Miracle-dz/UniFAR-FTUs huggingface dataset:
POSSIBLE CONSTRAINTS ON EXOPLANET MAGNETIC FIELD STRENGTHS FROM PLANET–STAR INTERACTION

A small percentage of normal stars harbor giant planets that orbit within a few tenths of an astronomical unit. At such distances, the potential exists for significant tidal and magnetic field interaction resulting in energy dissipation that may manifest as changes within the stellar corona. We examine the X-ray emission of stars hosting planets and find a positive correlation between X-ray luminosity and the projected mass of the most closely orbiting exoplanets. We investigate possible systematics and observational biases that could mimic or confuse this correlation but find no strong evidence for any, especially for planets more massive than ∼0.1 MJ. Luminosities and upper limits are consistent with the interpretation that there is a lower floor to stellar X-ray emission dependent on close-in planetary mass. Under the hypothesis that this is a consequence of planet–star magnetic field interaction, and energy dissipation, we estimate a possible field strength increase of a factor of ∼8 between planets of 1 and 10 MJ. Intriguingly, this is consistent with recent geodynamo scaling law predictions. The high-energy photon emission of planet–star systems may therefore provide unique access to the detailed magnetic, and hence geodynamic, properties of exoplanets.
Bar-driven evolution and quenching of spiral galaxies in cosmological simulations

We analyse the output of the hi-res cosmological “zoom-in” hydrodynamical simulation ErisBH to study self-consistently the formation of a strong stellar bar in a Milky Way-type galaxy and its effect on the galactic structure as well as on the central gas distribution and star formation. The simulation includes radiative cooling, star formation, SN feedback and a central massive black hole wich is undergoing gas accretion and is heating the surroundings via thermal AGN feedback. A large central region in the ErisBH disk becomes bar-unstable after z ∼ 1.4, but a clear bar-like structure starts to grow significantly only after z ≃ 0.4, possibly triggered by the interaction with a massive satellite. At z ≃ 0.1 the bar stabilizes and reaches its maximum radial extent of l ≈ 2.2 kpc. As the bar grows, it becomes prone to buckling instability, which we quantify based on the anisotropy of the stellar velocity dispersion. The actual buckling event is observable at z ≃ 0.1, resulting in the formation of a boxy-peanut bulge clearly discernible in the edge-on view of the galaxy at z = 0. The bar in ErisBH does not dissolve during the formation of the bulge but it is long-lived and is strongly non-axisymmetric down to the resolution limit of ∼ 100 pc at z = 0. During its early growth, the bar exerts a strong torque on the gas within its extent and drives gas inflows that enhance the nuclear star formation on sub-kpc scales. Later on, as the bar reaches its maximum length and strength, the infalling gas is nearly all consumed into stars and, to a lesser extent, accreted onto the central black hole, leaving behind a gasdepleted region within the central ∼ 2 kpc. Observations would more likely identify a prominent, large-scale bar at the stage when the galactic central region has already been quenched. Bar-driven quenching may play an important role in disk-dominated galaxies at all redshift. AGN feedback is instrumental in this scenario not because it directly leads to quenching, but because it promotes a strong bar by maintaining a flat rotation curve, suppressing the density of baryons within the central kpc in the early stages of the formation of the galaxy.
Variability survey in the young open cluster IC 1805

The variability survey in the young open cluster IC 1805 is a part of the ongoing program of searching for early-type variable stars in open clusters of the northern sky conducted in Wroclaw (see Jerzykiewicz et al. 2011 and references therein). We are particularly interested in pulsating stars such as beta Cephei and SPB. These stars are very promising targets for asteroseismology. In particular, open clusters rich in these variables can be used for so called ensemble asteroseismology (Saesen et al. 2010).
Comparison of Eddy Current Coupling Topologies for High Efficiency Mechanical Power Transmission

The article is an investigation into permanent magnet eddy current couplings for high efficiency power transmission. Through extensive simulation studies, the performance of radial- and axial-field topologies, employing squirrel cage and conducting sheets, are compared in terms of torque transmission density and efficiency of power transmission. It is shown, that although using a conducting sheet (as it is often the case) results in higher torque transmission density, employing a squirrel cage is more suitable for high efficiency power transmission. A prototype of the proposed radial-field single sided permanent magnet eddy current coupling employing a copper squirrel cage is developed and tested, and a good agreement between measurements and predictions is demonstrated.
XMM-Newton observation of SN 1993J in M81

In April 2001 SN 1993J was observed with both the PN and MOS cameras of the XMM-Newton observatory, resulting in about $7\times 10^4~$s of acceptable observation time. Fit results with both the PN and MOS2 camera spectra studying different spectral models are presented. The spectra are best fitted in the energy range between 0.3 and ~10 keV by a 2-component thermal model with temperatures of $kT_1 = 0.34\pm 0.04$ keV and $kT_2 = 6.54\pm 4$ keV, adopting ionization equilibrium. A fit with a shock model also provides acceptable results. Combining the XMM-Newton data with former X-ray observations of the supernova, we discuss the general trend of $L_{\rm x}\propto t^{-0.30}$ and the bump of the X-ray light curve as well as former and recent spectral results in the light of the standard SN model as first proposed by Chevalier in 1982.
THE FORMATION AND DISINTEGRATION OF MAGNETIC BRIGHT POINTS OBSERVED BY SUNRISE/IMaX

The evolution of the physical parameters of magnetic bright points (MBPs) located in the quiet Sun (mainly in the interwork) during their lifetime is studied. First, we concentrate on the detailed description of the magnetic field evolution of three MBPs. This reveals that individual features follow different, generally complex, and rather dynamic scenarios of evolution. Next, we apply statistical methods on roughly 200 observed MBP evolutionary tracks. MBPs are found to be formed by the strengthening of an equipartition field patch, which initially exhibits a moderate downflow. During the evolution, strong downdrafts with an average velocity of 2.4 km s−1 set in. These flows, taken together with the concurrent strengthening of the field, suggest that we are witnessing the occurrence of convective collapses in these features, although only 30% of them reach kG field strengths. This fraction might turn out to be larger when the new 4 m class solar telescopes are operational as observations of MBPs with current state of the art instrumentation could still be suffering from resolution limitations. Finally, when the bright point disappears (although the magnetic field often continues to exist) the magnetic field strength has dropped to the equipartition level and is generally somewhat weaker than at the beginning of the MBP's evolution. Also, only relatively weak downflows are found on average at this stage of the evolution. Only 16% of the features display upflows at the time that the field weakens, or the MBP disappears. This speaks either for a very fast evolving dynamic process at the end of the lifetime, which could not be temporally resolved, or against strong upflows as the cause of the weakening of the field of these magnetic elements, as has been proposed based on simulation results. It is noteworthy that in about 10% of the cases, we observe in the vicinity of the downflows small-scale strong (exceeding 2 km s−1) intergranular upflows related spatially and temporally to these downflows. The paper is complemented by a detailed discussion of aspects regarding the applied methods, the complementary literature, and in depth analysis of parameters like magnetic field strength and velocity distributions. An important difference to magnetic elements and associated bright structures in active region plage is that most of the quiet Sun bright points display significant downflows over a large fraction of their lifetime (i.e., in more than 46% of time instances/measurements they show downflows exceeding 1 km s−1).
BLACK HOLE FORAGING: FEEDBACK DRIVES FEEDING

We suggest a new picture of supermassive black hole (SMBH) growth in galaxy centers. Momentum-driven feedback from an accreting hole gives significant orbital energy, but little angular momentum to the surrounding gas. Once central accretion drops, the feedback weakens and swept-up gas falls back toward the SMBH on near-parabolic orbits. These intersect near the black hole with partially opposed specific angular momenta, causing further infall and ultimately the formation of a small-scale accretion disk. The feeding rates into the disk typically exceed Eddington by factors of a few, growing the hole on the Salpeter timescale and stimulating further feedback. Natural consequences of this picture include (1) the formation and maintenance of a roughly toroidal distribution of obscuring matter near the hole; (2) random orientations of successive accretion disk episodes; (3) the possibility of rapid SMBH growth; (4) tidal disruption of stars and close binaries formed from infalling gas, resulting in visible flares and ejection of hypervelocity stars; (5) super-solar abundances of the matter accreting on to the SMBH; and (6) a lower central dark-matter density, and hence annihilation signal, than adiabatic SMBH growth implies. We also suggest a simple subgrid recipe for implementing this process in numerical simulations.
Einsteinian cubic gravity

We drastically simplify the problem of linearizing a general higher-order theory of gravity. We reduce it to the evaluation of its Lagrangian on a particular Riemann tensor depending on two parameters, and the computation of two derivatives with respect to one of those parameters. We use our method to construct a D-dimensional cubic theory of gravity which satisfies the following properties: 1) it shares the spectrum of Einstein gravity, i.e., it only propagates a transverse and massless graviton on a maximally symmetric background; 2) the relative coefficients of the different curvature invariants involved are the same in all dimensions; 3) it is neither trivial nor topological in four dimensions. Up to cubic order in curvature, the only previously known theories satisfying the first two requirements are the Lovelock ones: Einstein gravity, Gauss-Bonnet and cubic-Lovelock. Of course, the last two theories fail to satisfy requirement 3 as they are, respectively, topological and trivial in four dimensions. We show that, up to cubic order, there exists only one additional theory satisfying requirements 1 and 2. Interestingly, this theory is, along with Einstein gravity, the only theory which also satisfies 3.
Parametric Modeling of the 3.6-8 μm Color Distributions of Galaxies in the SWIRE Survey

We fit a parametric model comprising a mixture of multidimensional Gaussian functions to the 3.6-8 μm color and optical photometric redshift distribution of galaxy populations in the ELAIS-N1 and Lockman Fields of the Spitzer Wide-Area Infrared Extragalactic (SWIRE) Legacy survey. For 16,698 sources in ELAIS-N1 we find our data are best modeled (in the sense of the Bayesian information criterion) by the sum of four Gaussian distributions or modes (Ca, Cb, Cc, and Cd). We compare the fit of our empirical model with predictions from existing semianalytic and phenomenological models. We infer that our empirical model provides a better description of the mid-infrared color distribution of the SWIRE survey than these existing models. This color distribution test is thus a powerful model discriminator and is entirely complementary to comparisons of number counts. We use our model to provide a galaxy classification scheme and explore the nature of the galaxies in the different modes of the model. Population Ca is found to consist of dusty star-forming systems such as ultraluminous infrared galaxies, over a broad redshift range. Low-redshift late-type spiral galaxies are found in population Cb, in which polycyclic aromatic hydrocarbon emission dominates at 8 μm, making these sources very red in longer wavelength Infrared Array Camera (IRAC) colors. Population Cc consists of dusty starburst systems with high levels of star formation activity at intermediate redshifts. Low-redshift early-type spiral and elliptical galaxies are found to dominate population Cd. We thus find a greater variety of galaxy types than one can with optical photometry alone. Finally, we develop a new technique to identify unusual objects and find a selection of outliers with very red IRAC colors. These objects are not detected in the optical but have very strong detections in the mid-infrared. These sources are modeled as dust-enshrouded, strongly obscured active galactic nuclei (AGNs), for which the high mid-infrared emission may be attributed to either dust heated by the AGNs or substantial star formation. These sources have zph ∼ 2-4, making them incredibly infrared-luminous, with LIR ∼ 1012.6-1014.1 L⊙.
Transient dynamics of perturbations in astrophysical disks

We review some aspects of a major unsolved problem in understanding astrophysical (in particular, accretion) disks: whether the disk interiors can be effectively viscous in spite of the absence of magnetorotational instability. A rotational homogeneous inviscid flow with a Keplerian angular velocity profile is spectrally stable, making the transient growth of perturbations a candidate mechanism for energy transfer from regular motion to perturbations. Transient perturbations differ qualitatively from perturbation modes and can grow substantially in shear flows due to the nonnormality of their dynamical evolution operator. Because the eigenvectors of this operator, also known as perturbation modes, are not pairwise orthogonal, they can mutually interfere, resulting in the transient growth of their linear combinations. Physically, a growing transient perturbation is a leading spiral whose branches are shrunk as a result of the differential rotation of the flow. We discuss in detail the transient growth of vortex shearing harmonics in the spatially local limit, as well as methods for identifying the optimal (fastest growth) perturbations. Special attention is given to obtaining such solutions variationally by integrating the respective direct and adjoint equations forward and backward in time. The presentation is intended for experts new to the subject.
Single-feed circularly polarized rectangular dielectric resonator antenna coupled with dual mode slot-line square ring resonator

A novel single-feed circularly polarized (CP) rectangular dielectric resonator antenna (RDRA) based on dual mode slot-line square ring resonator (SSRR) is proposed. The dual mode SSRR loaded with a perturbation is used to excite the TE111 mode and TE111 mode of rectangular dielectric resonator (RDR) simultaneously. By selecting a suitable size of the perturbation, the orthogonal degenerate modes of the SSRR are obtained. Accordingly, the CP radiation pattern of the proposed RDRA is generated from the orthogonal degenerate modes of the SSRR. A prototype is designed and measured. The RDRA has a wide impedance bandwidth of 14.28% (3.16-3.66GHz). The achieved 3 dB Axial Ratio (AR) bandwidth of the RDRA is about 100MHz at 3.5GHz. With the advantages of compact structure, CP performance and easy fabrication, this structure can be a good candidate for 5G communication system in the future. key words: Circularly polarization, dielectric resonator antenna, dual mode, slot-line ring resonator Classification: Microwave and millimeter wave devices, circuits, and hardware
All-Optical Format Conversion for Star-8QAM Signals Based on Nonlinear Effects in Elastic Optical Networks

An all-optical format conversion (AOFC) scheme for star-octal quadrature amplitude modulation (star-8QAM) signals is proposed and numerically simulated based on nonlinear effects in the high nonlinear fiber (HNLF). In the first stage AOFC processing, the input 30 Gbit/s star-8QAM signal is firstly de-aggregated into one 20 Gbit/s quadrature phase shift keying (QPSK) signal and one 10 Gbit/s typical on-off keying (OOK) signal by deploying the self-phase modulation (SPM), cross-phase modulation (XPM) and parametric amplification (PA) effects. In the second stage AOFC processing, the 20 Gbit/s QPSK signal and the 10 Gbit/s typical OOK signal are aggregated into one 30 Gbit/s star-8QAM signal again by utilizing the XPM and PA effects. Moreover, the amplitude ratio (AR) between the outer ring and inner rings of the aggregated star-8QAM signal can be adjusted flexibly by changing the QPSK and OOK signals power. Other octal modulation formats can also be generated through changing the QPSK and OOK signals power, including the rectangular 8QAM signals, $\pi$/4-8QAM signals and 8-ary phase shift keying (8PSK) signals. Error vector magnitude (EVM) and bit error ratio (BER) for star-8QAM signals before and after AOFC are measured to analyse the scheme performance. The AOFC scheme provides the flexibility to adopt the appreciate modulation formats at the optical nodes to connect different optical networks.
Invariant Cubature Kalman Filtering-Based Visual-Inertial Odometry for Robot Pose Estimation

To maintain mechanistic stability while tracking the designated walking route, a robot must be cognizant of employed posture. Generally, visual-inertial odometer (VIO) is utilized for robot state estimation; however, the traditional cubature Kalman filter VIO (CKF-VIO) cannot transfer rotational uncertainty and compensate for the system’s processing error. To effectively improve the accuracy and stability of robot rigid body pose estimation, this paper proposes a matrix Lie group representation-based CKF framework which characterizes the uncertainty prompting in robotic motion while eliminating the VIO system internalization errors. The robot state, consisting of inertial measurement unit (IMU) pose, velocity, and 3-D landmarks’ positions, is deemed to be a single element of a high-dimensional Lie group SE2+p (3), while the accelerometers’ and gyrometers’ biases are appended to the state and estimated as well. The algorithm is validated by simulations with Monte Carlo and experiment. Results show that the CKF-VIO with a high-dimensional Lie group can improve the accuracy and consistency of robot pose estimation.
ARE DISAPPEARING DWARFS JUST LYING LOW

Recent redshift surveys have shown that the excess galaxies seen in faint galaxy number counts (above those expected given the local galaxy luminosity function) are not evolved giants at high redshifts, but low to moderate luminosity objects at more modest redshifts. This has led to the suggestion that there was once an additional population of dwarf galaxies which has since disappeared, ie. there is non-conservation of galaxy number. Here we investigate the possibility that these disappearing dwarfs have actually evolved to become the population of very low surface brightness galaxies which is now being detected in nearby clusters.
Comparison of cosmological models using standard rulers and candles

In this paper, we used standard rulers and standard candles (separately and jointly) to explore five popular dark energy models under the assumption of the spatial flatness of the Universe. As standard rulers, we used a data set comprised of 118 galactic scale strong lensing systems (individual standard rulers if properly calibrated for the mass density profile) combined with BAO diagnostics (statistical standard ruler). Type Ia supernovae served as standard candles. Unlike most previous statistical studies involving strong lensing systems, we relaxed the assumption of a singular isothermal sphere (SIS) in favor of its generalization: the power-law mass density profile. Therefore, along with cosmological model parameters, we fitted the power law index and its first derivative with respect to the redshift (thus allowing for mass density profile evolution). It turned out that the best fitted γ parameters are in agreement with each other, irrespective of the cosmological model considered. This demonstrates that galactic strong lensing systems may provide a complementary probe to test the properties of dark energy. The fits for cosmological model parameters which we obtained are in agreement with alternative studies performed by other researchers. Because standard rulers and standard candles have different parameter degeneracies, a combination of standard rulers and standard candles gives much more restrictive results for cosmological parameters. Finally, we attempted an analysis based on model selection using information theoretic criteria (AIC and BIC). Our results support the claim that the cosmological constant model is still best and there is no (at least statistical) reason to prefer any other more complex model.
Long-Term Effectiveness of Hepatitis B Vaccination in the Protection of Healthcare Students in Highly Developed Countries: A Systematic Review and Meta-Analysis

Hepatitis B virus represents an important global health problem. In highly developed countries, mass vaccination campaigns of newborns in recent decades have drastically reduced the proportion of carriers. However, workers exposed to blood and body fluids, including healthcare students, can be at risk of exposure. In order to assess the proportion of susceptible individuals in the specific population of healthcare students in highly developed countries, a systematic review and meta-analysis was performed to summarize the evidence on the persistence of humoral immune protection induced by the primary cycle of hepatitis B vaccination, as well as the proportion of true non-responders. Forty-six studies were included in the final analysis (52,749 participants). Overall, the seroprotection prevalence at the pre-exposure assessment was equal to 73.8% (95% CI 69.1–78.0); the prevalence of anamnestic response following the administration of a challenge dose was 90.9% (95% CI 87.7–93.3), demonstrating a high proportion of persistence of vaccination-induced immunity. Among those without evidence of anamnestic response, 5.0% (95% CI 2.1–11.5) were non-responders following the completion of a secondary immunization cycle. These findings demonstrate that the majority of healthcare students vaccinated with the complete HBV primary cycle maintain an effective humoral immunity against this pathogen for over two decades.