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DOE OSTI2020

Materials Data on CsY(NbBr3)6 by Materials Project

CsY(NbBr3)6 crystallizes in the trigonal P-31c space group. The structure is three-dimensional. Cs1+ is bonded in a 12-coordinate geometry to twelve Br1- atoms. There are six shorter (4.08 Å) and six longer (4.19 Å) Cs–Br bond lengths. Y3+ is bonded to six equivalent Br1- atoms to form YBr6 octahedra that share corners with six equivalent NbBr5 square pyramids. All Y–Br bond lengths are 2.86 Å. Nb+2.33+ is bonded to five Br1- atoms to form distorted NbBr5 square pyramids that share a cornercorner with one YBr6 octahedra and corners with four equivalent NbBr5 square pyramids. The corner-sharing octahedral tilt angles are 45°. There are a spread of Nb–Br bond distances ranging from 2.61–3.00 Å. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 2-coordinate geometry to two equivalent Nb+2.33+ atoms. In the second Br1- site, Br1- is bonded in a 2-coordinate geometry to one Cs1+, one Y3+, and one Nb+2.33+ atom. In the third Br1- site, Br1- is bonded in a 2-coordinate geometry to one Cs1+ and two equivalent Nb+2.33+ atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on CsY(WO4)2 by Materials Project

CsY(WO4)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Cs1+ is bonded in a 12-coordinate geometry to ten O2- atoms. There are a spread of Cs–O bond distances ranging from 2.97–3.09 Å. Y3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Y–O bond distances ranging from 2.30–2.36 Å. W6+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing WO6 octahedra. The corner-sharing octahedral tilt angles are 40°. There are a spread of W–O bond distances ranging from 1.84–2.16 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Cs1+ and two equivalent W6+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Cs1+, one Y3+, and one W6+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Cs1+, one Y3+, and two equivalent W6+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Cs1+, one Y3+, and one W6+ atom.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on CsY(BH4)4 by Materials Project

CsY(BH4)4 crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. Cs1+ is bonded in a 8-coordinate geometry to eight equivalent H+0.50+ atoms. There are four shorter (3.19 Å) and four longer (3.36 Å) Cs–H bond lengths. Y3+ is bonded in a 12-coordinate geometry to twelve H+0.50+ atoms. There are eight shorter (2.35 Å) and four longer (2.36 Å) Y–H bond lengths. B3- is bonded in a tetrahedral geometry to four H+0.50+ atoms. There is one shorter (1.20 Å) and three longer (1.24 Å) B–H bond length. There are four inequivalent H+0.50+ sites. In the first H+0.50+ site, H+0.50+ is bonded in a distorted single-bond geometry to one Y3+ and one B3- atom. In the second H+0.50+ site, H+0.50+ is bonded in a single-bond geometry to one Y3+ and one B3- atom. In the third H+0.50+ site, H+0.50+ is bonded in a single-bond geometry to two equivalent Cs1+ and one B3- atom. In the fourth H+0.50+ site, H+0.50+ is bonded in a single-bond geometry to one Y3+ and one B3- atom.

36 MATERIALS SCIENCE↗

DOE OSTI2026

Report on Coastal Structure Integrated Wave Energy Converters (CSI-WECs)

This report investigates a largely underexplored, and underexploited, application for wave energy: coastal structure integrated wave energy converters (CSI-WECs). These WEC types have significant potential to rapidly advance the wave energy industry while addressing the challenges of coastal community resiliency and marine energy integration and application, and the urgent need for increased coastal protection. To further support the value proposition investigation of this work, three wave energy developers agreed to conduct an energy production analysis of their technology for the four sites identified. Additionally, a geographic information system-based tool was developed that supports efficient and comprehensive site assessment for optimal and high-value deployments.

16 TIDAL AND WAVE POWER↗

DOE OSTI2022

Measurement of scintillation response of CsI[Na] to low-energy nuclear recoils by COHERENT

Here, we present results of several measurements of 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 to estimate the coherent elastic neutrino-nucleus scattering (CEvNS) event rate for the first observation of this process achieved by COHERENT at the Spallation Neutron Source (SNS), have been reassessed. We discuss corrections for the identified systematic effects and update the respective uncertainty values. The impact of updated results on future precision tests of CEvNS is estimated. We scrutinize potential systematic effects that could affect each measurement. In particular we confirm the response of the H11934-200 Hamamatsu photomultiplier tube (PMT) used for the measurements presented in this study to be linear in the relevant signal scale region.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2024

Accessing new physics with an undoped, cryogenic CsI CEvNS detector for COHERENT at the SNS

We consider the potential for a 10 kg undoped cryogenic CsI detector operating at the Spallation Neutron Source to measure coherent elastic neutrino-nucleus scattering and its sensitivity to discover new physics beyond the standard model (BSM). Through a combination of increased event rate, lower threshold, and good timing resolution, such a detector would significantly improve on past measurements. We considered tests of several BSM scenarios such as neutrino nonstandard interactions and accelerator-produced dark matter. This detector’s performance was also studied for relevant questions in nuclear physics and neutrino astronomy, namely the weak charge distribution of Cs and I nuclei and detection of neutrinos from a core-collapse supernova. Published by the American Physical Society 2024

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2022

First operation of undoped CsI directly coupled with SiPMs at 77 K

Abstract The light yield of a small undoped cesium iodide (CsI) crystal directly coupled with two silicon photomultipliers (SiPMs) at about 77 Kelvin was measured to be $$43.0 \pm 1.1$$ 43.0 ± 1.1 photoelectrons (PE) per keV electron-equivalent (keV $$_\text {ee}$$ ee ) using X and $$\gamma $$ γ -ray peaks from an $$^{241}$$ 241 Am radioactive source from 18 to 60 keV. The high light yield together with some other technical advantages illustrate the great potential of this novel combination for neutrino and low-mass dark matter detection, particularly at accelerator-based neutrino sources, where random background can be highly suppressed by requiring coincident triggers between SiPMs and beam pulse timing signals. Some potential drawbacks of using cryogenic SiPMs instead of photomultiplier tubes (PMTs) were identified, such as worse energy resolution and optical cross-talks between SiPMs. Their influence to rare-event detection was discussed and possible solutions were provided.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2023

COHERENT Collaboration data release from the measurements of CsI[Na] response to nuclear recoils

The data release from the measurements of the CsI[Na] response to low energy nuclear recoils by the COHERENT collaboration. The release corresponds to the results published in 'D. Akimov et al 2022 JINST 17 P10034.' We share the data in the form of raw ADC waveforms, provide benchmark subselections and event reconstruction scripts to enhance the transparency and reproducibility of our results.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2026

AmeriFlux US-WT2 Stratford CSI

This is the AmeriFlux version of the carbon flux data for the site US-WT2 Stratford CSI. Site Description - Winter annual forage production system with grazing

Bednarz, Craig [West Texas A&M University]↗

NASA NTRS1964

The Fluorescent Decay of CsI(T1) Excited by Charged Particles

The fluorescence from a CsI(0.08% T1) scintillator excited by charged particles which come to a stop within the scintillator has been measured for alpha particles, deuterons, and protons. In the region 0.1 to 0.6 microseconds after its initial rise, the fluorescent decay can be accurately described by a simple exponential. The characteristic time for this exponential decay has been measured at several energies up to 28.7 MeV for a particles and 7.2 MeV for protons. We have found a linear relationship between this decay time and the logarithm of the particle energy, τ = k ln E + τo, where k and τo are constants which are characteristic of the type of stopping particle.

Womack, E. A.↗

NASA NTRS1973

Photoemission from CsI - Experiment.

Considerable attention in the investigation was given to the resolution maximization of details in the spectra. Very thin films were used in the measurements, which were conducted at 300 and 77 C with the aid of an improved photoemission apparatus. It was found that the principal features of the photoemission spectra from CsI cannot be explained on the basis of simple transitions from localized ionic states because such a model would predict a doublet instead of the triplet observed in the photoemission data.

Distefano, T. H.↗

NASA NTRS1975

The growth of deactivated layers on CsI(Na) scintillating crystals

An effective and sensitive measurement of the depth of a deactivated or dead layer can be obtained from the relative attenuation of the 22.162 KeV and 87.9 KeV X-rays emitted by Cd 109. The alpha-particles emitted by Am 241 are also useful in measuring dead layers less than 25 microns. The properties and temporal development of dead layers are discussed in detail. The rate of growth of a deal layer is closely related to the ambient humidity, and the damage to the crystal is irreversible by any known process. The dead layer can be minimized by polishing all crystal surfaces and by keeping the crystal in a vacuum or a dry atmosphere. Since a dead layer seriously inhibits the response of a crystal to X-rays of energies below approximately 20 keV, CsI(Na) detectors should not be used at these energies unless precautions are taken to ensure that no dead layer forms.

Goodman, N. B.↗

NASA NTRS1990

Remote Manipulator System (RMS)-based Controls-Structures Interaction (CSI) flight experiment feasibility study

The feasibility of an experiment which will provide an on-orbit validation of Controls-Structures Interaction (CSI) technology, was investigated. The experiment will demonstrate the on-orbit characterization and flexible-body control of large flexible structure dynamics using the shuttle Remote Manipulator System (RMS) with an attached payload as a test article. By utilizing existing hardware as well as establishing integration, operation and safety algorithms, techniques and procedures, the experiment will minimize the costs and risks of implementing a flight experiment. The experiment will also offer spin-off enhancement to both the Shuttle RMS (SRMS) and the Space Station RMS (SSRMS).

Demeo, Martha E.↗

NASA NTRS1989

NASA CSI suspension methods overview

New suspension techniques will be necesary for ground testing the flexible spacecraft anticipated in NASA's future space activity. The most complex spacecraft involve nonlinear maneuvering (i.e., large angle slewing) with articulating substructures such as remote manipulating systems. The NASA control-structure interaction (CSI) ground test method team has begun researching and developing methodology to suspend the future class of spacecraft. This overview describes the work completed thus far. The research objective and technical approach will be presented first. Second, will be a suspension device overview followed by an assessment of existing hardware. Two different mechanical zero-spring-rate mechanisms will be compared for optimal performance. Next, will be a description of how existing hardware can be evolved to meet more general suspension requirements. A comparison of suspending articulating structures overhead vs underneath will follow. After a few experimental results from the zero-spring-rate mechanism/air suspension cart will be concluding remarks and future work.

Woodard, Stanley E.↗

NASA NTRS1989

CSI technology validation on an LSS ground experiment facility

The test bed developed at JPL for experimental evaluation of new technologies for the control of large flexible space structures is described. The experiment consists of a flexible spacecraft dynamic simulator, sensors, actuators, a microcomputer, and an advanced programming environment. The test bed has been operational for over a year, and thus far nine experiments were completed or are currently in progress. Several of these experiments were reported at the 1987 CSI conference, and several recent ones are documented in this paper, including high order adaptive control, non-parametric system identification, and mu-synthesis robust control. An aggressive program of experiments is planned for the forseeable future.

Wang, S. J.↗

NASA NTRS1989

Algorithmic considerations of integrated design for CSI on a hypercube architecture

An approach is presented to the integrated design problem for actively controlled large, flexible mechanical systems for which Control Structure Interaction (CSI) problems are of concern. The two coupled design problems were identified as the optimal Structural Design problem the optimal Controller Design problem. These two problems can be addressed within a decision making loop that would consider each separately, and then sequentially analyze the effects of one on the other. Embedded in such a loop would be the simulation and coordination tasks as part of the decision tools required in a total (software) package. All of the above are compute-intensive tasks. In any such task, possible decompositions and gains due to the inherent parallelism have to be exploited. The problems under consideration, as applied to large flexible mechanical structures, are particularly suited to be mapped onto multicomputer systems in a hypercube topology.

Oezguener, UE.↗

NASA NTRS1990

High-pressure phase transition and equation of state of CsI

Stuructural properties of CsI at high pressure have been investigated by the use of synchrotron X-ray-diffraction techniques with the diamond-anvil cell at 300 K. The results indicate that the material undergoes a continuous distortion from B2 to an hcp-like phase, which is stable to at least 302 GPa. The intermediate orthorhombic phase is geometrically different from previous assignments and about 10 percent denser. With the new structure, the p-V results of static pressure experiments, shock-wave studies, and theoretical calculations are now in good agreement.

Mao, H. K.↗

NASA NTRS1991

Experimental demonstration of a classical approach for flexible space structure control: NASA CSI testbeds

The results of active control experiments performed for the Mini-Mast truss structure are presented. The primary research objectives were: (1) to develop active structural control concepts and/or techniques; (2) to verify the concept of robust non-minimum-phase compensation for a certain class of non-colocated structural control problems through ground experiments; (3) to verify a 'dipole' concept for persistent disturbance rejection control of flexible structures; and (4) to identify CSI (Control Structure Interaction) issues and areas of emphasis for the next generation of large flexible spacecraft. The classical SISO (Single Input and Single Output) control design approach was employed.

Bond, Wie↗