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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

MIP dQ/dx Calibration in DUNE ND-LAr Prototypes with Pixelated Charge Readout

The Deep Underground Neutrino Experiment (DUNE) will be a next-generation long baseline neutrino oscillation experiment that will employ LArTPC technology in a near detector placed at Fermilab and a far detector at the Sanford Underground Research Facility, at a baseline of 1300 km. The DUNE Liquid Argon Near Detector (ND-LAr) design takes into account the high neutrino intensity expected from the beam at the Long-Baseline Neutrino Facility (LBNF): 35 modules, each containing two optically separated time projection chambers, are instrumented with a pixel-based, true 3D charge readout alongside scintillation light traps to disentangle the O(100) interactions expected per 10us beam spill. A robust prototyping program supports ND-LAr’s design: the 2x2 Demonstrator consists of four scaled-down ND-LAr modules exposed to the NuMI beam at Fermilab, and the Full Scale Demonstrator (FSD) is a single ND-LAr module tested with cosmic rays at the University of Bern. We present here an analysis of minimum ionizing particle (MIP) tracks selected from 2x2 beam data and FSD cosmic ray data used to benchmark the pixel-based charge readout simulation and calibration in both detectors, with the ultimate goal of validating the design of DUNE ND-LAr as well as informing future calibration methods. This poster will showcase the dependence of the charge response on track inclination as well as a per-pixel dQ/dX extraction.

Mandujano, Roberto [UC, Irvine]↗
DOE OSTI2025

Using Simulation to Interpret LArS's Results

Scintillation light analysis in liquid argon based neutrino detectors is restrained in capability due to uncertainty in fundamental constants critical to the analysis process. One such property is the Rayleigh scattering length of liquid argon. In the fall of 2023, the TallBo cryostat, located in the Noble Liquid Testing Facility (NLTF) at Fermilab, was used to study the scattering length of liquid argon in the Liquid Argon Scattering (LArS) experiment. Due to systematic errors unknown during measurement analysis, LArS s measurements were quite uncertain. By simulating the LArS experiment, we found that the downturn in detector count rate as a function of liquid argon height at low heights was caused by a misplaced silicon photo multiplier (SiPM). With concentrated effort, we may be able to successfully correct this effect by understanding the relationship between the specified Rayleigh scattering length and the measured attenuation length. With this information and further progression in analysis, we may be able to extract corrected measurements from the LArS data and attain a tangible experimental measurement of the scattering length of liquid argon.

Breaux, Auto D. [Tulane U.]↗
DOE OSTI2020

Measurement of Liquid Argon Scintillation Light Properties by means of an Alpha Source placed inside the CERN 10-PMT LAr Detection System

A particle detection system that exploits the scintillation light produced by ionizing particles in liquid argon (LAr) has been assembled at CERN. The system is based on 10 large-area photomultiplier tubes (PMT) immersed in a 1500-liter dewar filled with liquid argon and equipped with an extendible feed-through and mechanical support for an alpha source (241Am). The position of the source can be changed with respect to the PMT plane in vertical and horizontal directions. Arrays of silicon photomultiplier (SiPM) photodetectors, integrated in the source support, are used for the data acquisition trigger and to define the t0 of the light generation. PMT and SiPM signals can be recorded at different distances and different positions allowing the measurement of some of the LAr scintillation light properties. The system was studied and characterized in detail, and physics results on LAr scintillation properties are expected soon.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2023

Scintillation light detection performance for the DUNE ND-LAr 2 × 2 modules

The Deep Underground Neutrino Experiment (DUNE) will be using a liquid argon time projection chamber (LAr TPC) with optically separated modules in the Near Detector (ND) complex. A prototype experiment, DUNE ND-LAr 2 × 2, is composed of four test modules. They detect ionization charge through a pixel-based readout and scintillation light through fibers in light collection modules and light traps called ArCLights. The light detection performance for two modules of DUNE ND-LAr 2 × 2 that took cosmic ray data at the University of Bern is shown. We present further the role of the 2 × 2 prototype in DUNE and how it is used to demonstrate the reconstruction capabilities of its light detectors in terms of energy thresholds and timing resolution.

47 OTHER INSTRUMENTATION↗
DOE OSTI2024

R&D for LAr + Xe + photosensitive dopants

LArTPCs are the technology of choice for current and future neutrino experiments, including those expected to make eagerly awaited measurements of accelerator neutrino oscillations in the coming decade. This technology provides a large active volume and sensitivity to GeV signals like accelerator neutrinos all the way down to 10s of MeV, covering part of the supernova neutrino spectrum.Expanding the reach of LArTPCs to below the 10 MeV range would substantially enhance the flagship analyses of experiments like DUNE, while potentially enabling the physics of solar neutrinos, dark matter searches, and neutrinoless double beta decay searches.We outline the R&D pathway for photosensitive dopants, whose introduction into the LAr active medium, has the potential to substantially increase ionization yields of LAr detectors and enable the detection of low energy signals in large LArTPCs. This R&D program will demonstrate the feasibility and impacts of introducing doped LAr into current and future neutrino detectors at the kTon scale including the Xenon + photosensitive doping strategy.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2025

Modelling detector-specific reconstruction uncertainties in LAr-TPC

The Short-Baseline Neutrino (SBN) program features three Liquid Argon Time Projection Chamber (LAr-TPC) detectors positioned along the Booster Neutrino Beam (BNB) axis: the Short Baseline Neutrino Near Detector, MicroBooNE, and the ICARUS T600. As the largest operational LAr-TPC, ICARUS T600 serves as the far detector, located 600 m from the BNB target. While its primary goal is to record neutrino events, it also detects other ionizing events, including cosmic rays. This work focuses on analyzing and modeling detector-specific reconstruction uncertainties in LAr-TPC. These inefficiencies, identified during the Pattern Recognition phase handled by the PANDORA algorithm, impact subsequent Particle Fits and Offline Analysis. Specifically, inaccuracies in track reconstruction can lead to significant physical consequences, such as erroneous particle energy estimates and poor Particle Identification (PID), reducing the efficiency of neutrino event characterization. A key issue addressed is split tracks, caused by missing hits or incomplete track stitching by PANDORA. The aim of this internship is to characterize, model, and quantify the impact of split tracks on track reconstruction.

43 PARTICLE ACCELERATORS↗
NASA NTRS1990

The Liquid Annular Reactor System (LARS) propulsion

A concept for very high specific impulse (greater than 2000 seconds) direct nuclear propulsion is described. The concept, termed the liquid annular reactor system (LARS), uses liquid nuclear fuel elements to heat hydrogen propellant to very high temperatures (approximately 6000 K). Operating pressure is moderate (approximately 10 atm), with the result that the outlet hydrogen is virtually 100 percent dissociated to monatomic H. The molten fuel is contained in a solid container of its own material, which is rotated to stabilize the liquid layer by centripetal force. LARS reactor designs are described, together with neutronic and thermal-hydraulic analyses. Power levels are on the order of 200 megawatts. Typically, LARS designs use seven rotating fuel elements, are beryllium moderated, and have critical radii of approximately 100 cm (core L/D approximately equal to 1.5).

Powell, James↗
NASA NTRS2009

Rb-Sr and Sm-Nd Studies of Olivine-Phyric Shergottites RBT 04262 and LAR 06319: Isotopic Evidence for Relationship to Enriched Basaltic Shergottites

RBT 04262 and LAR 06319 are two Martian meteorites recently discovered in Antarctica. Both contain abundant olivines, and were classified as olivine-phyric shergottites. A detailed petrographic study of RBT 04262 suggested it should be reclassified as a lherzolitic shergottite. However, the moderately LREE-depleted REE distribution pattern indicated that it is closely related to enriched basaltic shergottites like Shergotty, Zagami, Los Angeles, etc. In earlier studies of a similarly olivinephyric shergottite NWA 1068 which contains 21% modal olivine, it was shown that it probably was produced from an enriched basaltic shergottite magma by olivine accumulation . As for LAR 06319, recent petrographic studies suggested that it is different from either lherzolitic shergottites or the highly LREE-depleted olivine-phyric shergottites. We performed Rb-Sr and Sm-Nd isotopic analyses on RBT 04262 and LAR 06319 to determine their crystallization ages and Sr and Nd isotopic signatures, and to better understand the petrogenetic relationships between them and other basaltic, lherzolitic and depleted olivine-phyric shergottites.

Nyquist, L.E.↗
DOE OSTI2023

Scintillation light detection performance for the DUNE ND-LAr 2 × 2 modules

The Deep Underground Neutrino Experiment (DUNE) will be using a liquid argon time projection chamber (LAr TPC) with optically separated modules in the Near Detector (ND) complex. A prototype experiment, DUNE ND-LAr 2 × 2, is composed of four test modules. They detect ionization charge through a pixel-based readout and scintillation light through fibers in light collection modules and light traps called ArCLights. The light detection performance for two modules of DUNE ND-LAr 2 × 2 that took cosmic ray data at the University of Bern is shown. We present further the role of the 2 × 2 prototype in DUNE and how it is used to demonstrate the reconstruction capabilities of its light detectors in terms of energy thresholds and timing resolution.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2025

DUNE ND-LAr 2x2 Demonstrator Tests

A modular liquid argon (LAr) Time Projection Chamber (TPC) will be part of the near-detector facility for the Deep Underground Neutrino Experiment (DUNE). Such a TPC is being developed by the ArgonCube collaboration. To demonstrate the feasibility of the LAr DUNE Near Detector, a medium size prototype has been built: the ArgonCube 2x2 Demonstrator. The detector will be placed in the MINOS-ND hall, upstream of the current MINERνA/MINOS-ND locations, at Fermilab. Currently two modules are being tested at the Liquid Argon Test Facility (LArTF), before being place on-axis in the NuMI neutrino beam. The present report will be focused on the work done within the 2x2 Demonstrator group: the first part of the project is focused on the Low Noise AC Power distribution at LArTF, whereas the second is related to the 2x2 demonstrator light readout system tests.

43 PARTICLE ACCELERATORS↗
DOE OSTI2026

Results from the DUNE ND-LAr 2x2 Demonstrator Run 2

The Deep Underground Neutrino Experiment (DUNE) is a cutting-edge, long-baseline experiment under construction in the United States, based on large liquid-argon time projection chambers (LArTPCs). The DUNE Near Detector LArTPC (ND-LAr) will employ a novel modular architecture using a pixelated LArPix charge readout. To validate this design and characterize detector response, the 2×2 demonstrator—an array of eight optically isolated LArTPC modules—was deployed at Fermilab in 2024. During winter 2025, the 2x2 demonstrator was operated for a second data-taking campaign (Run 2) with the aim of studying the low-energy response of the detector. Run 2 focused on calibration and response studies using a suite of deployed radioactive sources. Gamma sources (²²Na, ⁶⁰Co, and ⁸⁸Y) were used to probe module-to-module performance variations, energy resolution, and calibrations. Neutron sources (AmBe and a pulsed neutron generator) enabled studies of neutron interactions in liquid argon, including inelastic scatters and neutron capture signals, relevant for low-energy backgrounds and detector modeling. In addition, the detector was doped with ²²⁰Rn, providing Bi–Po coincidence signals that allow precise calibration of the charge and scintillation response. This poster will present results from these calibration campaigns. These studies provide critical validation of the ND-LAr modular LArTPC concept and inform calibration and reconstruction strategies for the full DUNE near detector.

Mora-Lepin, Luis [Florida State U.] (ORCID:0000000↗
DOE OSTI2026

Studying MeV Scale Neutron Interactions in DUNE ND-LAr 2x2 Demonstrator

The Deep Underground Neutrino Experiment (DUNE) is a long-baseline neutrino oscillation experiment designed to make high-precision measurements of neutrino oscillation parameters and probe for new physics using a neutrino beam produced at Fermilab and measured at a near detector complex and a far detector located 1,300 km away at the Sanford Underground Research Facility. Precise neutrino energy reconstruction is essential for these measurements, with neutron production in neutrino–argon interactions representing a significant source of systematic uncertainty, as neutrons can carry away significant energy, making their detection and characterization crucial. DUNE’s near detector complex includes ND-LAr, a Liquid Argon Time Projection Chamber (LArTPC) detector designed to mirror the far detector technology and constrain neutrino–argon interaction systematics. The DUNE 2x2 Demonstrator, a pixelated LArTPC based on the ArgonCube design, serves as a prototype for ND-LAr. During 2x2 operations from October to November 2026, an Americium–Beryllium (AmBe) neutron source was deployed near the detector cryostat to obtain a high-statistics sample of neutron interactions. This poster presents progress in studying MeV-scale neutron interactions in this dataset by identifying de-excitation gammas from neutron capture on argon, providing a method for neutron identification and charge readout system calibration in future DUNE detectors.

Mao, Edgar [Syracuse U.] (ORCID:0009000600893306)↗
NASA NTRS2015

Peology and Geochemistry of New Paired Martian Meteorites 12095 and LAR 12240

The meteorites LAR 12095 and LAR 12240 are believed to be paired Martian meteorites and were discovered during the Antarctic Search for Meteorites (ANSMET) 2012-2013 Season at Larkman Nunatak. The purpose of this study is to characterize these olivine-phyric shergottites by analyzing all mineral phases for major, minor and trace elements and examining their textural relationships. The goal is to constrain their crystallization history and place these shergottites among other Martian meteorites in order to better understand Martian geological history.

Funk, R. C.↗
NASA NTRS2000

LARS: Did You Know?

The Library, Archives, and Records Section (LARS) will host its annual Open House for JPL employees and on-site contractors Tuesday, June 27 through Thursday, June 29, 2000.

library archives records LARS↗
NASA NTRS1985

A test of the Suits vegetative-canopy reflectance model with LARS soybean-canopy reflectance data

The Suits vegetative-canopy reflectance model is tested with an extensive set of field reflectance measurements made by the Laboratory for Application of Remote Sensing (LARS) for soybean canopies. The model is tested for the full hemisphere of observer directions as well as the nadir direction. The results show moderate agreement for the visible channels of the Landsat MSS and poor agreement in the near-infrared channel of Landsat MSS. An analysis of errors is given.

Chance, J. E.↗
NASA NTRS2010

A More Reduced Mantle Source for Enriched Shergottites; Insights from the Olivine-Phyric Shergottite Lar 06319

A detailed petrographic study of melt inclusions and Cr-Fe-Ti oxides of LAR 06319 leads to two main conclusions: 1) this enriched oxidized olivine- phyric shergottite represents nearly continuous crystallization of a basaltic shergottite melt, 2) the melt became more oxidized during differentiation. The first crystallized mineral assemblages record the oxygen fugacity which is closest to that of the melt s mantle source, and which is lower than generally attributed to the enriched shergottite group.

Peslier, A. H.↗