bluuebunny/crossref_metadata_2025_split huggingface dataset:
“Super-deblended” Dust Emission in Galaxies. I. The GOODS-North Catalog and the Cosmic Star Formation Rate Density out to Redshift 6
Authors: Liu Daizhong , Daddi Emanuele , Dickinson Mark , Owen Frazer , Pannella Maurilio , Sargent Mark , Béthermin Matthieu , Magdis Georgios , Gao Yu , Shu Xinwen , Wang Tao , Jin Shuowen , Inami Hanae 
Published: February 2018

Abstract
We present a new technique to measure multi-wavelength “super-deblended” photometry from highly confused images, which we apply to Herschel and ground-based far-infrared (FIR) and (sub-)millimeter (mm) data in the northern field of the Great Observatories Origins Deep Survey. There are two key novelties. First, starting with a large database of deep Spitzer 24 μm and VLA 20 cm detections that are used to define prior positions for fitting the FIR/submm data, we perform an active selection of useful priors independently at each frequency band, moving from less to more confused bands. Exploiting knowledge of redshift and all available photometry, we identify hopelessly faint priors that we remove from the fitting pool. This approach significantly reduces blending degeneracies and allows reliable photometry to be obtained for galaxies in FIR+mm bands. Second, we obtain well-behaved, nearly Gaussian flux density uncertainties, individually tailored to all fitted priors for each band. This is done by exploiting extensive simulations that allow us to calibrate the conversion of formal fitting uncertainties to realistic uncertainties, depending on directly measurable quantities. We achieve deeper detection limits with high fidelity measurements and uncertainties at FIR+mm bands. As an illustration of the utility of these measurements, we identify 70 galaxies with

and reliable FIR+mm detections. We present new constraints on the cosmic star formation rate density at

, finding a significant contribution from

dusty galaxies that are missed by optical-to-near-infrared color selection. Photometric measurements for 3306 priors, including more than 1000 FIR+mm detections, are released publicly with our catalog.
Impact of Neutrino Opacities on Core-collapse Supernova Simulations
Authors: Kotake Kei , Takiwaki Tomoya , Fischer Tobias , Nakamura Ko , Martínez-Pinedo Gabriel 
Published: February 2018

Abstract
The accurate description of neutrino opacities is central to both the core-collapse supernova (CCSN) phenomenon and the validity of the explosion mechanism itself. In this work, we study in a systematic fashion the role of a variety of well-selected neutrino opacities in CCSN simulations where the multi-energy, three-flavor neutrino transport is solved using the isotropic diffusion source approximation (IDSA) scheme. To verify our code, we first present results from one-dimensional (1D) simulations following the core collapse, bounce, and ∼250 ms postbounce of a

star using a standard set of neutrino opacities by Bruenn. A detailed comparison with published results supports the reliability of our three-flavor IDSA scheme using the standard opacity set. We then investigate in 1D simulations how individual opacity updates lead to differences with the baseline run with the standard opacity set. Through detailed comparisons with previous work, we check the validity of our implementation of each update in a step-by-step manner. Individual neutrino opacities with the largest impact on the overall evolution in 1D simulations are selected for systematic comparisons in our two-dimensional (2D) simulations. Special attention is given to the criterion of explodability in the 2D models. We discuss the implications of these results as well as its limitations and the requirements for future, more elaborate CCSN modeling.
Morphology and Kinematics of Filaments in the Serpens and Perseus Molecular Clouds
Authors: Dhabal Arnab , Mundy Lee G. , Rizzo Maxime J. , Storm Shaye , Teuben Peter 
Published: February 2018

Abstract
We present H13CO+ (J = 1–0) and HNC (J = 1–0) maps of regions in Serpens South, Serpens Main, and NGC 1333 containing filaments. We also observe the Serpens regions using H13CN (J = 1–0). These dense gas tracer molecular line observations carried out with CARMA have an angular resolution of ∼7″, a spectral resolution of ∼0.16 km s−1, and a sensitivity of 50–100 mJy beam−1. Although the large-scale structure compares well with the Herschel dust continuum maps, we resolve finer structure within the filaments identified by Herschel. The H13CO+ emission distribution agrees with the existing CARMA N2H+ (J = 1–0) maps, so they trace the same morphology and kinematics of the filaments. The H13CO+ maps additionally reveal that many regions have multiple structures partially overlapping in the line of sight. In two regions, the velocity differences are as high as 1.4 km s−1. We identify eight filamentary structures having typical widths of 0.03–0.08 pc in these tracers. At least 50% of the filamentary structures have distinct velocity gradients perpendicular to their major axis, with average values in the range of 4–10 km s−1 pc−1. These findings are in support of the theoretical models of filament formation by 2D inflow in the shock layer created by colliding turbulent cells. We also find evidence of velocity gradients along the length of two filamentary structures; the gradients suggest that these filaments are inflowing toward the cloud core.
MPI-AMRVAC 2.0 for Solar and Astrophysical Applications
Authors: Xia C. , Teunissen J. , Mellah I. El , Chané E. , Keppens R. 
Published: February 2018

Abstract
We report on the development of MPI-AMRVAC version 2.0, which is an open-source framework for parallel, grid-adaptive simulations of hydrodynamic and magnetohydrodynamic (MHD) astrophysical applications. The framework now supports radial grid stretching in combination with adaptive mesh refinement (AMR). The advantages of this combined approach are demonstrated with one-dimensional, two-dimensional, and three-dimensional examples of spherically symmetric Bondi accretion, steady planar Bondi–Hoyle–Lyttleton flows, and wind accretion in supergiant X-ray binaries. Another improvement is support for the generic splitting of any background magnetic field. We present several tests relevant for solar physics applications to demonstrate the advantages of field splitting on accuracy and robustness in extremely low-plasma β environments: a static magnetic flux rope, a magnetic null-point, and magnetic reconnection in a current sheet with either uniform or anomalous resistivity. Our implementation for treating anisotropic thermal conduction in multi-dimensional MHD applications is also described, which generalizes the original slope-limited symmetric scheme from two to three dimensions. We perform ring diffusion tests that demonstrate its accuracy and robustness, and show that it prevents the unphysical thermal flux present in traditional schemes. The improved parallel scaling of the code is demonstrated with three-dimensional AMR simulations of solar coronal rain, which show satisfactory strong scaling up to 2000 cores. Other framework improvements are also reported: the modernization and reorganization into a library, the handling of automatic regression tests, the use of inline/online Doxygen documentation, and a new future-proof data format for input/output.
Characterizing Accreting Double White Dwarf Binaries with the Laser Interferometer Space Antenna and Gaia
Authors: Breivik Katelyn , Kremer Kyle , Bueno Michael , Larson Shane L. , Coughlin Scott , Kalogera Vassiliki 
Published: February 2018

Abstract
We demonstrate a method to fully characterize mass-transferring double white dwarf (DWD) systems with a helium-rich (He) white dwarf (WD) donor based on the mass–radius (M–R) relationship for He WDs. Using a simulated Galactic population of DWDs, we show that donor and accretor masses can be inferred for up to ∼60 systems observed by both Laser Interferometer Space Antenna (LISA) and Gaia. Half of these systems will have mass constraints

and

. We also show how the orbital frequency evolution due to astrophysical processes and gravitational radiation can be decoupled from the total orbital frequency evolution for up to ∼50 of these systems.
A contrastive morphological analysis of tense formation in Igbo and Yoruba: implication on learners and teachers
Authors: Uwaezuoke Aghaegbuna Haroldson , Ogunkeye Olufunmilayo M. 
Published: February 2018

This paper is a contrastive morphological study of tenses in the Igbo and Yoruba languages. It is limited to tenses only excluding aspects. It intends to aid speakers of the two languages in their effort to learn another’s language. This is considered vital since the two languages are among the major languages in Nigeria and people have become interested in learning them. Globalization has also necessitated the transfer of technological information into these languages, thus making this paper an invaluable one. Data for the two languages are collected from the primary and secondary sources in addition to the researchers’ intuitive knowledge of the languages. Data are analyzed using a contrastive analysis approach. Our findings show that there are differences in the processes of forming tenses in both languages. For instance, Igbo has indicative suffix –rV which may be deleted or optionally used with certain verbs in the present, and obligatorily used for verbs in the past, but in Yoruba, the present tense and past tense are unmarked. A hyphen is written between the future morpheme and the verb in Igbo, but Yoruba has a separate free morpheme to express the future. Also, in Igbo the 1st person singular pronoun and the 3rd person plural pronoun can come after the future morpheme –ga which is prefixed with a followed by the prefixed verbroot, but in Yoruba all the subject pronouns come before the future morpheme. These areas of differences are predicted by contrastive analysis as constituting learning difficulties. This paper proffers solution to the perceived tense problem by advocating that teachers should be more attentive to their students’ speeches and write-ups in order to immediately correct any error that might occur. They should avail themselves of the available materials on contrastive analysis such as this and guide the students to know the formation of tenses in these languages and immediately correct any error that might occur or better prevent the errors from manifesting.
Sea cucumbers reduce chromophoric dissolved organic matter in aquaculture tanks
Authors: Sadeghi-Nassaj Seyed Mohammad , Catalá Teresa S. , Álvarez Pedro A. , Reche Isabel 
Published: February 2018

Background
Mono-specific aquaculture effluents contain high concentrations of nutrients and organic matter, which affect negatively the water quality of the recipient ecosystems. A fundamental feature of water quality is its transparency. The fraction of dissolved organic matter that absorbs light is named chromophoric dissolved organic matter (CDOM). A sustainable alternative to mono-specific aquaculture is the multitrophic aquaculture that includes species trophically complementary named “extractive” species that uptake the waste byproducts. Sea cucumbers are recognized as efficient extractive species due to the consumption of particulate organic matter (POM). However, the effects of sea cucumbers on CDOM are still unknown.

Methods
During more than one year, we monitored CDOM in two big-volume tanks with different trophic structure. One of the tanks (−holothurian) only contained around 810 individuals of Anemonia sulcata, whereas the other tank (+holothurian) also included 90 individuals of Holothuria tubulosa and Holothuria forskali. We routinely analyzed CDOM absorption spectra and determined quantitative (absorption coefficients at 325 nm) and qualitative (spectral slopes) optical parameters in the inlet waters, within the tanks, and in their corresponding effluents. To confirm the time-series results, we also performed three experiments. Each experiment consisted of two treatments: +holothurians (+H) and –holothurians (−H). We set up three +H tanks with 80 individuals of A. sulcata and 10 individuals of H. tubulosa in each tank and four –H tanks that contained only 80 individuals of A. sulcata.

Results
In the time-series, absorption coefficients at 325 nm (a325) and spectral slopes from 275 to 295 nm (S275−295) were significantly lower in the effluent of the +holothurian tank (average: 0.33 m−1 and 16 µm−1, respectively) than in the effluent of the −holothurian tank (average: 0.69 m−1 and 34 µm−1, respectively), the former being similar to those found in the inlet waters (average: 0.32 m−1 and 22 µm−1, respectively). This reduction in the absorption of the dissolved organic matter appears to be mediated by the POM consumption by holothurians. The experiments confirmed the results observed in the time-series. The a325 and S275−295 values were significantly lower in the treatment with holothurians than in the treatment without holothurians indicating a reduction in the concentration of chromophoric organic compounds, particularly of low molecular weight.

Discussion
Consequently, sea cucumbers appear to improve water transparency in aquaculture tanks. The underlying mechanism of this improvement might be related to the POM consumption by holothurians, which reduces the concentration of CDOM derived from POM disaggregation or to the direct assimilation of dissolved compounds of low molecular weight as chromophoric amino acids.
Application of an Anisotropy‐Based Correction to Relative Paleointensity Estimates of Experimentally Deposited Sediments
Authors: Molinek F. R. , Bilardello D. 
Published: February 2018

AbstractThe magnetization of a sediment is acquired when ferromagnetic detrital particles align with the Earth's magnetic field as they settle through the water column. The relative continuity and ubiquity of the global sedimentary record makes sediments and sedimentary rocks an ideal target for studies of relative paleointensity (RPI) and the evolution of the Earth's magnetic field. However, processes including flocculation, contact with the substrate, bioturbation, and compaction disrupt this alignment, leading to shallowed remanent inclinations and biased intensities. The inclination of the depositional field also exerts an influence on the remanent intensity, thus affecting RPI estimates and leading to complications in interpretations of the global record. We present a series of 12 deposition experiments conducted in varying field strengths and inclinations, from which we determine RPI estimates. We then correct these estimates using a modified anisotropy‐based inclination correction technique. We find experimentally that our correction reduces the inclination dependence of relative paleointensity while preserving the RPI's dependence on the depositional intensity. Our results suggest that the anisotropy‐based correction should improve RPI estimates obtained from natural sediments and sedimentary rocks.
Modeling Slab‐Slab Interactions: Dynamics of Outward Dipping Double‐Sided Subduction Systems
Authors: Király Ágnes , Holt Adam F. , Funiciello Francesca , Faccenna Claudio , Capitanio Fabio A. 
Published: February 2018

AbstractSlab‐slab interaction is a characteristic feature of tectonically complex areas. Outward dipping double‐sided subduction is one of these complex cases, which has several examples on Earth, most notably the Molucca Sea and Adriatic Sea. This study focuses on developing a framework for linking plate kinematics and slab interactions in an outward dipping subduction geometry. We used analog and numerical models to better understand the underlying subduction dynamics. Compared to a single subduction model, double‐sided subduction exhibits more time‐dependent and vigorous toroidal flow cells that are elongated (i.e., not circular). Because both the Molucca and Adriatic Sea exhibit an asymmetric subduction configuration, we also examine the role that asymmetry plays in the dynamics of outward dipping double‐sided subduction. We introduce asymmetry in two ways; with variable initial depths for the two slabs (“geometric” asymmetry), and with variable buoyancy within the subducting plate (“mechanical” asymmetry). Relative to the symmetric case, we probe how asymmetry affects the overall slab kinematics, whether asymmetric behavior intensifies or equilibrates as subduction proceeds. While initial geometric asymmetry disappears once the slabs are anchored to the 660 km discontinuity, the mechanical asymmetry can cause more permanent differences between the two subduction zones. In the most extreme case, the partly continental slab stops subducting due to the unequal slab pull force. The results show that the slab‐slab interaction is most effective when the two trenches are closer than 10–8 cm in the laboratory, which is 600–480 km when scaled to the Earth.
The Magmatic Gas Signature of Pacaya Volcano, With Implications for the Volcanic CO2 Flux From Guatemala
Authors: Battaglia A. , Bitetto M. , Aiuppa A. , Rizzo A.L. , Chigna G. , Watson I. M. , D'Aleo R. , Juárez Cacao F. J. , de Moor M. J. 
Published: February 2018

AbstractPacaya volcano in Guatemala is one of the most active volcanoes of the Central American Volcanic Arc (CAVA). However, its magmatic gas signature and volatile output have received little attention to date. Here, we present novel volcanic gas information from in‐situ (Multi‐GAS) and remote (UV camera) plume observations in January 2016. We find in‐plume H2O/SO2 and CO2/SO2 ratios of 2‐20 and 0.6‐10.5, and an end‐member magmatic gas signature of 80.5 mol. % H2O, 10.4 mol. % CO2, and 9.0 mol. % SO2. The SO2 flux is evaluated at 885 ± 550 tons/d. This, combined with co‐acquired volcanic plume composition, leads to H2O and CO2 fluxes of 2,230 ± 1,390 and 700 ± 440, and a total volatile flux of ∼3,800 tons/d. We use these results in tandem with previous SO2 flux budgets for Fuego and Santiaguito to estimate the total volcanic CO2 flux from Guatemala at ∼1,160 ± 600 tons/day. This calculation is based upon CO2/total S (St) ratios for Fuego (1.5 ± 0.75) and Santiaguito (1.4 ± 0.75) inferred from a gas (CO2/St ratio) versus trace‐element (Ba/La ratio) CAVA relationship. The H2O‐poor and low CO2/St ratio (∼1.0‐1.5) signature of Pacaya gas suggests dominant mantle‐wedge derivation of the emitted volatiles. This is consistent with 3He/4He ratios in olivine hosted fluid inclusions (FIs), which range between 8.4 and 9.0 Ra (being Ra the atmospheric 3He/4He ratio) at the upper limit of MORB range (8 ± 1 Ra). These values are the highest ever measured in CAVA and among the highest ever recorded in arc volcanoes worldwide, indicating negligible 4He contributions from the crust/slab.
Phytoplankton Community Structure in 2011–2013 Compared to the Extratropical Warming Event of 2014–2015
Authors: Du X. , Peterson W. T. 
Published: February 2018

AbstractCoastal waters of the Northern California Current experienced “normal” ocean conditions in 2011–2012, weak upwelling in 2013–2014, then suddenly warmed in September 2014. The response of phytoplankton community structure to contrasting ocean conditions was determined from samples collected off Newport, Oregon. Cluster analysis identified three prominent phytoplankton community types: one that occurred during the upwelling season characterized by the highest abundance and diversity of diatoms, a preupwelling/relaxation community characterized by lower abundance, lowest diversity of diatoms and dinoflagellates, and another one associated with the warm anomalies from September 2014 through 2015 with reduced diatom abundance and diversity but the highest dinoflagellate diversity. The changes of diatom and dinoflagellate community were correlated with local factors (silicate, silicate: nitrate ratios, temperature, and salinity), and with the Pacific Decadal Oscillation.
Space‐Weathered Anorthosite as Spectral D‐Type Material on the Martian Satellites
Authors: Yamamoto S. , Watanabe S. , Matsunaga T. 
Published: February 2018

AbstractSpectral D‐type asteroids are characterized by dark, red‐sloped, and featureless spectra at visible and near‐infrared wavelengths and are thought to be composed of rocks rich in organic compounds. The Martian satellites, Phobos and Deimos, spectrally resemble D‐type asteroids, suggesting that they are captured D‐type asteroids from outside the Martian system. Here we show that the spectral features of lunar space‐weathered anorthosite are consistent with D‐type spectra, including those of Phobos and Deimos. This can also explain the distinct spectral features on Phobos, the red and blue units, as arising from different degrees of space weathering. Thus, D‐type spectra of the Martian satellites can be explained by space‐weathered anorthosite, indicating that D‐type spectra do not necessarily support the existence of organic compounds, which would be strong evidence for the capture scenario.
Response of the Land‐Atmosphere System Over North‐Central Oklahoma During the 2017 Eclipse
Authors: Turner D. D. , Wulfmeyer V. , Behrendt A. , Bonin T. A. , Choukulkar A. , Newsom R. K. , Brewer W. A. , Cook D. R. 
Published: February 2018

AbstractOn 21 August 2017, a solar eclipse occurred over the continental United States resulting in a rapid reduction and subsequent increase of solar radiation over a large region of the country. The eclipse's effect on the land‐atmosphere system is documented in unprecedented detail using a unique array of sensors deployed at three sites in north‐central Oklahoma. The observations showed that turbulent fluxes of heat and momentum at the surface responded quickly to the change in solar radiation. The decrease in the sensible heat flux resulted in a decrease in the air temperature below 200 m, and a large decrease in turbulent motions throughout the boundary layer. Furthermore, the turbulent mixing in the boundary layer lagged behind the change in the surface fluxes, and this lag depended on the height above the surface. The turbulent motions increased and the convective boundary layer was reestablished as the sensible heat flux recovered.
MMS Examination of FTEs at the Earth's Subsolar Magnetopause
Authors: Akhavan‐Tafti M. , Slavin J. A. , Le G. , Eastwood J. P. , Strangeway R. J. , Russell C. T. , Nakamura R. , Baumjohann W. , Torbert R. B. , Giles B. L. , Gershman D. J. , Burch J. L. 
Published: February 2018

AbstractDetermining the magnetic field structure, electric currents, and plasma distributions within flux transfer event (FTE)‐type flux ropes is critical to the understanding of their origin, evolution, and dynamics. Here the Magnetospheric Multiscale mission's high‐resolution magnetic field and plasma measurements are used to identify FTEs in the vicinity of the subsolar magnetopause. The constant‐α flux rope model is used to identify quasi‐force free flux ropes and to infer the size, the core magnetic field strength, the magnetic flux content, and the spacecraft trajectories through these structures. Our statistical analysis determines a mean diameter of 1,700 ± 400 km (~30 ± 9 di) and an average magnetic flux content of 100 ± 30 kWb for the quasi‐force free FTEs at the Earth's subsolar magnetopause which are smaller than values reported by Cluster at high latitudes. These observed nonlinear size and magnetic flux content distributions of FTEs appear consistent with the plasmoid instability theory, which relies on the merging of neighboring, small‐scale FTEs to generate larger structures. The ratio of the perpendicular to parallel components of current density, RJ, indicates that our FTEs are magnetically force‐free, defined as RJ < 1, in their core regions (<0.6 Rflux rope). Plasma density is shown to be larger in smaller, newly formed FTEs and dropping with increasing FTE size. It is also shown that parallel ion velocity dominates inside FTEs with largest plasma density. Field‐aligned flow facilitates the evacuation of plasma inside newly formed FTEs, while their core magnetic field strengthens with increasing FTE size.