cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.48577/jpl.su3feb
title: CLMM: a LSST-DESC Cluster weak Lensing Mass Modeling library for cosmology

description: We present the v1.0 release of CLMM, an open source Python library for the estimation of the weak lensing massesof clusters of galaxies. CLMM is designed as a standalone toolkit of building blocks to enable end-to-end analysispipeline validation for upcoming cluster cosmology analyses such as the ones that will be performed by the LSST-DESC. Its purpose is to serve as a exible, easy-to-install and easy-to-use interface for both weak lensing simulatorsand observers and can be applied to real and mock data to study the systematics aecting weak lensing massreconstruction. At the core of CLMM are routines to model the weak lensing shear signal given the underlying massdistribution of galaxy clusters and a set of data operations to prepare the corresponding data vectors. The theoreticalpredictions rely on existing software, used as backends in the code, that have been thoroughly tested and cross-checked. Combined, theoretical predictions and data can be used to constrain the mass distribution of galaxy clustersas demonstrated in a suite of example Jupyter Notebooks shipped with the software and also available in the extensiveonline documentation.
DOI: 10.48577/jpl.ymkj2n
title: Scintillation timescale measurement of the highly active FRB 20201124A

description: Scintillation of compact radio sources is caused by the interference between images caused by multipath propagation, and can be used to probe the intervening scattering plasma, and the velocities of the emitting source and scattering screen. In FRB20201124A, a repeating FRB which recently entered a period of extreme activity, we obtained many burst detections in observations at the Giant Metrewave Radio Telescope (GMRT) and the Effelsberg 100 m Radio Telescope. Nearby bursts show similar scintillation patterns, and we were able to measure a scintillation timescale through the correlation of spectra between burst pairs, the first such measurement for an FRB. In addition, we form the 2D autocorrelation function (ACF) and secondary spectrum of scintillation, which hints towards anisotropic scattering. The inferred scintillation velocity is $V_{\mathrm{ISS}}\approx (64\pm7) \sqrt{d_{l}/2\,\rm{kpc}}~{\rm km~s}^{-1}$, higher than Earth's velocity using the fiducial value of the screen distance. From the measured scintillation bandwidth, we find FRB20201124A to be underscattered by a factor of ~20 compared to the NE2001 model predictions, and lower than nearby pulsars. The underscattering, along with the measured scintillation velocity are consistent with a picture where the scattering screen is more nearby the Earth at d_l ~ 400 pc, rather than at 2 kpc in the spiral arm which NE2001 predicts to be the dominant source of scattering. With future measurements, the distance, geometry, and velocity of the scattering screen could be obtained through modelling of the annual variation in $V_{\rm ISS}$, or through inter-station time delays or VLBI. Scintillation/scattering measurements of FRBs could be used to constrain and improve Galactic electron density models, particularly in the Galactic halo or at high Galactic latitudes.
DOI: 10.48577/jpl.ddqrhq
title: X-Ray Evidence Against the Hypothesis that the Hyper-Luminous z = 6:3 Quasar J0100+2802 is Lensed

description: The z = 6:327 quasar SDSS J010013.02+280225.8 (hereafter J0100+2802) is believed to be powered by ablack hole more massive than 1010 M , making it the most massive black hole known in the first billion yearsof the Universe. However, recent high-resolution ALMA imaging shows four structures at the location of thisquasar, potentially implying that it is lensed with a magnification of 450 and thus its black hole is significantlyless massive. Furthermore, for the underlying distribution of magnifications of z & 6 quasars to producesuch an extreme value, theoretical models predict that a larger number of quasars in this epoch should be lensed,implying further overestimates of early black hole masses. To provide an independent constraint on the possibilitythat J0100+2802 is lensed, we re-analyzed archival XMM-Newton observations of the quasar and comparedthe expected ratios of X-ray luminosity to rest-frame UV and IR luminosities. For both cases, J0100+2802’sX-ray flux is consistent with the no-lensing scenario; while this could be explained by J0100+2802 being Xrayfaint, we find it does not have the X-ray or optical spectral features expected for an X-ray faint quasar.Finally, we compare the overall distribution of X-ray fluxes for known, typical z & 6 quasars. We find a 3 tensionbetween the observed and predicted X-ray-to-UV flux ratios when adopting the magnification probabilitydistribution required to produce a = 450 quasar.
DOI: 10.48577/jpl.u3tvgu
title: Comparative genomics of novel Agrobacterium tomkonis sp. nov. isolated from the International Space Station

description: Strains of Agrobacterium genomospecies 3 (i.e., genomovar G3) have been previously isolated from diverse environments, including in association with plant roots, with algae, as part of a lignocellulose degrading community, from a hospital environment, as a human opportunistic pathogen, or as reported in this study, from a surface within the International Space Station. Polyphasic taxonomic methods revealed their relationship to Agrobacterium genomospecies 3, which further support the description of a novel species. The G3 strains tested (n=9) were phenotypically distinguishable among the strains from other genomospecies of the genus Agrobacterium. Phylogenetic analyses of the 16S rRNA gene, gyrB gene, multi-locus sequence analysis, and 1,089-gene core-genome gene concatenate concur that tested G3 strains belong to the Agrobacterium genus, and they form a clade distinct from other validly described Agrobacterium species. The distinctiveness of this clade was confirmed by average nucleotide identity (ANI) and in silico digital DNA–DNA hybridization (dDDH) comparisons between the G3 tested strains and all known Agrobacterium species type strains, since obtained values were considerably below the 95% (ANI) and 70% (dDDH) thresholds used for the species delineation. Their closest relatives were Rhizobium sp. UGM030330-04 and Agrobacterium rhizogenes (genomospecies 10) strain K599. We thus propose the name Agrobacterium tomkonis for this species previously referred to as Agrobacterium genomospecies 3. The type strain of A. tomkonis is IIF1SW-B1T (=LMG 32164 = NRRL B-65602). Comparative genomic analysis show A. tomkonis strains have species-specific genes associated with secretion of secondary metabolites, including an exopolysaccharide and putative adhesins and resistance to copper.
DOI: 10.48577/jpl.3s7lb9
title: Magnetic Fields and Accreting Giant Planets around PDS 70}

description: The recent high spatial/spectral resolution observations have enabled constraining formation mechanismsof giant planets, especially at the final stages. The current interpretation of such observations isthat these planets undergo magnetospheric accretion, suggesting the importance of planetary magneticfields. We explore the properties of accreting, magnetized giant planets surrounded by their circumplanetarydisks, using the physical parameters inferred for PDS 70 b/c. We compute the magnetic fieldstrength and the resulting spin rate of giant planets, and find that these planets may possess dipolemagnetic fields of either a few 10 G or a few 100 G; the former is the natural outcome of planetarygrowth and radius evolution, while the resulting spin rate cannot reproduce the observations. Forthe latter, a consistent picture can be drawn, where strong magnetic fields induced by hot planetaryinteriors lead both to magnetospheric accretion and to spin-down due to disk locking. We also computethe properties of circumplanetary disks in the vicinity of these planets, taking into account planetarymagnetic fields. The resulting surface density becomes very low, compared with the canonical models,implying the importance of radial movement of satellite-forming materials. Our model predicts a positivegradient of the surface density, which invokes the traps for both satellite migration and radiallydrifting dust particles. This work thus concludes that the final formation stages of giant planets aresimilar to those of low-mass stars such as brown dwarfs, as suggested by recent studies.
DOI: 10.48577/jpl.ivymev
title: Optimized modeling of Gaia-Hipparcos astrometry for the detection of the smallest cold Jupiter and confirmation of seven low mass companions

description: To fully constrain the orbits of low mass circumstellar companions, we conduct combinedanalyses of the radial velocity data as well as the Gaia and Hipparcos astrometric data foreight nearby systems. Our study shows that companion-induced position and proper motiondifferences between Gaia and Hipparcos are significant enough to constrain orbits of low masscompanions to a precision comparable with previous combined analyses of direct imagingand radial velocity data. We find that our method is robust to whether we use Gaia DR2 orGaia EDR3, as well as whether we use all of the data, or just proper motion differences. Inparticular, we fully characterize the orbits of HD 190360 b and HD 16160 C for the first time.With a mass of 1.80.2 𝑀Jup and an effective temperature of 123-176K and orbiting around aSun-like star, HD 190360 b is the smallest Jupiter-like planet with well-constrained mass andorbit, belonging to a small sample of fully characterized Jupiter analogs. It is separated fromits primary star by 0.2500 and thus may be suitable for direct imaging by the CGI instrumentof the Roman Space Telescope.
DOI: 10.48577/jpl.s5hkzq
title: Notes on a Compressible Extended Burgers Model of Rheology

description: Constitutive theory for viscoelasticity has broad application to solid mantle or ice deformations driven by tides, surface mass variations, and post-seismic ﬂow. Geophysical models using higher order viscoelasticity can better accommodate geodetic observations than lower-order theory, typically provided by tensor versions of Maxwell, 4-parameter Burgers or standard linear (Zener) rheology. We encapsulate, for the ﬁrst time, a mathematical description of a compressible version of the extended Burgers material (EBM) model paradigm which has a distribution function of relaxation spectra. The latter model is of-ten used for parameterizing high temperature background transient responses in the rock physics and mechanics laboratory setting and have demonstrated application to low frequency seismic wave attenuation. A new generalization of this practical anelastic model is presented and applied to the glacial isostatic adjustment momentum equations, thus providing useful guidance for generating initial-value boundary problem-solving software for quite general coding strategies. The solutions for the vertical motion response to a suddenly imposed surface load reveal a short-term transience of substantial amplitude.
DOI: 10.48577/jpl.1uo5sy
title: High Voltage Solar Array Development for Space and Thruster-Plume Plasma Environments

description: High power solar arrays are in development by NASA for near term high power solar electric propulsion (SEP) missions. These high voltage solar arrays utilize deployable flexible blanket configurations and need to be able to operate in the plasma environment of high power Hall thrusters operating at 10’s of kilowatts of power. Array voltages of 300 to 800 V are desired both to minimize the copper-bus mass in the system, and to potentially operate the SEP Hall thrusters directly at high specific impulse without an in-series power processing. Coupons with several strings of solar cells are tested to high positive and negative bias in a plasma environment representative of the edge of Hall thruster plumes. Proper encapsulation of the exposed metals and triple-points is required to avoid excessive current collection and arc initiation. Fully encapsulated test coupons have been successfully tested at the highest anticipated thruster-plume plasma densities at voltages from 600-1000 V, which enables both very-high power arrays and direct drive configurations for SEP missions.
DOI: 10.48577/jpl.eg0dro
title: Improved line list of 12CH4 in the 4100-4300 cm-1 region

description: Four spectra of methane in natural isotopic abundance in the 4100-4300 cm-1 region were recorded by using a Fourier transform spectrometer in Reims, France at long paths (202 m, 602 m, 1604 m and 1804 m) and different pressures. Additional spectra of 12CH4 covering the same region were obtained at 100-123 K for different pressures, 93 m path length at Synchrotron SOLEIL in Paris for different pressures and were used to measure low-J lines. Spectra of 12CH4 and 13CH4 obtained at 80 K at JPL were used for additional frequency calibrations. Line positions and intensities were retrieved by non-linear least-squares curve-fitting procedures and analyzed using effective Hamiltonian and effective dipole transition moment models. A new measured line list contains positions and intensities for 12274 features. Quantum assignments were made for more than 11472 new transitions, which represent ~99% of the integrated line intensity observed in this region. Some of 4592 hot band transitions for (Dyad – Tetradecad) system were assigned. The resulting list of lines is significantly more accurate than previous empirical compilations. All assigned 6972 line positions were fitted to RMS standard deviations of 0.0015 cm-1. The sum of the observed intensities between 4100 and 4300 cm-1 falls within 5% of the predicted value from ab initio variational calculations reported in the TheoReTS database (http://theorets.univ-reims.fr ; http://theorets.tsu.ru).
DOI: 10.48577/jpl.rkvc5z
title: 500-A LaB6 Hollow Cathode for High Power Electric Thrusters

description: NASA continues to develop higher power ion and Hall thrusters for deep space human and robotic missions that require higher thrust and specific impulse than available in current thrusters. The NASA NextSTEP program produced a successful demonstration the XR-100 nested Hall thruster system operating at 100 kW of power; driven by a JPL LaB6 hollow cathode operating at 250 A of discharge current. This X3 hollow cathode represents the state-of-the-art in high current thruster cathodes and has been operated at 25-350A of discharge current in the JPL cathode test facility. The next generation of this LaB6 hollow cathode has been designed and built at JPL and tested at up to 500 A of discharge current. Extending the current to this high a level was challenging, with iterations in the design necessary to provide adequate thermal isolation of the insert to lower the heater power required to ignite, to achieve sufficient keeper discharge current to aid in the startup, and to maintain the cathode orifice plate at acceptable temperatures during very high current operation. The cathode configuration that achieved 500 A discharge current operation is described, along with discussions about energetic ion suppression, plasma penetration into the insert region, and cathode life.
DOI: 10.48577/jpl.6fkkep
title: Keck/OSIRIS Paβ high-contrast imaging and updated constraints on PDS 70b

description: We present a high-contrast imaging search for Pa line emission from protoplanets in the PDS 70 system with Keck/OSIRIS integral field spectroscopy. We applied the high-resolution spectral differential imaging technique to the OSIRIS J-band data but did not detect the Pa line at the level predicted using the parameters of Hashimoto et al. (2020). This lack of Pa emission suggests the MUSE-based study may have overestimated the line width of H. We compared our Pa detection limits with the previous H flux and H limits and estimated AV to be 0:9 and 2.0 for PDS 70 b and c respectively. In particular, PDS 70 b’s AV is much smaller than implied by high-contrast near-infrared studies, which suggests the infrared-continuum photosphere and the hydrogen-emitting regions exist at different heights above the forming planet.
DOI: 10.48577/jpl.8cdhsv
title: Conditioning Jovian Burst Signals for Passive Sounding Applications

description: Passively sounding icy and rocky bodies in our Solar System provides a way to observe the surface and subsurface of these objects without the need for costly transmitters. Jupiter's decametric radiation provides a suitable source of radio-frequency signals for sounding on geological scales of interest, but its spectral structure can introduce undesired artifacts. We present conditioning processes that improve the echo detectability and sounding resolution for Jovian burst-like signals. More than 18 hours of Jovian burst recordings are used to simulate conditioning of the natural spectral variation demonstrating high-quality corrections are possible with these processes for noise conditions in the Jovian and Earth/Moon systems.
DOI: 10.48577/jpl.w7f3py
title: Multi-frequency Full-wave Simulations of Vegetation Using a Hybrid Method

description: In this paper, we study wave propagation in vegetationat multiple frequencies using a hybrid method. Firstly, themultiple scattering within a single plant is captured using theHigh-Frequency Structure Simulator (HFSS) for extracting theT-matrix of the plant in vector cylindrical waves. Secondly, theFoldy-Lax equations are applied with the extracted T-matricesto consider the multiple scattering among different plants. Theaccuracy of the hybrid method is verified by comparing the scatteringresults from 9 wheat plants with direct HFSS simulations.The hybrid method is implemented with parallel computing usinga physical iterative method to perform full-wave Monte Carlosimulations of a wheat field with up to 169 plants at L-, S- andC-bands. The impact of the gaps and the plant structure on themicrowave propagations are studied by assessing the scatteredfields and the resulting non-uniform transmission at differentregions. The results are compared with modeling results usingthe classical radiative transfer equations (RTE), and two majordifferences are observed: (1) the transmission calculated fromthe hybrid method is much larger than that of the RTE, and (2)the full-wave simulation results show much weaker frequencydependence than RTE with a saturation as frequency increases.
DOI: 10.48577/jpl.fo8mka
title: Recent increases in exposure to extreme humid-heat events disproportionately affect populated regions

description: Extreme heat research has largely focussed on dry-heat, while humid-heat that poses a substantial threat to human-health remains relatively understudied. Using hourly high-resolution ERA5 reanalysis and HadISD station data, we provide the first spatially-comprehensive, global-scale characterisation of the magnitude, seasonal timing, and frequency of dry- and wet-bulb temperature extremes and their trends. While the peak dry- and humid-heat extreme occurrences often coincide, their timing differs in climatologically-wet regions. Since 1979, dry- and humid-heat extremes have become more frequent over most land regions, with the greatest increases in the tropics and Arctic. Humid-heat extremes have increased disproportionately over populated regions (~5.0 days per-person per-decade) relative to global land-areas (~3.6 days per-unit-land-area per-decade) and population exposure to humid-heat has increased at a faster rate than to dry-heat. Our study highlights the need for a multivariate approach to understand and mitigate future harm from heat stress in a warming world.
DOI: 10.48577/jpl.puaouz
title: Testing stomatal models at stand level in deciduous angiosperm and evergreen gymnosperm forests using CliMA Land (v0.1)

description: At the leaf level, stomata control the exchange of water and carbon across the air-leaf interface. Stomatal conduc- tance is typically modeled empirically, based on environmental conditions at the leaf surface. Recently developed stomatal optimization models show great skills at predicting carbon and water fluxes at both the leaf and tree levels. However, it has not been extensively evaluated how well the optimization models perform at larger scales. Furthermore, stomatal models are5 often used with simple single-leaf representations of canopy radiative transfer (RT), such as big-leaf models. Nevertheless, the single-leaf canopy RT schemes do not have the capability to model optical properties of the leaves or the entire canopy. As a result, they are unable to directly link canopy optical properties with light distribution within the canopy to remote sensing data observed from afar. Here we incorporated one optimization-based and two empirical stomatal models with a comprehensive RT model in the land component of a new Earth System model within CliMA, the Climate Modelling Alliance. The model allowed10 us to simultaneously simulate carbon and water fluxes as well as leaf and canopy reflectance and fluorescence spectra. We tested our model by comparing our modeled carbon and water fluxes and solar-induced chlorophyll fluorescence (SIF) to two flux tower observations (a gymnosperm forest and an angiosperm forest) and satellite SIF retrievals, respectively. All three stomatal models quantitatively predicted the carbon and water fluxes for both forests. The optimization model, in particular, showed increased skill in predicting the water flux given the lower error (c. 14.2% and 21.8% improvement for the gymnosperm and15 angiosperm forests, respectively) and better 1:1 comparison (slope increases from c. 0.34 to 0.91 for the gymnosperm forest, and from c. 0.38 to 0.62 for the angiosperm forest). Our model also predicted the SIF yield, quantitatively reproducing seasonal cycles for both forests. We found that using stomatal optimization with a comprehensive RT model showed high accuracy in simulating land surface processes. The ever-increasing number of regional and global datasets of terrestrial plants, such as leaf area index and chlorophyll contents, will help parameterize the land model and improve future Earth System modeling in20 general.
DOI: 10.48577/jpl.sl0yem
title: Decadal to Centennial Timescale Mantle Viscosity Inferred from Modern Crustal Uplift Rates in Greenland

description: The observed crustal uplift rates in Greenland are caused by the combined response of the solid Earth to both ongoing and past surface mass changes. Existing elastic Earth models and Maxwell linear viscoelastic GIA (glacial isostatic adjustment) models together underpredict the observed uplift rates. These models do not capture the ongoing mantle deformation induced by significant ice melting since the Little Ice Age. Using a simple Earth model within a Bayesian framework, we show that this recent mass loss can explain the data-model misfits but only when a reduced mantle strength is considered. The inferred viscosity for sub-centennial timescale mantle deformation is roughly one order of magnitude smaller than the upper mantle viscosity inferred from GIA analysis of geological sea-level data. Reconciliation of geological sea-level and modern crustal motion data may require that the model effective viscosity be treated with greater sophistication than in the simple Maxwell rheological paradigm.