A. M. Salyapongse
A5112925926- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Radiation Dose and Imaging
- Advanced X-ray and CT Imaging
- Medical Imaging Techniques and Applications
- Atomic and Subatomic Physics Research
- Astrophysics and Cosmic Phenomena
- Dental Radiography and Imaging
- X-ray Spectroscopy and Fluorescence Analysis
- Radiation Detection and Scintillator Technologies
- Nuclear Physics and Applications
- Particle Detector Development and Performance
University of Wisconsin–Madison
2023-2025
Carnegie Mellon University
2021-2023
Wisconsin Institutes for Discovery
2023
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,...
Objective Patient positioning during clinical practice can be challenging, and mispositioning leads to a change in CT number. number fluctuation was assessed single-energy (SE) EID, dual-energy (DE) deep silicon photon-counting detector (PCD) over water-equivalent diameter (WED) with different mispositions. Methods A phantom containing five clinically relevant inserts (Mercury Phantom, Gammex) scanned on EID PCD prototype at vertical positions of 0, 4, 8, 12 cm. scans used 120 kV rapid...
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...
Variable beam hardening based on patient size causes variation in CT numbers for energy-integrating detector (EID) CT. Photon-counting (PCD) more accurately determines effective energy, potentially improving number reliability.
The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory is a pulsed source of neutrons and, as by-product this operation, an intense neutrinos via stopped-pion decay. COHERENT collaboration uses to investigate coherent elastic neutrino-nucleus scattering and other physics with suite detectors. This work includes description our geant4 simulation neutrino production the SNS flux calculation which informs studies. We estimate uncertainty $\ensuremath{\sim}10%$ level based on...
We report on the technical design and expected performance of a 592 kg heavy-water-Cherenkov detector to measure absolute neutrino flux from pion-decay-at-rest source at Spallation Neutron Source (SNS) Oak Ridge National Laboratory (ORNL). The will be located roughly 20 m SNS target with better than 5% statistical uncertainty in 2 years. This heavy-water serve as first module two-module system ultimately 2-3% both First Target Station planned Second SNS. significantly reduce dominant...
Abstract We present results of several measurements CsI[Na] scintillation response to 3–60 keV energy nuclear recoils performed by the COHERENT collaboration using tagged neutron elastic scattering experiments and an endpoint technique. Earlier results, used estimate coherent neutrino-nucleus (CEvNS) event rate for first observation this process achieved at Spallation Neutron Source (SNS), have been reassessed. discuss corrections identified systematic effects update respective uncertainty...
Abstract Background Quantitative CT imaging, particularly iodine and calcium quantification, is an important CT-based biomarker. Purpose This study quantifies sources of errors in quantitative imaging both single-energy spectral CT. Materials methods work examines the theoretical relationship between numbers, linear attenuation coefficient, material quantification. We derive four understandings: (1) numbers are not proportional with element mass vivo, (2) only when contained a voxel pure...
Using neutrinos produced at the Spallation Neutron Source (SNS) Oak Ridge National Laboratory (ORNL), COHERENT collaboration has studied $\mathrm{Pb}({\ensuremath{\nu}}_{e},\mathrm{X}n)$ process with a lead neutrino-induced-neutron (NIN) detector. Data from this detector are fit jointly previously collected data on process. A combined analysis of two datasets yields cross section that is ${0.29}_{\ensuremath{-}0.16}^{+0.17}$ times predicted by MARLEY event generator using...
The COHERENT experiment located in Neutrino Alley at the Spallation Neutron Source (SNS), Oak Ridge National Laboratory (ORNL), has made world's first two measurements of coherent elastic neutrino-nucleus scattering (CEvNS), on CsI and argon, using neutrinos produced SNS. collaboration continues to pursue CEvNS various targets as well additional studies inelastic interactions, searches for accelerator-produced dark matter (DM) physics beyond Standard Model, uniquely high-quality...
We present the analysis and results of first dataset collected with MARS neutron detector deployed at Oak Ridge National Laboratory Spallation Neutron Source (SNS) for purpose monitoring characterizing beam-related (BRN) background COHERENT collaboration. was positioned next to COH-CsI coherent elastic neutrino-nucleus scattering in SNS basement corridor. This is location closest proximity target thus, highest neutrino flux, but it also well shielded from BRN flux by infill concrete gravel....
We use data from the COHERENT CsI[Na] scintillation detector to constrain sub-GeV leptophobic dark matter models. This was built observe low-energy nuclear recoils coherent elastic neutrino-nucleus scattering. These capabilities enable searches for particles produced at Spallation Neutron Source mediated by a vector portal particle with masses between 2 and 400 MeV/c2. No evidence is observed limit on mediator coupling quarks placed. constraint improves upon previous results two orders of...
The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory is a pulsed source of neutrons and, as byproduct this operation, an intense neutrinos via stopped-pion decay. COHERENT collaboration uses to investigate coherent elastic neutrino-nucleus scattering and other physics with suite detectors. This work includes description our Geant4 simulation neutrino production the SNS flux calculation which informs studies. We estimate uncertainty about 10% based on validation against...
Purpose: We investigated spatial resolution loss away from isocenter for a prototype deep silicon photon-counting detector (PCD) CT scanner and compare with clinical energy-integrating (EID) scanner. Materials Methods: performed three scans on wire phantom at four positions (isocenter, 6.7, 11.8, 17.1 cm off isocenter). The acquisition modes were 120 kV EID CT, high-definition (HD) PCD CT. HD mode used double the projection view angles per rotation as “regular” scan mode. diameter of was...
Using neutrinos produced at the Spallation Neutron Source (SNS) Oak Ridge National Laboratory (ORNL), COHERENT collaboration has studied Pb($ν_e$,X$n$) process with a lead neutrino-induced-neutron (NIN) detector. Data from this detector are fit jointly previously collected data on process. A combined analysis of two datasets yields cross section that is $0.29^{+0.17}_{-0.16}$ times predicted by MARLEY event generator using experimentally-measured Gamow-Teller strength distributions,...
Description of the data release 10.13139/OLCF/1969085 (https://doi.ccs.ornl.gov/ui/doi/426) from measurements CsI[Na] response to low energy nuclear recoils by COHERENT collaboration. The corresponds results published in "D. Akimov et al 2022 JINST 17 P10034". We share form raw ADC waveforms, provide benchmark values, and plots enhance transparency reproducibility our results. This document describes contents as well guidance on use data.
We use data from the COHERENT CsI[Na] scintillation detector to constrain sub-GeV leptophobic dark matter models. This was built observe low-energy nuclear recoils coherent elastic neutrino-nucleus scattering. These capabilities enable searches for particles produced at Spallation Neutron Source mediated by a vector portal particle with masses between 2 and 400 MeV/c$^2$. No evidence is observed limit on mediator coupling quarks placed. constraint improves upon previous results two orders of...