Miracle-dz/UniFAR-FTUs huggingface dataset:
Radiative emission of solar features in the Ca II K line: comparison of measurements and models

Context. The intensity of the Ca II K resonance line observed with spectrographs and Lyot-type filters has long served as a diagnostic of the solar chromosphere. However, the literature contains a relative lack of photometric measurements of solar features observed at this spectral range. Aims. We study the radiative emission of various types of solar features, such as quiet Sun, enhanced network, plage, and bright plage regions, identified on filtergrams taken in the Ca II K line. Methods. We analysed full-disk images obtained with the PSPT, by using three interference filters that sample the Ca II K line with different bandpasses. We studied the dependence of the radiative emission of disk features on the filter bandpass. We also performed a non-local thermal equilibrium (NLTE) spectral synthesis of the Ca II K line integrated over the bandpass of PSPT filters. The synthesis was carried out by utilizing the partial frequency redistribution (PRD) with the most recent set of semi-empirical atmosphere models in the literature and some earlier atmosphere models. As the studied models were computed by assuming the complete redistribution formalism (CRD), we also performed simulations with this approximation for comparison. Results. We measured the center-to-limb variation of intensity values for various solar features identified on PSPT images and compared the results obtained with those derived from the synthesis. We find that CRD calculations derived using the most recent quiet Sun model, on average, reproduce the measured values of the quiet Sun regions slightly more accurately than PRD computations with the same model. This may reflect that the utilized atmospheric model was computed assuming CRD. Calculations with PRD on earlier quiet Sun model atmospheres reproduce measured quantities with a similar accuracy as to that achieved here by applying CRD to the recent model. We also find that the median contrast values measured for most of the identified bright features, disk positions, and filter bandpasses are, on average, a factor ≈1.9 lower than those derived from PRD simulations performed using the recent bright feature models. The discrepancy between measured and modeled values decreases by ≈12% after taking into account straylight effects on PSPT images. When moving towards the limb, PRD computations display closer agreement with the data than performed in CRD. Moreover, PRD computations on either the most recent or the earlier atmosphere models of bright features reproduce measurements from plage and bright plage regions with a similar accuracy.
Individual Tree Species Classification Based on a Hierarchical Convolutional Neural Network and Multitemporal Google Earth Images

Accurate and efficient individual tree species (ITS) classification is the basis of fine forest resource management. It is a challenge to classify individual tree species in dense forests using remote sensing imagery. In order to solve this problem, a new ITS classification method was proposed in this study, in which a hierarchical convolutional neural network (H-CNN) model and multi-temporal high-resolution Google Earth images were employed. In an experiment conducted in a forest park in Beijing, China, GE images of several significant phenological phases of broad-leaved forests, namely, before and after the mushrooming period, the growth period, and the wilting period, were selected, and ITS classifications based on these images along with several typical CNN models and the H-CNN model were conducted. In the experiment, the classification accuracy of the multitemporal images was higher by 7.08–12.09% than those of the single-temporal images, and the H-CNN model offered an OA accuracy 2.66–3.72% higher than individual CNN models, demonstrating that multitemporal images rich in the phenological features of individual tree species, together with a hierarchical CNN model, can effectively improve ITS classification.
Holographic charge transport in 2+1 dimensions at finite N

We study holographic charge transport in (2+1) dimensions at finite N, whose dual gravity background is given by perturbative black hole solution in Einstein theory plus cubic terms of Weyl tensor. We consider the higher derivative corrections to the standard Maxwell action, given by the interacting terms between the Weyl tensor and the field strength. We calculate the DC conductivity by using both the membrane paradigm and the Kubo's formula and find precise agreement. We compute the AC conductivity and find an analog of the crossover from "metal" to "bad metal" in the low frequency limit. Moreover, the conductivity becomes a constant in the large frequency limit. We derive two universal relations for the Green's functions and observe that they are exactly the same as the infinite N counterparts.
ON THE NATURE OF SODIUM EXCESS OBJECTS. I. DATA AND OBSERVED TRENDS

Several studies have reported the presence of sodium excess objects having neutral atomic absorption lines at 5895 Å (Na D) and 8190 Å that are deeper than expected based on stellar population models that match the stellar continuum. The origin of these lines is therefore hotly debated. van Dokkum & Conroy proposed that low-mass stars (≲0.3 M☉) are more prevalent in massive early-type galaxies, which may lead to a strong Na i 8190 line strength. It is necessary to test this prediction, however, against other prominent optical line indices such as Na D, Mg b, and Fe 5270, which can be measured with a significantly higher signal-to-noise ratio than Na i 8190. We identified a new sample of roughly 1000 Na D excess objects (NEOs; ∼8% of galaxies in the sample) based on Na D line strength in the redshift range 0.00 ⩽ z ⩽ 0.08 from the Sloan Digital Sky Survey (SDSS) DR7 through detailed analysis of galaxy spectra. We explore the properties of these new objects here. The novelty of this work is that the galaxies were carefully identified through direct visual inspection of SDSS images, and we systematically compared the properties of NEOs and those of a control sample of galaxies with normal Na D line strengths. We note that the majority of galaxies with high velocity dispersions (σe > 250 km s−1) show Na D excesses. Most late-type NEOs have strong Hβ line strengths and significant emission lines, which are indicative of the presence of young stellar populations. This result implies that the presence of the interstellar medium and/or dust contributes to the increase in Na D line strengths observed for these galaxies, which is in good agreement with the earlier study of Chen et al. who used the Na D line index to study outflow activity in star-forming disk galaxies. In contrast, the majority of early-type NEOs are predominantly luminous and massive systems, which is in agreement with the findings of van Dokkum & Conroy. However, we find that models used to reproduce the Na i 8190 line strengths that adopt a bottom-heavy initial mass function are not able to reproduce the observed Na D line strengths. By comparing the observed Na D, Mg b, and Fe 5270 line strengths with those of the models, we identify a plausible range of parameters that reproduce the observed values. In these models, the majority of early-type NEOs are “α-enhanced” ([α/Fe] ∼ 0.3), “metal-rich” ([Z/H] ∼ 0.3), and, especially, “Na-enhanced” ([Na/Fe] ∼ 0.3). An enhanced Na abundance is a particularly compelling hypothesis for the increase in the strength of the Na D line index in our early-type NEOs that appear devoid of dust, both in their SDSS images and spectra.
C/O ABUNDANCE RATIOS, IRON DEPLETIONS, AND INFRARED DUST FEATURES IN GALACTIC PLANETARY NEBULAE

We study the dust present in 56 Galactic planetary nebulae (PNe) through their iron depletion factors, their C/O abundance ratios (in 51 objects), and the dust features that appear in their infrared spectra (for 33 objects). Our sample objects have deep optical spectra of good quality, and most of them also have ultraviolet observations. We use these observations to derive the iron abundances and the C/O abundance ratios in a homogeneous way for all the objects. We compile detections of infrared dust features from the literature and we analyze the available Spitzer/IRS spectra. Most of the PNe have C/O ratios below one and show crystalline silicates in their infrared spectra. The PNe with silicates have C/O <1, with the exception of Cn 1-5. Most of the PNe with dust features related to C-rich environments (SiC or the 30 μm feature usually associated to MgS) have C/O ≳ 0.8. Polycyclic aromatic hydrocarbons are detected over the full range of C/O values, including 6 objects that also show silicates. Iron abundances are low in all the objects, implying that more than 90% of their iron atoms are deposited into dust grains. The range of iron depletions in the sample covers about two orders of magnitude, and we find that the highest depletion factors are found in C-rich objects with SiC or the 30 μm feature in their infrared spectra, whereas some of the O-rich objects with silicates show the lowest depletion factors.
Structural tristability and deep Dirac states in bilayer silicene on Ag(111) surfaces

tobethemonolayersiliceneinthepast[Chenetal. ,Phys.Rev.Lett.110,085504(2013)]isidentifiedasthebilayer silicene on the Ag(111) surface. The identification is based on our accurate density-functional calculations in whichthreeapproximations,thelocaldensityapproximation,thegeneralized-gradientapproximation,andthevan der Waals density-functional approximation, to the exchange-correlation energy have been carefully examined. We find that the structural tristability exists for the √ 3 × √ 3 bilayer silicene. The calculated energy barriers among the three stable structures are in the range of 7‐9 meV per Si atom, indicating possible flip-flop motions among the three. We have found that the flip-flop motion between two of the three structures produces the honeycomb structure in the STM images, whereas the motion among the three does the 1 × 1 structure. We have found that the electron states which effectively follow the Dirac equation in the freestanding silicene couple with the substrate Ag orbitals due to the bond formation, and shift downwards deep in the valence bands. This feature is common to all the stable or metastable silicene layer on the Ag(111) substrate.
How baryonic processes affect strong lensing properties of simulated galaxy clusters

The observed abundance of giant arcs produced by galaxy cluster lenses and the measured Einstein radii have presented a source of tension for Λ cold dark matter (ΛCDM), particularly at low redshifts (z ∼ 0.2). Previous cosmological tests for high-redshift clusters (z > 0.5) have suffered from small number statistics in the simulated sample and the implementation of baryonic physics is likely to affect the outcome. We analyse zoomed-in simulations of a fairly large sample of cluster-sized objects, with Mvir > 3 × 1014 h−1 M⊙, identified at z = 0.25 and 0.5, for a concordance ΛCDM cosmology. These simulations have been carried out by incrementally increasing the physics considered. We start with dark-matter-only simulations and then add gas hydrodynamics, with different treatments of baryonic processes: non-radiative cooling, radiative cooling with star formation and galactic winds powered by supernova explosions, and finally including the effect of active galactic nucleus (AGN) feedback. Our analysis of strong lensing properties is based on the computation of the cross-section for the formation of giant arcs and of the Einstein radii. We find that the addition of gas in non-radiative simulations does not change the strong lensing predictions significantly, but gas cooling and star formation together significantly increase the number of expected giant arcs and the Einstein radii, particularly for lower redshift clusters and lower source redshifts. Further inclusion of AGN feedback reduces the predicted strong lensing efficiencies such that the lensing probability distributions become closer to those obtained for simulations including only dark matter. Our results indicate that the inclusion of baryonic physics in simulations will not solve the arc-statistics problem at low redshifts, when the physical processes included provide a realistic description of cooling in the central regions of galaxy clusters. As outcomes of our analysis, we encourage the adoption of Einstein radii as a robust measure of strong lensing efficiency, and provide the ΛCDM predictions to be used for future comparisons with high-redshift cluster samples.
NPOI Measurements of Ten Stellar Oscillators

Using the Navy Precision Optical Interferometer, we measured the angular diameters of 10 stars that have previously measured solar-like oscillations. Our sample covered a range of evolutionary stages but focused on evolved subgiant and giant stars. We combined our angular diameters with Hipparcos parallaxes to determine the stars’ physical radii, and used photometry from the literature to calculate their bolometric fluxes, luminosities, and effective temperatures. We then used our results to test the scaling relations used by asteroseismology groups to calculate radii and found good agreement between the radii measured here and the radii predicted by stellar oscillation studies. The precision of the relations is not as well constrained for giant stars as it is for less evolved stars. Subject headings: visible: stars, stars: fundamental parameters, techniques: interferometric)
POLARIZED EXTENDED Lyα EMISSION FROM A z = 2.3 RADIO GALAXY

We present spatially resolved spectropolarimetric measurements of the 100 kpc scale gaseous environment of the z = 2.34 radio galaxy TXS 0211−122. The polarization level of the narrow Lyα emission is low centrally (P < 5%), but rises to P = 16.4% ± 4.6% in the eastern part of the nebula, indicating that the nebula is at least partly powered by the scattering of Lyα photons by H i. Not only is this the first detection of polarized Lyα around a radio-loud active galaxy, it is also the second detection to date for any kind of Lyα nebula. We also detect a pair of diametrically opposed UV continuum sources along the slit, at the outer edges of the Lyα nebula, which we suggest may be the limb of a dusty shell, related to the large-scale H i absorbers often associated with high-z radio galaxies.
IceCube PeV-EeV neutrinos and secret interactions of neutrinos

We show that the PeV neutrinos detected by IceCube put unique constraints on "secret" interactions of neutrinos with the cosmic neutrino background (C$\nu$B). The coupling must be $g <0.03$ for the mediating boson mass $m_{X} \lesssim 2$ MeV, $g/m_{X} < 5$ GeV$^{-1}$ for $m_{X} \gtrsim 20$ MeV, and $g/m_{X} < 0.07$ GeV$^{-1}$ in between. We also investigate the possibility that neutrino cascades degrade high-energy neutrinos to PeV energies by upgrading C$\nu$B where the energy flux of PeV neutrinos can coincide with the Waxman-Bahcall bound or the cosmogenic neutrino flux for protons, thanks to energy conservation. However a large coupling is required, which is disfavored by laboratory decay constraints. The suppression of PeV-EeV neutrinos is a testable prediction for the Askaryan Radio Array.
CMB power spectrum estimation using wavelets

Observations of the cosmic microwave background (CMB) provide increasingly accurate information about the structure of the Universe at the recombination epoch. Most of this information is encoded in the angular power spectrum of the CMB. The aim of this work is to propose a versatile and powerful method for spectral estimation on the sphere which can easily deal with nonstationary uncorrelated noise and multiple experiments with various specifications. In this paper, we use needlets (wavelets) on the sphere to construct natural and efficient spectral estimators for partially observed and beamed CMB with nonstationary noise. In the case of a single experiment, we compare this method with pseudo-C{sub l} methods. The performance of the needlet spectral estimators (NSE) compares very favorably to the best pseudo-C{sub l} estimators, over the whole multipole range. On simulations with a simple model (CMB+uncorrelated noise with known variance per pixel+mask), they perform uniformly better. Their distinctive ability to aggregate many different experiments, to control the propagation of errors, and to produce a single wideband error bar is highlighted. The needlet spectral estimator is a powerful, tunable tool which is very well suited to the angular power spectrum estimation of spherical data such as incomplete and noisymore » CMB maps. « less
Does it work? A scholastic epistemology perspective on evidence-based practice in social welfare

ABSTRACT Contemporary “knowledge” relies increasingly on probabilistic data. A key example is the “evidence” for the effectiveness of health and social welfare interventions. Such claims to “knowing” require an epistemological underpinning. This paper explores the concept of probabilistic knowledge, evidence and “proof” which underpin claims for the effectiveness of social welfare interventions from the perspective of scholastic epistemology. It provides a framework based on contingent events, establishing different levels of certitude and ways of increasing it, thanks to intellectual virtues such as prudence and art. Knowing the value of the data that form the basis for making decisions in social processes, we can construct directions for social policies. Greater methodological precision (that philosophy in its various traditions might offer) may be of service to attempts in social work to conceptualize questions of effectiveness and measurement of outcomes, given their probabilistic nature.
Detecting baryon acoustic oscillations by 3d weak lensing

We investigate the possibility of detecting baryon acoustic oscillation features in the cosmic matter distribution by 3d weak lensing. Baryon oscillations are inaccessible even to weak lensing tomography because of wide line-of-sight weighting functions and require a specialized approach via 3d shear estimates. We quantify the uncertainty of estimating the matter spectrum amplitude at the baryon oscillations wave vectors by a Fisher-matrix approach with a fixed cosmology and show in this way that future weak lensing surveys such as EUCLID and DES are able to pick up the first four wiggles, with EUCLID giving a better precision in the measurement. We also provide a detailed investigation of the correlation existing between errors and of their scaling behavior with respect to survey parameters such as median redshift, error on redshift, error on the galaxy shape measurement, sky coverage, and finally with respect to the number of wiggles one is trying to determine.
Pseudo-Media Disinformation Patterns: Polarised Discourse, Clickbait and Twisted Journalistic Mimicry

ABSTRACT Information disorder involves wide-ranging content that challenges democratic rules and social harmony. Pseudo-media that relies on conspiracy theories and misleading versions of the social reality contribute to feeding the disinformation ecosystem by reinforcing biased messages with expressive patterns and polarising practices. This article focuses on the content published (N = 1,396) by seven far-right wing Spanish pseudo-media. Based on qualitative and quantitative methods, it analyses headlines, types of text and sources, as well as the distortion strategies of journalistic conventions. Results show that the emotional component is expressed by means of polarised headlines that rely on clickbait to gain attention and build a particular jargon, exacerbated by disinformation and populist practices. The absolute dependence of conspicuous headlines is evidenced by the limited resources of pseudo-media, whose production lies in a mix of opinion text and the processing of online content. Plagiarism from mainstream—mainly conservative—media, social networks and website siblings fuel these outlets that play the role of the ambiguity, mimicking journalistic conventions and mocking them by means of disinformation practices, with a particular focus on reframing social issues, progressive policies and measures to manage the pandemic.
MULTILAYER FORMATION AND EVAPORATION OF DEUTERATED ICES IN PRESTELLAR AND PROTOSTELLAR CORES

Extremely large deuteration of several molecules has been observed toward prestellar cores and low-mass protostars for a decade. New observations performed toward low-mass protostars suggest that water presents a lower deuteration in the warm inner gas than in the cold external envelope. We coupled a gas–grain astrochemical model with a one-dimensional model of a collapsing core to properly follow the formation and the deuteration of interstellar ices as well as their subsequent evaporation in the low-mass protostellar envelopes with the aim of interpreting the spatial and temporal evolutions of their deuteration. The astrochemical model follows the formation and the evaporation of ices with a multilayer approach and also includes a state-of-the-art deuterated chemical network by taking the spin states of H2 and light ions into account. Because of their slow formation, interstellar ices are chemically heterogeneous and show an increase of their deuterium fractionation toward the surface. The differentiation of the deuteration in ices induces an evolution of the deuteration within protostellar envelopes. The warm inner region is poorly deuterated because it includes the whole molecular content of ices, while the deuteration predicted in the cold external envelope scales with the highly deuterated surface of ices. We are able to reproduce the observed evolution of water deuteration within protostellar envelopes, but we are still unable to predict the super-high deuteration observed for formaldehyde and methanol. Finally, the extension of this study to the deuteration of complex organics, important for the prebiotic chemistry, shows good agreement with the observations, suggesting that we can use the deuteration to retrace their mechanisms and their moments of formation.
Semiclassical OPE coefficients from 3D gravity

We present a closed form expression for the semiclassical OPE coefficients that are universal for all 2D CFTs with a "weak" light spectrum, by taking the semiclassical limit of the fusion kernel. We match this with a properly regularized and normalized bulk action evaluated on a geometry with three conical defects, analytically continued in the deficit angles beyond the range for which a metric with positive signature exists. The analytically continued geometry has a codimension-one coordinate singularity surrounding the heaviest conical defect. This singularity becomes a horizon after Wick rotating to Lorentzian signature, suggesting a connection between universality and the existence of a horizon.
Rapidly Star-forming Galaxies At High Redshifts

Herschel has opened new windows into studying the evolution of rapidly star-forming galaxies out to high redshifts. Today's massive starbursts are characterized by star formation rates (SFRs) of 100+ Mo/yr and display a chaotic morphology and nucleated star formation indicative of a major merger. At z~2, galaxies of similar mass and SFR are characterized by ordered rotation and distributed star formation. The emerging cold accretion paradigm provides an intuitive understanding for such differences. In it, halo accretion rates govern the supply of gas into star-forming regions, modulated by strong outflows. The high accretion rates at high-z drive more rapid star formation, while also making disks thicker and clumpier; the clumps are expected to be short-lived in the presence of strong galactic outflows as observed. Hence equivalently rapid star-formers at high redshift are not analogous to local merger-driven starbursts, but rather to local disks with highly enhanced accretion rates.