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All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Dark Energy Survey Year 3 results: galaxy sample for BAO measurement

Here, we present and validate the galaxy sample used for the analysis of the baryon acoustic oscillation (BAO) signal in the Dark Energy Survey (DES) Y3 data. The definition is based on a colour and redshift-dependent magnitude cut optimized to select galaxies at redshifts higher than 0.5, while ensuring a high-quality determination. The sample covers ~ 4100 square degrees to a depth of i = 22.3 (AB) at 10σ. It contains 7,031,993 galaxies in the redshift range from z = 0.6 to 1.1, with a mean effective redshift of 0.835. Redshifts are estimated with the machine learning algorithm DNF, and are validated using the VIPERS PDR2 sample. We find a mean redshift bias of z bias ~ 0.01 and a mean uncertainty, in units of 1 + z, of σ 68 ~ 0.03$. We evaluate the galaxy population of the sample, showing it is mostly built upon Elliptical to Sbc types. Furthermore, we find a low level of stellar contamination of ≲ 4 %. We present the method used to mitigate the effect of spurious clustering coming from observing conditions and other large-scale systematics. We apply it to the BAO sample and calculate weights that are used to get a robust estimate of the galaxy clustering signal. This paper is one of a series dedicated to the analysis of the BAO signal in DES Y3. In the companion papers, we present the galaxy mock catalogues used to calibrate the analysis and the angular diameter distance constraints obtained through the fitting to the BAO scale.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2022

Dark Energy Survey Year 3 results: Cosmology with moments of weak lensing mass maps

We present a cosmological analysis using the second and third moments of the weak lensing mass (convergence) maps from the first three years of data (Y3) data of the Dark Energy Survey. The survey spans an effective area of 4139 square degrees and uses the images of over 100 million galaxies to reconstruct the convergence field. The second moment of the convergence as a function of smoothing scale contains information similar to standard shear 2-point statistics. The third moment, or the skewness, contains additional non-Gaussian information. The data is analyzed in the context of the Λ CDM model, varying five cosmological parameters and 19 nuisance parameters modeling astrophysical and measurement systematics. Our modeling of the observables is completely analytical, and has been tested with simulations in our previous methodology study. We obtain a 1.7% measurement of the amplitude of fluctuations parameter S 8 ≡ σ 8 ( Ω m / 0.3 ) 0.5 = 0.784 ± 0.013 . The measurements are shown to be internally consistent across redshift bins, angular scales, and between second and third moments. In particular, the measured third moment is consistent with the expectation of gravitational clustering under the Λ CDM model. The addition of the third moment improves the constraints on S 8 and Ω m by ∼ 15 % and ∼ 25 % compared to an analysis that only uses second moments. We compare our results with Planck constraints from the cosmic microwave background, finding a 2.2 – 2.8 σ tension in the full parameter space, depending on the combination of moments considered. The third moment, independently, is in 2.8 σ tension with Planck, and thus provides a cross-check on the analyses of 2-point correlations.

79 ASTRONOMY AND ASTROPHYSICS↗
NASA NTRS2020

The Atacama Cosmology Telescope: arcminute-resolution maps of 18,000 square degrees of the microwave sky from ACT 2008-2018 data combined with Planck

This paper presents a maximum-likelihood algorithm for combining sky maps with disparate sky coverage, angular resolution and spatially varying anisotropic noise into a single map of the sky. We use this to merge hundreds of individual maps covering the 2008–2018 ACT observing seasons, resulting in by far the deepest ACT maps released so far. We also combine the maps with the full Planck maps, resulting in maps that have the best features of both Planck and ACT: Planck’s nearly white noise on intermediate and large angular scales and ACT’s high-resolution and sensitivity on small angular scales. The maps cover over 18 000 square degrees, nearly half the full sky, at 100, 150 and 220 GHz. They reveal 4 000 optically-confirmed clusters through the Sunyaev Zel’dovich effect (SZ) and 18 500 point source candidates at > 5σ, the largest single collection of SZ clusters and millimeter wave sources to date. The multi-frequency maps provide millimeter images of nearby galaxies and individual Milky Way nebulae, and even clear detections of several nearby stars. Other anticipated uses of these maps include, for example, thermal SZ and kinematic SZ cluster stacking, CMB cluster lensing and galactic dust science. The method itself has negligible bias. However, due to the preliminary nature of some of the component data sets, we caution that these maps should not be used for precision cosmological analysis. The maps are part of ACT DR5, and will be made available on LAMBDA no later than three months after the journal publication of this article, along with an interactive sky atlas.

Sigurd Naess↗
DOE OSTI2020

The Atacama Cosmology Telescope: arcminute-resolution maps of 18 000 square degrees of the microwave sky from ACT 2008–2018 data combined with Planck

This paper presents a maximum-likelihood algorithm for combining sky maps with disparate sky coverage, angular resolution and spatially varying anisotropic noise into a single map of the sky. We use this to merge hundreds of individual maps covering the 2008–2018 ACT observing seasons, resulting in by far the deepest ACT maps released so far. We also combine the maps with the full Planck maps, resulting in maps that have the best features of both Planck and ACT: Planck’s nearly white noise on intermediate and large angular scales and ACT’s high-resolution and sensitivity on small angular scales. The maps cover over 18 000 square degrees, nearly half the full sky, at 100, 150 and 220 GHz. Furthermore, they reveal 4 000 optically-confirmed clusters through the Sunyaev Zel’dovich effect (SZ) and 18 500 point source candidates at > 5σ, the largest single collection of SZ clusters and millimeter wave sources to date. The multi-frequency maps provide millimeter images of nearby galaxies and individual Milky Way nebulae, and even clear detections of several nearby stars. Other anticipated uses of these maps include, for example, thermal SZ and kinematic SZ cluster stacking, CMB cluster lensing and galactic dust science. The method itself has negligible bias. However, due to the preliminary nature of some of the component data sets, we caution that these maps should not be used for precision cosmological analysis. The maps are part of ACT DR5, and will be made available on LAMBDA no later than three months after the journal publication of this article, along with an interactive sky atlas.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2022

The Dark Energy Survey Bright Arcs Survey: Candidate Strongly Lensed Galaxy Systems from the Dark Energy Survey 5000 Square Degree Footprint

We report the combined results of eight searches for strong gravitational lens systems in the full 5000 square degrees of Dark Energy Survey (DES) observations. The observations accumulated by the end of the third observing season fully covered the DES footprint in five filters (grizY), with an i-band limiting magnitude (at 10σ) of 23.44. In four searches, a list of potential candidates was identified using a color and magnitude selection from the object catalogs created from the first three observing seasons. Three other searches were conducted at the locations of previously identified galaxy clusters. Cutout images of potential candidates were then visually scanned using an object viewer. An additional set of candidates came from a data-quality check of a subset of the color–coadd tiles created from the full DES six-season data set. A short list of the most promising strong-lens candidates was then numerically ranked according to whether or not we judged them to be bona fide strong gravitational lens systems. These searches discovered a diverse set of 247 strong-lens candidate systems, of which 81 are identified for the first time. We provide the coordinates, magnitudes, and photometric properties of the lens and source objects, and an estimate of the Einstein radius for 81 new systems and 166 previously reported systems. This catalog will be of use for selecting interesting systems for detailed follow up, studies of galaxy cluster and group mass profiles, as well as a training/validation set for automated strong-lens searches.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2020

Materials Data on PtS2NO9 by Materials Project

(PtS2O9)2N2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two ammonia molecules and one PtS2O9 cluster. In the PtS2O9 cluster, Pt5+ is bonded to five O2- atoms to form PtO5 square pyramids that share corners with four SO4 tetrahedra. There are a spread of Pt–O bond distances ranging from 1.98–2.02 Å. There are two inequivalent S6+ sites. In the first S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two equivalent PtO5 square pyramids. There are a spread of S–O bond distances ranging from 1.44–1.58 Å. In the second S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two equivalent PtO5 square pyramids. There are a spread of S–O bond distances ranging from 1.44–1.58 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Pt5+ and one S6+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Pt5+ and one S6+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to one Pt5+ and one S6+ atom. In the eighth O2- site, O2- is bonded in a bent 120 degrees geometry to one Pt5+ and one S6+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one Pt5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Galaxy Clusters Discovered via the Thermal Sunyaev-Zel’dovich Effect in the 500-square-degree SPTpol Survey

We present a catalog of 689 galaxy cluster candidates detected at significance ξ > 4 via their thermal Sunyaev-Zel’dovich (SZ) effect signature in 95 and 150 GHz data from the 500-square-degree SPTpol survey. We use optical and infrared data from the Dark Energy Camera and the Wide-field Infrared Survey Explorer (WISE) and Spitzer satellites, to confirm 544 of these candidates as clusters with ~ 94% purity. The sample has an approximately redshift-independent mass threshold at redshift z > 0.25. The confirmed sample spans 1.5 × 10 14 < M 500 c < 9 × 10 14 M ⊙ /h 70 and 0.03 < z ≲ 1.6 in mass and redshift, respectively, with a median mass of 2.5×10 14 M ⊙ /h 70 and median redshift z = 0.7; 21% of the confirmed clusters are at z > 1. We use external radio data from the Sydney University Molonglo Sky Survey (SUMSS) to estimate contamination to the SZ signal from synchrotron sources. The contamination reduces the recovered ξ by a median value of 0.032, or ~ 0.8% of the ξ = 4 threshold value, and ~ 7% of candidates have a predicted contamination greater than Δξ = 1. With the exception of a small number of systems (< 1%), an analysis of clusters detected in single-frequency 95 and 150 GHz data shows no significant contamination of the SZ signal by emission from dusty or synchrotron sources. This cluster sample, representing the deepest SZ-selected cluster sample to date, will be a key component in upcoming astrophysical and cosmological analyses of clusters. In addition to the cluster catalog, we also release the millimeter-wave maps and associated data products used to produce this sample. These maps have depths of 5.3 (11.7) µK CMB -arcmin at 150 (95) GHz and an effective angular resolution of 1. '2 (1. '7). The SPTpol products are available at https:// pole.uchicago.edu/public/data/sptpol_500d_clusters/index.html, and the NASA LAMBDA website. An interactive sky server with the SPTpol maps and Dark Energy Survey data release 2 images is also available at NCSA https://skyviewer.ncsa.illinois.edu.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2021

WALLABY pre-pilot survey: two dark clouds in the vicinity of NGC 1395

ABSTRACT We present the Australian Square Kilometre Array Pathfinder (ASKAP) WALLABY pre-pilot observations of two ‘dark’ H i sources (with H i masses of a few times 108 $\rm {M}_\odot$ and no known stellar counterpart) that reside within 363 kpc of NGC 1395, the most massive early-type galaxy in the Eridanus group of galaxies. We investigate whether these ‘dark’ H i sources have resulted from past tidal interactions or whether they are an extreme class of low surface brightness galaxies. Our results suggest that both scenarios are possible, and not mutually exclusive. The two ‘dark’ H i sources are compact, reside in relative isolation, and are more than 159 kpc away from their nearest H i-rich galaxy neighbour. Regardless of origin, the H i sizes and masses of both ‘dark’ H i sources are consistent with the H i size–mass relationship that is found in nearby low-mass galaxies, supporting the possibility that these H i sources are an extreme class of low surface brightness galaxies. We identified three analogues of candidate primordial ‘dark’ H i galaxies within the TNG100 cosmological, hydrodynamic simulation. All three model analogues are dark matter dominated, have assembled most of their mass 12–13 Gyr ago, and have not experienced much evolution until cluster infall 1–2 Gyr ago. Our WALLABY pre-pilot science results suggest that the upcoming large-area H i surveys will have a significant impact on our understanding of low surface brightness galaxies and the physical processes that shape them.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2020

Materials Data on NiH20Se2(NO7)2 by Materials Project

NiH6(SeO6)2(H2)3(NH3OH)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight hydrogen molecules, four water nitrogen molecules, and two NiH6(SeO6)2 clusters. In each NiH6(SeO6)2 cluster, Ni2+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.84 Å) and two longer (2.01 Å) Ni–O bond length. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.03 Å) and one longer (1.60 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. Se2- is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.65–1.85 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one O2- atom. The O–O bond length is 1.24 Å. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Ni2+ and two H1+ atoms. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Ni2+ and one O2- atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Se2- atom. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to one H1+ and one Se2- atom. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to one H1+ and one Se2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2026

The SPT-deep Cluster Catalog: Sunyaev–Zel’dovich Selected Clusters from Combined SPT-3G and SPTpol Measurements over 100 Square Degrees

We present a catalog of 500 galaxy cluster candidates in the SPT-Deep field: a 100 deg$^{2}$ field that combines data from the SPT-3G and SPTpol surveys to reach noise levels of 3.0, 2.2, and 9.0 μK-arcmin at 95, 150, and 220 GHz, respectively. Candidates are selected via the thermal Sunyaev–Zel’dovich (SZ) effect with a minimum significance of ξ = 4.0, resulting in a catalog of purity ∼89%. Optical data from the Dark Energy Survey and infrared data from the Spitzer Space Telescope are used to confirm 442 cluster candidates. The clusters span 0.12 < z ≲ 1.8 and 1.0 × 10$^{14}$M$_{⊙}$/h$_{70}$ < M$_{500c}$ < 8.7 × 10$^{14}$M$_{⊙}$/h$_{70}$. The sample’s median redshift is 0.74, and the median mass is 1.7 × 10$^{14}$M$_{⊙}$/h$_{70}$; these are the lowest median mass and highest median redshift of any SZ-selected sample to date. We assess the effect of infrared emission from cluster member galaxies on cluster selection by performing a joint fit to the infrared dust and tSZ signals by combining measurements from SPT and overlapping submillimeter data from Herschel/SPIRE. We find that at high redshift (z > 1), the tSZ signal is reduced by $17.9_{−3.2}^{+3.8}$%$(3.8_{−0.7}^{+0.9}$%$)$ at 150 GHz (95 GHz) due to dust contamination. We repeat our cluster finding method on dust-nulled SPT maps and find the resulting catalog is consistent with the nominal SPT-Deep catalog, suggesting dust contamination does not significantly impact the SPT-Deep selection function; we attribute this lack of bias to the inclusion of the SPT 220 GHz band.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2024

Dark Energy Survey: A 2.1% measurement of the angular baryonic acoustic oscillation scale at redshift z eff = 0.85 from the final dataset

Here, we present the angular diameter distance measurement obtained with the baryonic acoustic oscillation (BAO) feature from galaxy clustering in the completed Dark Energy Survey, consisting of six years (Y6) of observations. We use the Y6 BAO galaxy sample, optimized for BAO science in the redshift range 0.6 < z <1.2, with an effective redshift at z eff = 0.85 and split into six tomographic bins. The sample has nearly 16 million galaxies over 4,273 square degrees. Our consensus measurement constrains the ratio of the angular distance to sound horizon scale to D M ⁡(z eff )/r d = 19.51 ± 0.41 (at 68.3% confidence interval), resulting from comparing the BAO position in our data to that predicted by planck Λ⁢CDM via the BAO shift parameter α =(D M /r d )/(D M /r d ) PLANCK . To achieve this, the BAO shift is measured with three different methods, angular correlation function (ACF), angular power spectrum (APS), and projected correlation function (PCF), obtaining α = 0.952 ± 0.023, 0.962 ± 0.022, and 0.955 ± 0.020, respectively, which we combine to α = 0.957 ± 0.020, including systematic errors. When compared with the Λ⁢CDM model that best fits planck data, this measurement is found to be 4.3% and 2.1⁢σ below the angular BAO scale predicted. To date, it represents the most precise angular BAO measurement at z > 0.75 from any survey and the most precise measurement at any redshift from photometric surveys. The analysis was performed blinded to the BAO position, and it is shown to be robust against analysis choices, data removal, redshift calibrations, and observational systematics.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2023

Metal-insulator transition and magnetism of SU(3) fermions in the square lattice

We study the SU(3) symmetric Fermi-Hubbard model (FHM) in the square lattice at 1/3-filling using numerically exact determinant quantum Monte Carlo and numerical linked-cluster expansion techniques. We present the different regimes of the model in the T–U plane, which are characterized by local and short-range correlations, and capture signatures of the metal-insulator transition and magnetic crossovers. These signatures are detected as the temperature scales characterizing the rise of the compressibility, and an interaction-dependent change in the sign of the diagonal spin-spin correlation function. The analysis of the compressibility estimates the location of the metal-insulator quantum critical point at U c /t ~ 6, and provides a temperature scale for observing Mott physics at finite T. Furthermore, from the analysis of the spin-spin correlation function we observe that for U/t ≳ 6 and T ~ J = 4⁢t 2 /U there is a development of a short-range two-sublattice (2SL) antiferromagnetic structure, as well as an emerging three-sublattice (3SL) antiferromagnetic structure as the temperature is lowered below T/J ≲ 0.57. This crossover from 2SL to 3SL magnetic ordering agrees with Heisenberg limit predictions, and has observable effects on the density of on-site pairs. Finally, we describe how the features of the regimes in the T–U plane can be explored with alkaline-earth-like atoms in optical lattices with currently achieved experimental techniques and temperatures. Furthermore, the results discussed in this paper provide a starting point for the exploration of the SU(3) FHM upon doping.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2020

Materials Data on Pt3S3NO14 by Materials Project

(Pt3S3O14)2N2 crystallizes in the trigonal R-3 space group. The structure is zero-dimensional and consists of twelve ammonia molecules and three Pt3S3O14 clusters. In each Pt3S3O14 cluster, there are two inequivalent Pt+4.33+ sites. In the first Pt+4.33+ site, Pt+4.33+ is bonded to five O2- atoms to form PtO5 square pyramids that share corners with four PtO5 square pyramids and corners with three SO4 tetrahedra. There are a spread of Pt–O bond distances ranging from 2.02–2.18 Å. In the second Pt+4.33+ site, Pt+4.33+ is bonded to five O2- atoms to form PtO5 square pyramids that share corners with four PtO5 square pyramids and corners with three SO4 tetrahedra. There are a spread of Pt–O bond distances ranging from 2.02–2.17 Å. There are two inequivalent S+3.33+ sites. In the first S+3.33+ site, S+3.33+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three PtO5 square pyramids. There are a spread of S–O bond distances ranging from 1.42–1.54 Å. In the second S+3.33+ site, S+3.33+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three PtO5 square pyramids. There are a spread of S–O bond distances ranging from 1.43–1.54 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Pt+4.33+ and one S+3.33+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Pt+4.33+ and one S+3.33+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Pt+4.33+ and one S+3.33+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one S+3.33+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one Pt+4.33+ and one S+3.33+ atom. In the sixth O2- site, O2- is bonded in a trigonal planar geometry to three equivalent Pt+4.33+ atoms. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to one Pt+4.33+ and one S+3.33+ atom. In the eighth O2- site, O2- is bonded in a trigonal planar geometry to three Pt+4.33+ atoms. In the ninth O2- site, O2- is bonded in a single-bond geometry to one S+3.33+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Pt+4.33+ and one S+3.33+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Rapidity distributions of Z = 1 isotopes and the nuclear symmetry energy from Sn+Sn collisions with radioactive beams at 270 MeV/nucleon

The rapidity distributions of hydrogen isotopes emitted from central collisions of neutron-rich 132 Sn+ 124 Sn and neutron-deficient 108 Sn+ 112 Sn systems at 270 MeV/nucleon were investigated at RIKEN-RIBF. The data are compared with antisymmetrized molecular dynamics (AMD) calculations and the rapidity distributions can be reproduced after adjusting the in-medium nucleon-nucleon cross sections. The double ratios between the two reaction systems taken for the relative yields of deuteron to proton (d/p) and triton to proton (t/p) are further examined in the midrapidity domain, where the adjustments in the AMD calculations do not affect much on them. The d/p and t/p double ratios at midrapidity agree well with the ratio of the system neutron numbers and its squared value, respectively, and the rapidity dependence of these double ratios is consistent with a picture of partial mixing of colliding nuclei. By comparing with the AMD model which shows a strong symmetry energy dependence of the t/p double ratio, the experimental result in the midrapidity domain favors the calculation with a symmetry-energy slope parameter around L = 46 MeV rather than L = 108 MeV.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
NASA NTRS2005

Research on Spectroscopy, Opacity, and Atmospheres

I propose to continue providing observers with basic data for interpreting spectra from stars, novas, supernovas, clusters, and galaxies. These data will include allowed and forbidden line lists, both laboratory and computed, for the first five to ten ions of all atoms and for all relevant diatomic molecules. I will eventually expand to all ions of the first thirty elements to treat far UV and X-ray spectra, and for envelope opacities. I also include triatomic molecules provided by other researchers. I have also made CDs with Partridge and Schwenke's water data for work on UV stars. The line data also serve as input to my model atmosphere and synthesis programs that generate energy distributions, photometry, limb darkening, and spectra that can be used for planning observations and for fitting observed spectra. The spectrum synthesis programs produce detailed plots with the lines identified. Grids of stellar spectra can be used for radial velocity-, rotation-, or abundance templates and for population synthesis. I am fitting spectra of bright stars to test the data and to produce atlases to guide observers. For each star the whole spectrum is computed from the UV to the far IR. The line data, opacities, models, spectra, and programs are freely distributed on CDs and on my Web site and represent a unique resource for many NASA programs. I am now in full production of new line lists for atoms. I am computing all ions of all elements from H to Zn and the first 5 ions of all the heavier elements, about 800 ions. For each ion I treat as many as 61 even and 61 odd configurations, computing all energy levels and eigenvectors. The Hamiltonian is determined from a scaled-Hartree-Fock starting guess by least squares fitting the observed energy levels. The average energy of each configuration is used in computing scaled-Thomas-Fermi-Dirac wavefunctions for each configuration which in turn are used to compute allowed and forbidden transition integrals. These are multiplied into the LS allowed and forbidden transition arrays. The transition arrays are transformed to the observed coupling to yield the allowed and forbidden line lists. Results are put on the web as they are finished. Provided I get funding,there will be more than 500 million lines. I will then compare ion by ion, to all the laboratory and computed data in the literature and make up a working line list for spectrum synthesis and opacity calculations with the best available data. As the laboratory spectrum analyses are improved, I will redo the calculations with the new energy levels. My original plan when I started the new calculations was to run through all the atoms using my old Cray programs from the 1980's that were limited to 1100 x 1100 arrays in the Hamiltonian for each J. Then I would go back and rerun the more complicated cases with 3000 x 3000 arrays so that I could include many more configurations and more configuration interactions. At present I am limited to 61 even and 61 odd configurations and I try to include everything up through n = 9. The current program runs on Alpha workstations. I decided to test the big program on Fe I and Fe II to see whether there was any great difference in the low configurations compared to those from the Cray program. Besides increasing the number of E1 lines by a factor of 6 to 7.7 million, there was an unexpected result: the electric quadrupole transitions were 10 times stronger than before because the transition integrals are weighted by r(exp 2) ---they become very large for high n, and because there are numerous configuration interactions that mix the low and high configurations. As a check I was able to reproduce Carstang's (1962) lower results by running his three configurations with my program. Since my model atom is still only a subset of a real Fe II ion, the true quadrupole A values are probably larger than mine. The magnetic dipole lines are affected by the mixing but the overall scale does not change. Because of this scovery I decided that there was no point in computing the small array cases. I have been running with as many configurations as I can and with thousands of parameters in the Hamiltonian. The computer runs take much longer to set up and produce than I had expected. I have concentrated on redoing the low iron group spectra, especially to get data for supernova modelers. I have done only Ca I -- Zn I, Ca II -- Zn II, CU I -- Cu XXIX, Zn I - Zn XXX, for practice at high stages of ionization, C I, C II, S I, and CL I and Ag I for people who were working on the laboratory spectra. Check my web site kurucz.harvard.edu for current additions. My latest calculations have been for carbon I and sulphur I, and silicon I is under way using the same elaborate approach as for C I, which took many months to do. These line lists greatly increase the number of lines in the ultraviolet, in the visible, and especially in the infrared. They will increase the opacity in A, F, and G stars. They will account for many unidentified lines in the sun.

Kurucz, Robert L.↗
DOE OSTI2020

Materials Data on Mo6H10N2Cl14O by Materials Project

(Mo3Cl7)2(NH4)2H2O crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of four ammonium molecules, two water molecules, and two Mo3Cl7 clusters. In each Mo3Cl7 cluster, there are six inequivalent Mo2+ sites. In the first Mo2+ site, Mo2+ is bonded in a distorted see-saw-like geometry to four Cl1- atoms. There are a spread of Mo–Cl bond distances ranging from 2.48–2.92 Å. In the second Mo2+ site, Mo2+ is bonded to five Cl1- atoms to form edge-sharing MoCl5 square pyramids. There are a spread of Mo–Cl bond distances ranging from 2.41–2.61 Å. In the third Mo2+ site, Mo2+ is bonded to five Cl1- atoms to form edge-sharing MoCl5 square pyramids. There are a spread of Mo–Cl bond distances ranging from 2.40–2.65 Å. In the fourth Mo2+ site, Mo2+ is bonded in a distorted see-saw-like geometry to four Cl1- atoms. There are a spread of Mo–Cl bond distances ranging from 2.49–2.95 Å. In the fifth Mo2+ site, Mo2+ is bonded in a 3-coordinate geometry to three Cl1- atoms. There are one shorter (2.46 Å) and two longer (2.55 Å) Mo–Cl bond lengths. In the sixth Mo2+ site, Mo2+ is bonded in a 3-coordinate geometry to three Cl1- atoms. There are a spread of Mo–Cl bond distances ranging from 2.45–2.58 Å. There are fourteen inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 1-coordinate geometry to three Mo2+ atoms. In the second Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two Mo2+ atoms. In the third Cl1- site, Cl1- is bonded in an L-shaped geometry to two Mo2+ atoms. In the fourth Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two Mo2+ atoms. In the fifth Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two Mo2+ atoms. In the sixth Cl1- site, Cl1- is bonded in an L-shaped geometry to two Mo2+ atoms. In the seventh Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Mo2+ atoms. In the eighth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to three Mo2+ atoms. In the ninth Cl1- site, Cl1- is bonded in a single-bond geometry to one Mo2+ atom. In the tenth Cl1- site, Cl1- is bonded in a single-bond geometry to one Mo2+ atom. In the eleventh Cl1- site, Cl1- is bonded in a single-bond geometry to one Mo2+ atom. In the twelfth Cl1- site, Cl1- is bonded in a single-bond geometry to one Mo2+ atom. In the thirteenth Cl1- site, Cl1- is bonded in a single-bond geometry to one Mo2+ atom. In the fourteenth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Mo2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mo6H10N2Cl14O by Materials Project

(Mo3Cl7)2(NH4)2H2O crystallizes in the monoclinic Cc space group. The structure is zero-dimensional and consists of eight ammonium molecules, four water molecules, and four Mo3Cl7 clusters. In each Mo3Cl7 cluster, there are six inequivalent Mo2+ sites. In the first Mo2+ site, Mo2+ is bonded in a distorted T-shaped geometry to three Cl1- atoms. There are one shorter (2.47 Å) and two longer (2.54 Å) Mo–Cl bond lengths. In the second Mo2+ site, Mo2+ is bonded in a 3-coordinate geometry to five Cl1- atoms. There are a spread of Mo–Cl bond distances ranging from 2.44–3.11 Å. In the third Mo2+ site, Mo2+ is bonded in a square pyramidal geometry to five Cl1- atoms. There are a spread of Mo–Cl bond distances ranging from 2.41–2.53 Å. In the fourth Mo2+ site, Mo2+ is bonded in a square pyramidal geometry to five Cl1- atoms. There are a spread of Mo–Cl bond distances ranging from 2.45–2.54 Å. In the fifth Mo2+ site, Mo2+ is bonded in a 3-coordinate geometry to three Cl1- atoms. There are a spread of Mo–Cl bond distances ranging from 2.46–2.55 Å. In the sixth Mo2+ site, Mo2+ is bonded in a distorted T-shaped geometry to three Cl1- atoms. There are one shorter (2.44 Å) and two longer (2.55 Å) Mo–Cl bond lengths. There are fourteen inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Mo2+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Mo2+ atom. In the third Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two Mo2+ atoms. In the fourth Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to three Mo2+ atoms. In the fifth Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two Mo2+ atoms. In the sixth Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to three Mo2+ atoms. In the seventh Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two Mo2+ atoms. In the eighth Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two Mo2+ atoms. In the ninth Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two Mo2+ atoms. In the tenth Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two Mo2+ atoms. In the eleventh Cl1- site, Cl1- is bonded in a single-bond geometry to one Mo2+ atom. In the twelfth Cl1- site, Cl1- is bonded in a single-bond geometry to one Mo2+ atom. In the thirteenth Cl1- site, Cl1- is bonded in a single-bond geometry to one Mo2+ atom. In the fourteenth Cl1- site, Cl1- is bonded in a single-bond geometry to one Mo2+ atom.

36 MATERIALS SCIENCE↗
NASA NTRS2013

Concurrent Supermassive Black Hole and Galazy Growth: Linking Environment and Nuclear Activity in Zeta Equals 2.23 H Alpha Emitters

We present results from an approximately equal 100 ks Chandra observation of the 2QZ Cluster 1004+00 structure at z = 2.23 (hereafter 2QZ Clus). 2QZ Clus was originally identified as an overdensity of four optically-selected QSOs at z = 2.23 within a 15 × 15 arcmin square region. Narrow-band imaging in the near-IR (within the K band) revealed that the structure contains an additional overdensity of 22 z = 2.23 H alpha-emitting galaxies (HAEs), resulting in 23 unique z = 2.23 HAEs/QSOs (22 within the Chandra field of view). Our Chandra observations reveal that three HAEs in addition to the four QSOs harbor powerfully accreting supermassive black holes (SMBHs), with 2-10 keV luminosities of approximately equal (8-60) × 10(exp 43) erg s(exp−1) and X-ray spectral slopes consistent with unobscured active galactic nucleus (AGN). Using a large comparison sample of 210 z = 2.23 HAEs in the Chandra-COSMOS field (C-COSMOS), we find suggestive evidence that the AGN fraction increases with local HAE galaxy density. The 2QZ Clus HAEs reside in a moderately overdense environment (a factor of approximately equal 2 times over the field), and after excluding optically-selected QSOs, we find that the AGN fraction is a factor of approximately equal 3.5(+3.8/ −2.2) times higher than C-COSMOS HAEs in similar environments. Using stacking analyses of the Chandra data and Herschel SPIRE observations at 250micrometers, we respectively estimate mean SMBH accretion rates ( M(BH)) and star formation rates (SFRs) for the 2QZ Clus and C-COSMOS samples. We find that the mean 2QZ Clus HAE stacked X-ray luminosity is QSO-like (L(2−10 keV) approximately equal [6-10] × 10(exp 43) erg s(exp −1)), and the implied M(BH)/SFR approximately equal (1.6-3.2) × 10(exp −3) is broadly consistent with the local M(BH)/Stellar Mass relation and z approximately equal 2 X-ray selected AGN. In contrast, the C-COSMOS HAEs are on average an order of magnitude less X-ray luminous and have M(BH)/SFR approximately equal (0.2-0.4) × 10(exp −3), somewhat lower than the local MBH/M relation, but comparable to that found for z approximately equal 1-2 star-forming galaxies with similar mean X-ray luminosities. We estimate that a periodic QSO phase with duty cycle approximately 2%-8% would be sufficient to bring star-forming galaxies onto the local M(BH)/Stellar Mass relation. This duty cycle is broadly consistent with the observed C-COSMOS HAE AGN fraction (Approximately equal 0.4%-2.3%) for powerful AGN with LX approximately greater than 10(exp 44) erg s(exp −1). Future observations of 2QZ Clus will be needed to identify key factors responsible for driving the mutual growth of the SMBHs and galaxies.

Lehmer, B. D.↗