Results for “V3(OF)4” — Page 14

DOE OSTI2020

Possible octupole deformation of 208 Pb and the ultracentral v 2 to v 3 puzzle

Recent measurements have established the sensitivity of ultracentral heavy-ion collisions to the deformation parameters of nonspherical nuclei. In the case of 129 Xe collisions, a quadrupole deformation of the nuclear profile led to an enhancement of elliptic flow in the most central collisions. In 208 Pb collisions a discrepancy exists in similar centralities, where either elliptic flow is overpredicted or triangular flow is underpredicted by hydrodynamic models; this is known as the v 2 -to-v 3 puzzle in ultracentral collisions. Motivated by low-energy nuclear structure calculations, we consider the possibility that 208Pb nuclei could have a pear-shape deformation (octupole), which has the effect of increasing triangular flow in central PbPb collisions. Using the recent data from ALICE and ATLAS, we reexamine the v 2 -to-v 3 puzzle in ultracentral collisions, including new constraints from recent measurements of the triangular cumulant ratio v 3 {4}/v 3 {2} and comparing two different hydrodynamic models. We find that while an octupole deformation would slightly improve the ratio between v 2 and v 3 , it is at the expense of a significantly worse triangular flow cumulant ratio. In fact, the latter observable prefers no octupole deformation, with β 3 ≲ 0.0375 for 208 Pb, and is therefore consistent with the expectation for a doubly-magic nucleus even at top collider energies. Furthermore, the v 2 -to-v 3 puzzle remains a challenge for hydrodynamic models.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2020

Materials Data on MgV2O4 by Materials Project

MgV2O4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 pentagonal pyramids that share corners with six VO6 octahedra, edges with six VO6 octahedra, and edges with two equivalent MgO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 4–15°. There are a spread of Mg–O bond distances ranging from 2.11–2.26 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 pentagonal pyramids that share corners with six VO6 octahedra, edges with six VO6 octahedra, and edges with two equivalent MgO6 pentagonal pyramids. The corner-sharing octahedra tilt angles range from 2–14°. There are a spread of Mg–O bond distances ranging from 2.14–2.24 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 pentagonal pyramids that share corners with twelve VO6 octahedra, edges with two equivalent MgO6 pentagonal pyramids, and faces with two VO6 octahedra. The corner-sharing octahedra tilt angles range from 45–52°. There are a spread of Mg–O bond distances ranging from 2.17–2.23 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 pentagonal pyramids that share corners with twelve VO6 octahedra, edges with two equivalent MgO6 pentagonal pyramids, and faces with two VO6 octahedra. The corner-sharing octahedra tilt angles range from 45–53°. There are a spread of Mg–O bond distances ranging from 2.17–2.23 Å. There are eight inequivalent V3+ sites. In the first V3+ site, V3+ is bonded to six O2- atoms to form VO6 octahedra that share corners with five MgO6 pentagonal pyramids, edges with six VO6 octahedra, an edgeedge with one MgO6 pentagonal pyramid, and a faceface with one MgO6 pentagonal pyramid. There are a spread of V–O bond distances ranging from 2.01–2.12 Å. In the second V3+ site, V3+ is bonded to six O2- atoms to form VO6 octahedra that share corners with five MgO6 pentagonal pyramids, edges with six VO6 octahedra, an edgeedge with one MgO6 pentagonal pyramid, and a faceface with one MgO6 pentagonal pyramid. There are a spread of V–O bond distances ranging from 2.01–2.12 Å. In the third V3+ site, V3+ is bonded to six O2- atoms to form VO6 octahedra that share corners with five MgO6 pentagonal pyramids, edges with six VO6 octahedra, an edgeedge with one MgO6 pentagonal pyramid, and a faceface with one MgO6 pentagonal pyramid. There are a spread of V–O bond distances ranging from 2.01–2.13 Å. In the fourth V3+ site, V3+ is bonded to six O2- atoms to form VO6 octahedra that share corners with five MgO6 pentagonal pyramids, edges with six VO6 octahedra, an edgeedge with one MgO6 pentagonal pyramid, and a faceface with one MgO6 pentagonal pyramid. There are a spread of V–O bond distances ranging from 2.01–2.12 Å. In the fifth V3+ site, V3+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four MgO6 pentagonal pyramids, edges with six VO6 octahedra, and edges with two MgO6 pentagonal pyramids. There are a spread of V–O bond distances ranging from 1.99–2.11 Å. In the sixth V3+ site, V3+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four MgO6 pentagonal pyramids, edges with six VO6 octahedra, and edges with two MgO6 pentagonal pyramids. There are a spread of V–O bond distances ranging from 2.00–2.11 Å. In the seventh V3+ site, V3+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four MgO6 pentagonal pyramids, edges with six VO6 octahedra, and edges with two MgO6 pentagonal pyramids. There are a spread of V–O bond distances ranging from 2.00–2.11 Å. In the eighth V3+ site, V3+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four MgO6 pentagonal pyramids, edges with six VO6 octahedra, and edges with two MgO6 pentagonal pyramids. There are a spread of V–O bond distances ranging from 1.99–2.11 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three V3+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three V3+ atoms. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three V3+ atoms. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three V3+ atoms. In the fifth O2- site, O2- is bonded to one Mg2+ and three V3+ atoms to form OMgV3 trigonal pyramids that share corners with four OMg2V3 trigonal bipyramids, corners with three OMgV3 trigonal pyramids, and edges with four OMg2V3 trigonal bipyramids. In the sixth O2- site, O2- is bonded to one Mg2+ and three V3+ atoms to form OMgV3 trigonal pyramids that share corners with four OMg2V3 trigonal bipyramids, corners with three OMgV3 trigonal pyramids, and edges with four OMg2V3 trigonal bipyramids. In the seventh O2- site, O2- is bonded to one Mg2+ and three V3+ atoms to form OMgV3 trigonal pyramids that share corners with four OMg2V3 trigonal bipyramids, corners with three OMgV3 trigonal pyramids, and edges with four OMg2V3 trigonal bipyramids. In the eighth O2- site, O2- is bonded to one Mg2+ and three V3+ atoms to form OMgV3 trigonal pyramids that share corners with four OMg2V3 trigonal bipyramids, corners with three OMgV3 trigonal pyramids, and edges with four OMg2V3 trigonal bipyramids. In the ninth O2- site, O2- is bonded to two Mg2+ and three V3+ atoms to form OMg2V3 trigonal bipyramids that share corners with five OMg2V3 trigonal bipyramids, corners with two OMgV3 trigonal pyramids, edges with four OMg2V3 trigonal bipyramids, and edges with two OMgV3 trigonal pyramids. In the tenth O2- site, O2- is bonded to two Mg2+ and three V3+ atoms to form OMg2V3 trigonal bipyramids that share corners with five OMg2V3 trigonal bipyramids, corners with two OMgV3 trigonal pyramids, edges with four OMg2V3 trigonal bipyramids, and edges with two OMgV3 trigonal pyramids. In the eleventh O2- site, O2- is bonded to two Mg2+ and three V3+ atoms to form OMg2V3 trigonal bipyramids that share corners with five OMg2V3 trigonal bipyramids, corners with two OMgV3 trigonal pyramids, edges with four OMg2V3 trigonal bipyramids, and edges with two OMgV3 trigonal pyramids. In the twelfth O2- site, O2- is bonded to two Mg2+ and three V3+ atoms to form OMg2V3 trigonal bipyramids that share corners with five OMg2V3 trigonal bipyramids, corners with two OMgV3 trigonal pyramids, edges with four OMg2V3 trigonal bipyramids, and edges with two OMgV3 trigonal pyramids. In the thirteenth O2- site, O2- is bonded to two Mg2+ and three V3+ atoms to form OMg2V3 trigonal bipyramids that share corners with five OMg2V3 trigonal bipyramids, corners with two OMgV3 trigonal pyramids, edges with four OMg2V3 trigonal bipyramids, and edges with two OMgV3 trigonal pyramids. In the fourteenth O2- site, O2- is bonded to two Mg2+ and three V3+ atoms to form OMg2V3 trigonal bipyramids that share corners with five OMg2V3 trigonal bipyramids, corners with two OMgV3 trigonal pyramids, edges with four OMg2V3 trigonal bipyramids, and edges with two OMgV3 trigonal pyramids. In the fifteenth O2- site, O2- is bonded to two Mg2+ and three V3+ atoms to form OMg2V3 trigonal bipyramids that share corners with five OMg2V3 trigonal bipyramids, corners with two OMgV3 trigonal pyramids, edges with four OMg2V3 trigonal bipyramids, and edges with two OMgV3 trigonal pyramids. In the sixteenth O2- site, O2- is bonded to two Mg2+ and three V3+ atoms to form OMg2V3 trigonal bipyramids that share corners with five OMg2V3 trigonal bipyramids, corners with two OMgV3 trigonal pyramids, edges with four OMg2V3 trigonal bipyramids, and edges with two OMgV3 trigonal pyramids.

36 MATERIALS SCIENCE↗

DOE OSTI2022

ARM data-oriented metrics and diagnostics package for climate model evaluation (ARM-DIAGS-V3) version 3

A Python-based metrics and diagnostics package is currently being developed by the ARM Infrastructure Team at Lawrence Livermore National Laboratory to facilitate the use of long-term high frequency measurements from the ARM program in evaluating the regional climate simulation of clouds, radiation, precipitation, and aerosols. This metrics and diagnostics package computes climatological means of targeted climate model simulation and generates tables and plots for comparing the model simulation with ARM observational data. The CMIP model data sets are also included in the package to enable model inter-comparison as demonstrated in Zhang et al. (2018) and Zhang et al. (2020). The mean of the CMIP model can be served as a reference for individual models. Basic performance metrics are computed to measure the accuracy of mean state and variability of climate models. The evaluated physical quantities include cloud fraction, temperature, relative humidity, cloud liquid water path, total column water vapor, precipitation, sensible and latent heat fluxes, aerosol optical depth, and radiative fluxes, with plan to extend to more fields, such as the evaluation of model simulated aerosol physicochemical properties and cloud microphysics properties. Process-oriented diagnostics focusing on aerosol, cloud, and precipitation-related phenomena are also being developed for the evaluation and development of specific model physical parameterizations. In addition to the Southern Great Plains (SGP), North Slope of Alaska (NSA) and Tropical Western Pacific (TWP) atmospheric observatories in the ARMDIAGS version 2.0, the version 3.0 package have extended to the data collected at the ARM Eastern North Atlantic (ENA) atmospheric observatory and the Observation and Modeling of the Green Ocean Amazon (GOAMAZON) field campaign. The metrics and diagnostics package are currently built upon standard Python libraries and additional Python packages developed by DOE (CDAT). The ARM metrics and diagnostic package is available publicly with the hope that it can serve as an easy entry point for climate modelers to compare their models with ARM data. In this report, we first provide an overview of major metrics in section 2. The input data, which constitutes the core content of the metrics and diagnostics package, is summarized in section 3. A user's guide documenting the workflow/structure of the version 3.0 codes and including step-by-step instruction for running the package is described in section 4.

54 ENVIRONMENTAL SCIENCES↗