation CEvNS, achieved with this detector. Systematic uncertainties also been reduced an updated quenching model, allowing for improved precision. With these analysis improvements,...
A new Super-Kamiokande (SK) search for Supernova Relic Neutrinos (SRNs) was conducted using 2853 live days of data. Sensitivity is now greatly improved compared to the 2003 SK result, which placed a flux limit near many theoretical predictions. This more detailed analysis includes variety improvements such as increased efficiency, lower energy threshold, and an expanded data set. New combined upper limits on SRN are between 2.8 3.0 nu_e cm^-2 s^-1 > 16 MeV total positron (17.3 E_nu).
Are there more than three types of neutrinos in nature ? Some experiments show that should exist at least one type, called sterile neutrinos. Using atmospheric neutrino data from the Super-Kamiokande experiment, authors find new limits on oscillations.
The ArgoNeuT liquid argon time projection chamber has collected thousands of neutrino and anti-neutrino events during an extended run period in the NuMI beam-line at Fermilab. This paper focuses on main aspects detector layout related technical features, including cryogenic equipment, chamber, read-out electronics, off-line data treatment. commissioning phase, physics run, first event displays are also reported. characterization working parameters data-taking, ionization electron drift...
We present the result of an indirect search for high energy neutrinos from WIMP annihilation in Sun using upward-going muon (upmu) events at Super-Kamiokande. Datasets SKI-SKIII (3109.6 days) were used analysis. looked excess neutrino signal as compared with expected atmospheric background three upmu categories: stopping, non-showering, and showering. No significant was observed. The 90% C.L. upper limits flux induced by WIMPs 100 GeV/c$^2$ 6.4$\times10^{-15}$ cm$^{-2}$ sec$^{-1}$...
We have searched for proton decay via $p \rightarrow \nu K^{+}$ using Super-Kamiokande data from April 1996 to February 2013, 260 kiloton$\cdot$year exposure in total. No evidence this mode is found. A lower limit of the lifetime set $5.9 \times 10^{33}$ years at 90% confidence level.
A comprehensive study on the atmospheric neutrino flux in energy region from sub-GeV up to several TeV using Super-Kamiokande water Cherenkov detector is presented this paper. The and azimuthal spectra of ${\nu}_e+{\bar{\nu}}_e$ ${\nu}_{\mu}+{\bar{\nu}}_{\mu}$ fluxes are measured. obtained an iterative unfolding method by combining various event topologies with differing responses. depending zenith angle, their modulation geomagnetic effects, also studied. predicted east-west asymmetry...
We report an indication that the elastic scattering rate of solar $^8$B neutrinos with electrons in Super-Kamiokande detector is larger when pass through Earth during nighttime. determine day/night asymmetry, defined as difference average day and night divided by those two rates, to be $(-3.2\pm1.1(\text{stat})\pm0.5(\text{syst}))\%$, which deviates from zero 2.7 $\sigma$. Since process mostly sensitive electron-flavored neutrinos, a non-zero asymmetry implies flavor oscillations are...
The COHERENT Collaboration searched for scalar dark matter particles produced at the Spallation Neutron Source with masses between 1 and 220 MeV/c^{2} using a CsI[Na] scintillation detector sensitive to nuclear recoils above 9 keV_{nr}. No evidence is found we thus place limits on allowed parameter space. With this low-threshold detector, are coherent elastic scattering nuclei. cross section process orders of magnitude higher than other processes historically used accelerator-based...
Liquid Xenon (LXe) is an excellent material for experiments designed to detect dark matter in the form of Weakly Interacting Massive Particles (WIMPs). A low energy detection threshold essential a sensitive WIMP search. The understanding relative scintillation efficiency (Leff) and ionization yield nuclear recoils LXe limited energies below 10 keV. In this paper, we present new measurements that extend down 4 keV, finding Leff decreases with decreasing energy. We also measure quenching due...
Super-Kamiokande atmospheric neutrino data were fit with an unbinned maximum likelihood method to search for the appearance of tau leptons resulting from interactions oscillation-generated neutrinos in detector. Relative expectation unity, normalization is found be 1.42 ± 0.35(stat)(-0.12)(+0.14)(syst) excluding no-tau-appearance hypothesis, which would zero, at 3.8σ level. We estimate that 180.1 44.3(stat)(-15.2)(+17.8) (syst) produced 22.5 kton fiducial volume detector by during 2806 day...
We present a search for differences in the oscillations of antineutrinos and neutrinos Super-Kamiokande-I, -II, -III atmospheric neutrino sample. Under two-flavor disappearance model with separate mixing parameters between antineutrinos, we find no evidence difference oscillation parameters. Best-fit antineutrino is found to be at (Δm2,sin2 2θ)=(2.0×10(-3) eV2, 1.0) consistent overall Super-K measurement.
A search for neutrino oscillations induced by Lorentz violation has been performed using 4,438 live-days of Super-Kamiokande atmospheric data. The is included in addition to standard three-flavor the nonperturbative model extension (SME), allowing use full range path lengths, ranging from 15 12,800 km, and energies 100 MeV more than TeV search. No evidence was observed, so limits are set on renormalizable isotropic SME coefficients eμ, μτ, eτ sectors, improving existing up 7 orders magnitude...
The COHERENT experiment is well poised to test sub-GeV dark matter models using low-energy recoil detectors sensitive coherent elastic neutrino-nucleus scattering (CEvNS) in the $\pi$-DAR neutrino beam produced by Spallation Neutron Source. We show how a planned 750-kg liquid argon scintillation detector would place leading limits on scalar light models, over two orders of magnitude mass, for particles through vector and leptophobic portals absence other effects beyond standard model....
We present the results of searches for nucleon decay via bound neutron to antineutrino plus pizero and proton piplus using data from a combined 172.8 kiloton-years exposure Super-Kamiokande-I, -II, -III. set lower limits on partial lifetime each these modes. For pizero, is >1.1x10^{33} years; piplus, >3.9x10^{32} years at 90% confidence level.