Miracle-dz/UniFAR-FTUs huggingface dataset:
ABSOLUTE PROPERTIES OF THE ECLIPSING BINARY SYSTEM AQ SERPENTIS: A STRINGENT TEST OF CONVECTIVE CORE OVERSHOOTING IN STELLAR EVOLUTION MODELS

We report differential photometric observations and radial-velocity measurements of the detached, 1.69 day period, double-lined eclipsing binary AQ Ser. Accurate masses and radii for the components are determined to better than 1.8% and 1.1%, respectively, and are M1 = 1.417 ± 0.021 M☉, M2 = 1.346 ± 0.024 M☉, R1 = 2.451 ± 0.027 R☉, and R2 = 2.281 ± 0.014 R☉. The temperatures are 6340 ± 100 K (spectral type F6) and 6430 ± 100 K (F5), respectively. Both stars are considerably evolved, such that predictions from stellar evolution theory are particularly sensitive to the degree of extra mixing above the convective core (overshoot). The component masses are different enough to exclude a location in the H-R diagram past the point of central hydrogen exhaustion, which implies the need for extra mixing. Moreover, we find that current main-sequence models are unable to match the observed properties at a single age even when allowing the unknown metallicity, mixing length parameter, and convective overshooting parameter to vary freely and independently for the two components. The age of the more massive star appears systematically younger. AQ Ser and other similarly evolved eclipsing binaries showing the same discrepancy highlight an outstanding and largely overlooked problem with the description of overshooting in current stellar theory.
THE ELECTRICAL CURRENT DENSITY VECTOR IN THE INNER PENUMBRA OF A SUNSPOT

We determine the entire electrical current density vector in a geometrical three-dimensional volume of the inner penumbra of a sunspot from an inversion of spectropolarimetric data obtained with Hinode/SP. Significant currents are seen to wrap around the hotter, more elevated regions with lower and more horizontal magnetic fields that harbor strong upflows and radial outflows (the intraspines). The horizontal component of the current density vector is 3–4 times larger than the vertical; nearly all previous studies only obtain the vertical component Jz, thus strongly underestimating the current density. The current density and the magnetic field form an angle of about 20°. The plasma β at the 0 km level is larger than 1 in the intraspines and is one order of magnitude lower in the background component of the penumbra (spines). At the 200 km level, the plasma β is below 0.3, nearly everywhere. The plasma β surface as well as the surface optical depth unity is very corrugated. At the borders of intraspines and inside, is not force-free at deeper layers and nearly force-free at the top layers. The magnetic field of the spines is close to being potential everywhere. The dissipated ohmic energy is five orders of magnitudes smaller than the solar energy flux and thus negligible for the energy balance of the penumbra.
Imitating intrinsic alignments: a bias to the CMB lensing-galaxy shape cross-correlation power spectrum induced by the large-scale structure bispectrum

Cross-correlating the lensing signals of galaxies and comic microwave background (CMB) fluctuations is expected to provide valuable cosmological information. In particular it may help tighten constraints on parameters describing the properties of intrinsically aligned galaxies at high redshift. To access the information conveyed by the cross-correlation signal its accurate theoretical description is required. We compute the bias to CMB lensing-galaxy shape cross-correlation measurements induced by nonlinear structure growth. Using tree-level perturbation theory for the large-scale structure bispectrum we find that the bias is negative on most angular scales, therefore mimicking the signal of intrinsic alignments. Combining Euclid-like galaxy lensing data with a CMB experiment comparable to the Planck satellite mission the bias becomes significant only on smallest scales ($\ell\gtrsim 2500$). For improved CMB observations, however, the corrections amount to 10-15 per cent of the CMB lensing-intrinsic alignment signal over a wide multipole range ($10 \lesssim \ell \lesssim 2000$). Accordingly the power spectrum bias, if uncorrected, translates into $2\sigma$ and $3\sigma$ errors in the determination of the intrinsic alignment amplitude in case of CMB stage III and stage IV experiments, respectively.
Crystal structure search and electronic properties of alkali-doped phenanthrene and picene

Alkali doped aromatic compounds have shown evidence of metallic and superconducting phases whose precise nature is still mysterious. In potassium and rubidium doped phenanthrene, superconducting temperatures around 5 K have been detected, but such basic elements as the stoichiometry, crystal structure, and electronic bands are still speculative. We seek to predict the crystal structure of M3-phenanthrene (M = K, Rb) using ab-initio evolutionary simulation in conjunction with density functional theory (DFT), and find metal but also insulator phases with distinct structures. The original P21 herringbone structure of the pristine molecular crystal is generally abandoned in favor of different packing and chemical motifs. The metallic phases are frankly ionic with three electrons acquired by each molecule. In the nonmagnetic insulating phases the alkalis coalesce reducing the donated charge from three to two per phenanthrene molecule. A similar search for K3-picene yields an old and a new structure, with unlike potassium positions and different electronic bands, but both metallic retaining the face-to-edge herringbone structure and the P21 symmetry of pristine picene. Both the new K3-picene and the best metallic M3-phenanthrene are further found to undergo a spontaneous transition from metal to antiferromagnetic insulator when spin polarization is allowed, a transition which is not necessarily real, but which underlines the necessity to include correlations beyond DFT. Features of the metallic phases that may be relevant to phonon-driven superconductivity are underlined.
Vacuum entanglement enhancement by a weak gravitational field

such as that caused by a planet, can enhance the extraction of entanglement from the vacuum. This article is organized as follows. In Sec. II we review the extraction of entanglement with Unruh-DeWitt detectors in Minkowski space-time. In Sec. III we review the Newtonian limit of general relativity and in Sec. IV we look at Unruh-DeWitt detectors in the presence of weak gravity. Then, in Sec. V we compute the rst order correction to the propagator on the perturbed background. In Sec. VI we calculate explicitly the entanglement between the two detectors near a spherically symmetric star. In the last section, we propose extensions. We work with the natural units ~ = c = G = 1 and the Minkowski metric = diag( 1; 1; 1; 1). We denote the coordinate time by x 0 = t while the proper time is denoted by . Wherever necessary to avoid ambiguity we will denote operators O or statesj i which live in the Hilbert spaceH (j) of the j’th subsystem by a superscript (j), for example, O (j) andj (j) i. Orders in perturbation theory will be denoted by a subscript (j), as in, e.g., P = P(0) +P(1) +O( 2 ). We work in the interaction picture.
The reversal of the SF–density relation in a massive, X-ray-selected galaxy cluster at z = 1.58: results from Herschel

Dusty, star-forming galaxies have a critical role in the formation and evolution of massive galaxies in the Universe. Using deep far-infrared imaging in the range 100-500um obtained with the Herschel telescope, we investigate the dust-obscured star formation in the galaxy cluster XDCP J0044.0-2033 at z=1.58, the most massive cluster at z >1.5, with a measured mass M200= 4.7x10$^{14}$ Msun. We perform an analysis of the spectral energy distributions (SEDs) of 12 cluster members (5 spectroscopically confirmed) detected with >3$\sigma$ significance in the PACS maps, all ULIRGs. The individual star formation rates (SFRs) lie in the range 155-824 Ms/yr, with dust temperatures of 24$\pm$35 K. We measure a strikingly high amount of star formation (SF) in the cluster core, SFR ( 1875$\pm$158 Ms/yr, 4x higher than the amount of star formation in the cluster outskirts. This scenario is unprecedented in a galaxy cluster, showing for the first time a reversal of the SF-density relation at z~1.6 in a massive cluster.
COMMERCIAL LAYING HEN PRODUCTION AND EGG VALUE CHAIN MAPPING IN NORTHERN ETH

Background: In Ethiopia, commercial farms have increased in farm size, and the majority of the large-scale poultry farms are concentrated around Addis Ababa the capital city of Ethiopia. Objective: To assess poultry production, map value chains and identify major production challenges in Northern Ethiopia. Methodology: A multistage sampling technique along with a proportionate sample size determination method was used to fix the sample size. Accordingly, 147, 109 and 64 poultry producers were selected from semi-intensive, small-scale, and medium-scale farms, respectively. Nine focus group discussions comprising relevant stakeholders were conducted. Result: The earlier age at first egg-laying in weeks was reported as 16.7 ± 0.93 in the medium-scale production system. A high laying percentage of 85.47 ± 5.01 was recorded in the medium-scale and the highest mortality 23.5 ± 8.8 was in semi-intensive. The price of eggs varied by about +38% in November 2019/2020 and negatively changed price by -22% in May 2019/2020. In a ranking exercise, feed cost, feed quality, product marketing, disease, predator, and lack of information and training were ranked top five. Further risk factors were ranked, accordingly, lack of vaccine, poor biosecurity measures, and management were ranked as major causes. Implication: The government and private sector should promote improving the feeding habit of the community and improve the management practice. Conclusion: The high price of feed ingredients, limited access to veterinary services, poor market linkages in the value chain, poor feeding habits, and poor extension services aggravated by a lack of awareness of producers were the most important challenges affecting commercial production.
WEIGHING THE GALACTIC DARK MATTER HALO: A LOWER MASS LIMIT FROM THE FASTEST HALO STAR KNOWN

The mass of the Galactic dark matter halo is under vivid discussion. A recent study by Xue et al. revised the Galactic halo mass downward by a factor of ∼2 relative to previous work, based on the line-of-sight velocity distribution of ∼2400 blue horizontal-branch (BHB) halo stars. The observations were interpreted with a statistical approach using cosmological galaxy formation simulations, as only four of the six-dimensional phase-space coordinates were determined. Here we concentrate on a close investigation of the stars with the highest negative radial velocity from that sample. For one star, SDSSJ153935.67+023909.8 (J1539+0239 for short), we succeed in measuring a significant proper motion, i.e., full phase-space information is obtained. We confirm the star to be a Population II BHB star from an independent quantitative analysis of the Sloan Digital Sky Survey (SDSS) spectrum—providing the first non-LTE (NLTE) study of any halo BHB star—and reconstruct its three-dimensional trajectory in the Galactic potential. J1539+0239 turns out to be the fastest halo star known to date, with a Galactic rest-frame velocity of 694+300−221 km s-1 (full uncertainty range from Monte Carlo error propagation) at its current position. The extreme kinematics of the star allows a significant lower limit to be put on the halo mass in order to keep it bound, of Mhalo ⩾ 1.7+2.3−1.1 × 1012 M☉. We conclude that the Xue et al. results tend to underestimate the true halo mass as their most likely mass value is consistent with our analysis only at a level of 4%. However, our result confirms other studies that make use of the full phase-space information.
Testing dark energy models with $H(z)$ data

$Om(z)$ is a diagnostic approach to distinguish dark energy models. However, there are few articles to discuss what is the distinguishing criterion. In this paper, firstly we smooth the latest observational $H(z)$ data using a model-independent method -- Gaussian processes, and then reconstruct the $Om(z)$ and its fist order derivative $\mathcal{L}^{(1)}_m$. Such reconstructions not only could be the distinguishing criteria, but also could be used to estimate the authenticity of models. We choose some popular models to study, such as $\Lambda$CDM, generalized Chaplygin gas (GCG) model, Chevallier-Polarski-Linder (CPL) parametrization and Jassal-Bagla-Padmanabhan (JBP) parametrization. We plot the trajectories of $Om(z)$ and $\mathcal{L}^{(1)}_m$ with $1 \sigma$ confidence level of these models, and compare them to the reconstruction from $H(z)$ data set. The result indicates that the $H(z)$ data does not favor the CPL and JBP models at $1 \sigma$ confidence level. Strangely, in high redshift range, the reconstructed $\mathcal{L}^{(1)}_m$ has a tendency of deviation from theoretical value, which demonstrates these models are disagreeable with high redshift $H(z)$ data. This result supports the conclusions of Sahni et al. \citep{sahni2014model} and Ding et al. \citep{ding2015there} that the $\Lambda$CDM may not be the best description of our universe.
The orbital period–mass ratio relation of wide sdB+MS binaries and its application to the stability of RLOF

Wide binaries with hot subdwarf-B (sdB) primaries and main sequence companions are thought to form only through stable Roche lobe overflow (RLOF) of the sdB progenitor near the tip of the red giant branch (RGB). We present the orbital parameters of eleven new long period composite sdB binaries based on spectroscopic observations obtained with the UVES, FEROS and CHIRON spectrographs. Using all wide sdB binaries with known orbital parameters, 23 systems, the observed period distribution is found to match very well with theoretical predictions. A second result is the strong correlation between the orbital period (P) and the mass ratio (q) in the observed wide sdB binaries. In the P-q plane two distinct groups emerge, with the main group (18 systems) showing a strong correlation of lower mass ratios at longer orbital periods. The second group are systems that are thought to be formed from higher mass progenitors. Based on theoretical models, a correlation between the initial mass ratio at the start of RLOF and core mass of the sdB progenitor is found, which defines a mass-ratio range at which RLOF is stable on the RGB.
Non-steady-state long-term evolution of supermassive black hole binaries surrounded by accretion discs

Supermassive black holes (SMBHs) pair and form bound binaries after their host galaxies merge. In a gas-rich merger, accretion discs are expected to form around the binary and its components. These discs control the binary orbital evolution until the system is compact enough for gravitational waves to drive the SMBHs to coalescence. In this work, we implemented a time-dependent 1D model to follow the long-term evolution of the coupled binary + discs system, from a separation of 10^5 down to 20 Schwarzschild radii. We run different models changing the system parameters, including the binary mass ratio q \leq 0.3 and a factor {\gamma} that controls the inflow across the gap created by the secondary. We find that our implementation yields higher residual masses and longer binary residence times than previous studies. Our main conclusion is the non-steady-state nature of the evolution of the system: the properties the disc had when the binary was still at large separations influence its whole evolution. To recover steady state, the binary residence time would have to be much longer than the inflow time-scale of the disc throughout their entire history, which in general is not satisfied.
DISCOVERY OF A 112 ms X-RAY PULSAR IN PUPPIS A: FURTHER EVIDENCE OF NEUTRON STARS WEAKLY MAGNETIZED AT BIRTH

We report the discovery of 112 ms X-ray pulsations from RX J0822−4300, the compact central object (CCO) in the supernova remnant (SNR) Puppis A, in two archival Newton X-Ray Multi-Mirror Mission observations taken in 2001. The sinusoidal light curve has a pulsed fraction of 11% with an abrupt 180° change in phase at 1.2 keV. The observed phase shift and modulation are likely the result of emission from opposing thermal hot spots of distinct temperatures. Phase-resolved spectra reveal an emission feature at Eline = 0.8 keV associated with the cooler region, possibly due to an electron cyclotron resonance effect similar to that seen in the spectrum of the CCO pulsar 1E 1207.4−5209. No change in the spin period of PSR J0821−4300 is detected in seven months, with a 2σ upper limit on the period derivative of . This implies limits on the spin-down energy loss rate of erg s−1, the surface magnetic dipole field strength Bs < 9.8 × 1011 G, and the spin-down age τc > 220 kyr. The latter is much longer than the SNR age, indicating that PSR J0821−4300 was born spinning near its present period. Its properties are remarkably similar to those of the two other known CCO pulsars, demonstrating the existence of a class of neutron stars born with weak magnetic fields related to a slow original spin. These results are also of importance in understanding the extreme transverse velocity of PSR J0821−4300, favoring the hydrodynamic instability mechanism in the supernova explosion.
Near-Solar-Circle Method for Determination of the Galactic Constants

We propose a method to determine the galactic constants R_0 (distance to the Galactic Center) and V_0 (rotation velocity of the Sun) from measurements of distances, radial velocities and proper motions of objects near the solar circle. This is a modification of the solar-circle method to a more practical observational method. We apply the method to determine R_0 using data from the literature with known distances and radial velocities, and obtain R_0 = 7.54 +/- 0.77 kpc.
Electronic structure of FeS

Here we report the electronic structure of FeS, a recently identified iron-based superconductor. Our high-resolution angle-resolved photoemission spectroscopy studies show two hole-like ($\alpha$ and $\beta$) and two electron-like ($\eta$ and $\delta$) Fermi pockets around the Brillouin zone center and corner, respectively, all of which exhibit moderate dispersion along $k_z$. However, a third hole-like band ($\gamma$) is not observed, which is expected around the zone center from band calculations and is common in iron-based superconductors. Since this band has the highest renormalization factor and is known to be the most vulnerable to defects, its absence in our data is likely due to defect scattering --- and yet superconductivity can exist without coherent quasiparticles in the $\gamma$ band. This may help resolve the current controversy on the superconducting gap structure of FeS. Moreover, by comparing the $\beta$ bandwidths of various iron chalcogenides, including FeS, FeSe$_{1-x}$S$_x$, FeSe, and FeSe$_{1-x}$ Te$_x$, we find that the $\beta$ bandwidth of FeS is the broadest. However, the band renormalization factor of FeS is still quite large, when compared with the band calculations, which indicates sizable electron correlations. This explains why the unconventional superconductivity can persist over such a broad range of isovalent substitution in FeSe$_{1-x}$Te$_{x}$ and FeSe$_{1-x}$S$_{x}$.
Impact of short-range order on transport properties of the two-dimensional metal PdCrO$_2$

We study the Hall and Nernst effects across the antiferromagnetic transition that reconstructs the quasi-2D Fermi surface of the metallic local moment antiferromagnet PdCrO$_2$. We show that non- monotonic temperature dependence in the Hall effect and a sign change in the Nernst effect above the ordering temperature cannot be understood within a simple single-band transport model. The inclusion of coherent scattering by critical antiferromagnetic fluctuations can qualitatively account for these features in the transport coefficients. We discuss the implications of this for the pseudogap phase of the cuprate superconductors, which have a similar Fermi surface and where the same transport signatures are observed.
Gender Differences of University Students in the Online Teaching Quality and Psychological Profile during the COVID-19 Pandemic

With the arrival of COVID-19, educational systems have had to adapt to the social and health situation immediately. This led to the appearance of the asynchronous teaching model. Throughout the pandemic, at the educational level, we can distinguish three phases, eminently online, hybrid, and finally, face-to-face. However, the perception of educational quality in these three educational moments, taking into account the psychometric profile and gender, has not been studied. Thus, 1093 university students from Ibero-American countries were analyzed. Through a questionnaire, demographic, academic, and psychological variables were analyzed at three moments during the evolution of the pandemic. Data suggest that, during the lockdown phase, while teaching was eminently online, students presented higher levels of stress and higher difficulty of learning; class attendance, convenience, preferred method of learning, grading score, and motivation were lower, compared to other phases of teaching (hybrid and face-to-face). During this period, females presented higher stress levels than males, as well as higher levels of anxiety and loneliness, without gender differences among the other studied variables. During the hybrid and face-to-face phases, male students presented higher values in the results of difficulty learning and demanding activities. No differences were seen regarding motivation, synchronous class attendance, learning level, grades, convenience, or preferred learning method. The results from the present study suggest that, despite the effect of the pandemic on mental health, asynchronous education is postulated as an effective teaching–learning alternative. Yet, a special focus should be given to female students.
CONTRIBUTION OF THE ACCRETION DISK, HOT CORONA, AND OBSCURING TORUS TO THE LUMINOSITY OF SEYFERT GALAXIES: INTEGRAL AND SPITZER OBSERVATIONS

We estimate the relative contributions of the supermassive black hole (SMBH) accretion disk, corona, and obscuring torus to the bolometric luminosity of Seyfert galaxies, using Spitzer mid-infrared (MIR) observations of a complete sample of 68 nearby active galactic nuclei (AGNs) from the INTEGRAL all-sky hard X-ray (HX) survey. This is the first HX-selected (above 15 keV) sample of AGNs with complementary high angular resolution, high signal-to-noise, MIR data. Correcting for the host galaxy contribution, we find a correlation between HX and MIR luminosities: L15 μm∝L0.74 ± 0.06HX. Assuming that the observed MIR emission is radiation from an accretion disk reprocessed in a surrounding dusty torus that subtends a solid angle decreasing with increasing luminosity (as inferred from the declining fraction of obscured AGNs), the intrinsic disk luminosity, LDisk, is approximately proportional to the luminosity of the corona in the 2–300 keV energy band, LCorona, with the LDisk/LCorona ratio varying by a factor of 2.1 around a mean value of 1.6. This ratio is a factor of ∼2 smaller than for typical quasars producing the cosmic X-ray background. Therefore, over three orders of magnitude in luminosity, HX radiation carries a large, and roughly comparable, fraction of the bolometric output of AGNs. We estimate the cumulative bolometric luminosity density of local AGNs at ∼(1–3) × 1040 erg s−1 Mpc−3. Finally, the Compton temperature ranges between kTc ≈ 2 and ≈6 keV for nearby AGNs, compared to kTc ≈ 2 keV for typical quasars, confirming that radiative heating of interstellar gas can play an important role in regulating SMBH growth.