Miracle-dz/UniFAR-FTUs huggingface dataset:
Where do long‐period comets come from? 26 comets from the non‐gravitational Oort spike

Since 1950, when Oort published his hypothesis, several important new facts have been established in this field. At present, there are still questions surrounding the apparent source region (or regions) of long-period comets, the definition of dynamically new comets and the characteristics of the hypothetical Oort Cloud. Our aim in this investigation is to look for the apparent source of selected long-period comets and to refine the definition of dynamically new comets. Based on pure gravitational original orbits, all comets studied in this paper are widely called dynamically new. However, we show that the incorporation of non-gravitational forces into the orbit determination process significantly changes the situation. We have determined the precise non-gravitational orbits of all investigated comets. Then, we have followed numerically their past and future motions during one orbital period. Applying the ingenious method of Sitarski of creating swarms of virtual comets compatible with observations, we have been able to derive the uncertainties of original and future orbital elements, as well as the uncertainties of previous and next perihelion distances. We conclude that the past and future evolutions of cometary orbits under Galactic tide perturbations is the only way to find which comets are really dynamically new. In our sample, fewer than 30 per cent of comets are, in fact, dynamically new. Most of these have small previous perihelion distances. However, 60 per cent of these will be lost on hyperbolic orbits in the future. This evidence suggests that the investigation into the apparent source of long-period comets is challenging. We have also shown that a significant percentage of long-period comets can visit the zone of visibility during at least two or three consecutive perihelion passages.
Short-Circuit Performance Investigation of 10kV+ Rated SiC n-IGBT

This paper presents a comprehensive short-circuit robustness investigation of 4H- Silicon Carbide (SiC) n-type Insulated Gate Bipolar Transistors (nIGBTs) for Medium-Voltage and High- Voltage applications. Numerical electrothermal TCAD simulations evaluate the IGBT short-circuit behaviour under various conditions and device parameters variation. The internal device current density and temperature distribution show that the parasitic thyristor latch-up and the thermally-assisted leakage current generation can be the failure mechanism of SiC nIGBT when the device temperature in the p-well/n-emitter interface region is about 1500K.
Black holes with bottle-shaped horizons

We present a new class of four-dimensional AdS black holes with non-compact event horizons of finite area. The event horizons are topologically spheres with one puncture, with the puncture pushed to infinity in the form of a cusp. Because of the shape of their event horizons, we call such black holes "black bottles". The solution was obtained as a special case of the Plebanski-Demianski solution, and may describe either static or rotating black bottles. For certain ranges of parameters, an acceleration horizon may also appear in the space-time. We study the full parameter space of the solution, and the various limiting cases that arise. In particular, we show how the rotating black hole recently discovered by Klemm arises as a special limit.
Extremal Surfaces in Asymptotically AdS Charged Boson Stars Backgrounds

In this paper, inspired by the holographic dual of the entanglement entropy, we consider the behaviour of extremal, codimension two, spacelike surfaces in the background of three and four dimensional charged boson stars in asymptotically anti-de Sitter spacetime. We find conditions for which families of minimal area surfaces fail to contain the entire bulk spacetime and construct a phase diagram showcasing the transition between regimes. In addition, we use the relation between the star's mass and the central density of the scalar field to argue for a possible instability of such hollow solutions. Finally, we discuss the consequences of our findings for the study of holographic duals of reduced density matrices.
Solitary waves in parity-time (PT)–symmetric Bragg grating structure and the existence of optical rogue waves

In this work, we have studied the traveling wave solution in a nonlinear Bragg grating structure in which the core of the optical fiber is having parity-time (PT)–symmetric refractive index distribution. Below the PT-threshold, we have found a bright-solitary-wave solution for forward waves and a dark-solitary-wave solution for backward waves. The effects of increasing the traveling wave speed on the spatio-temporal evolutions of the analytical solutions have been shown and above the PT-threshold, emergence of the optical rogue waves (ORWs) has been explored based on the system parameters.
TIDAL TAILS OF MINOR MERGERS. II. COMPARING STAR FORMATION IN THE TIDAL TAILS OF NGC 2782

The peculiar spiral NGC 2782 is the result of a minor merger with a mass ratio ∼4: 1 occurring ∼200 Myr ago. This merger produced a molecular and H i-rich, optically bright eastern tail and an H i-rich, optically faint western tail. Non-detection of CO in the western tail by Braine et al. suggested that star formation had not yet begun. However, deep UBVR and Hα narrowband images show evidence of recent star formation in the western tail, though it lacks massive star clusters and cluster complexes. Using Herschel PACS spectroscopy, we discover 158 μm [C ii] emission at the location of the three most luminous Hα sources in the eastern tail, but not at the location of the even brighter Hα source in the western tail. The western tail is found to have a normal star formation efficiency (SFE), but the eastern tail has a low SFE. The lack of CO and [C ii] emission suggests that the western tail H ii region may have a low carbon abundance and be undergoing its first star formation. The western tail is more efficient at forming stars, but lacks massive clusters. We propose that the low SFE in the eastern tail may be due to its formation as a splash region where gas heating is important even though it has sufficient molecular and neutral gas to make massive star clusters. The western tail, which has lower gas surface density and does not form high-mass star clusters, is a tidally formed region where gravitational compression likely enhances star formation.
A MULTIWAVELENGTH STUDY OF A SAMPLE OF 70 μm SELECTED GALAXIES IN THE COSMOS FIELD. II. THE ROLE OF MERGERS IN GALAXY EVOLUTION

We analyze the morphological properties of a large sample of 1503 70 μm selected galaxies in the COSMOS field spanning the redshift range 0.01 < z < 3.5 with a median redshift of 0.5 and an infrared luminosity range of 108 < LIR(8 − 1000 μm)< 1014L☉ with a median luminosity of 1011.4 L☉. In general, these galaxies are massive, with a stellar mass range of 1010–1012 M☉, and luminous, with −25 < MK < −20. We find a strong correlation between the fraction of major mergers and LIR, with the fraction at the highest luminosity (LIR > 1012 L☉) being up to ∼50%. We also find that the fraction of spirals drops dramatically with LIR. Minor mergers likely play a role in boosting the infrared luminosity for sources with low luminosities (LIR < 1011.5 L☉). The precise fraction of mergers in any given LIR bin varies by redshift due to sources at z > 1 being difficult to classify and subject to the effects of bandpass shifting; therefore, these numbers can only be considered lower limits. At z < 1, where the morphological classifications are most robust, major mergers clearly dominate the ULIRG population (∼50%–80%) and are important for the LIRG population (∼25%–40%). At z > 1, the fraction of major mergers is lower, but is at least 30%–40% for ULIRGs. In a comparison of our visual classifications with several automated classification techniques we find general agreement; however, the fraction of identified mergers is underestimated due to automated classification methods being sensitive to only certain timescales of a major merger. Although the general morphological trends agree with what has been observed for local (U)LIRGs, the fraction of major mergers is slightly lower than seen locally. This is in part due to the difficulty of identifying merger signatures at high redshift. The distribution of the U − V color of the galaxies in our sample peaks in the green valley (〈U − V〉 = 1.1) with a large spread at bluer and redder colors and with the major mergers peaking more strongly in the green valley than the rest of the morphological classes. We argue that, given the number of major gas-rich mergers observed and the relatively short timescale that they would be observable in the (U)LIRG phase, it is plausible for the observed red sequence of massive ellipticals (<1012 M☉) to have been formed entirely by gas-rich major mergers.
VALES - III. The calibration between the dust continuum and interstellar gas content of star-forming galaxies

We present the calibration between the dust continuum luminosity and interstellar gas content obtained from the Valparaiso ALMA Line Emission Survey (VALES) sample of 67 main-sequence star-forming galaxies at 0.02 < z < 0.35. We use CO(1–0) observations from the Atacama Large Millimetre/submillimetre Array to trace the molecular gas mass, MH2, and estimate the rest-frame monochromatic luminosity at 850 µm, Lν850, by extrapolating the dust continuum from MAGPHYS modelling of the far-ultraviolet to submillimetre spectral energy distribution sampled by the Galaxy And Mass Assembly survey. Adopting αCO = 6.5 (K km s−1 pc2)−1, the average ratio of Lν850 /MH2 = (6.4 ± 1.4)× 1019 erg s−1 Hz−1 M−1Θ, in excellent agreement with literature values. We obtain a linear fit of log10 (MH2/MΘ) = (0.92 ± 0.02) log10(Lν850 /erg s−1 Hz−1) − (17.31 ± 0.59). We provide relations between Lν850, MH2 and MISM when combining the VALES and literature samples, and adopting a Galactic αCO value.
The Turbulent Boundary Layer on a Horizontally Moving, Partially Submerged, Surface-Piercing Vertical Wall

The complex interactions between turbulence and the free surface, including air entrainment processes, in boundary layer shear flows created by vertical surface-piercing plates are considered. A laboratory-scale device was built that utilizes a surface-piercing stainless steel belt that travels in a loop around two vertical rollers, with one length of the belt between the rollers acting as a horizontally-moving flat wall. The belt is operated both as a suddenly-started plate to reproduce boundary layer flow or at steady state in the presence of a stationary flat plate positioned parallel to the belt to create a Couette flow with a free surface. Surface profiles are measured with a cinematic laser-induced fluorescence system in both experiments and air entrainment events and bubble motions are observed with stereo underwater white-light movies in the suddenly started belt experiment. It is found that the RMS surface height fluctuations, $\eta$, peak near the boundaries of the flows and increase approximately linearly with belt speed. In the Couette flow experiments, a dominant peak in the spectrum of $\partial\eta/\partial t$ is found at the dimensionless frequency $fH/U\approx 0.7$. In the suddenly started belt experiment, surface fluctuations appear to be strongly influenced by sub-surface turbulence within the boundary layer, while ripples propagate freely when farther from the belt. Additionally, some mechanisms for air entrainment are observed and comparisons are made to predictions of incipient entrainment conditions in Brocchini and Pregrine (J. Fluid Mech., 499, 225-254, 2001).
Correlations of neutron multiplicity and γ -ray multiplicity with fragment mass and total kinetic energy in spontaneous fission of Cf 252

Author(s): Wang, T; Li, G; Zhu, L; Meng, Q; Wang, L; Han, H; Zhang, W; Xia, H; Hou, L; Vogt, R; Randrup, J | Abstract: © 2016 American Physical Society. The dependence of correlations of neutron multiplicity ν and γ-ray multiplicity Mγ in spontaneous fission of Cf252 on fragment mass A∗ and total kinetic energy (TKE) have been investigated by employing the ratio of Mγ/ν and the form of Mγ(ν). We show for the first time that Mγ and ν have a complex correlation for heavy fragment masses, while there is a positive dependence of Mγ for light fragment masses and for near-symmetric mass splits. The ratio Mγ/ν exhibits strong shell effects for neutron magic number N=50 and near doubly magic number shell closure at Z=50 and N=82. The γ-ray multiplicity Mγ has a maximum for TKE=165-170 MeV. Above 170 MeV Mγ(TKE) is approximately linear, while it deviates significantly from a linear dependence at lower TKE. The correlation between the average neutron and γ-ray multiplicities can be partly reproduced by model calculations.
The M-dwarfs in Multiples (MinMs) survey – I. Stellar multiplicity among low-mass stars within 15 pc

We present a large-scale, volume-limited companion survey of 245 late-K to mid-M (K7-M6) dwarfs within 15 pc. Infrared adaptive optics (AO) data were analysed from the Very Large Telescope, Subaru Telescope, Canada-France-Hawaii Telescope, and MMT Observatory to detect close companions to the sample from $\sim$1 au to 100 au, while digitised wide-field archival plates were searched for wide companions from $\sim$100 au to 10,000 au. With sensitivity to the bottom of the main sequence over a separation range of 3 au to 10,000 au, multiple AO and wide-field epochs allow us to confirm candidates with common proper motions, minimize background contamination, and enable a measurement of comprehensive binary statistics. We detected 65 co-moving stellar companions and find a companion star fraction of $23.5 \pm 3.2$ per cent over the 3 au to 10,000 au separation range. The companion separation distribution is observed to rise to a higher frequency at smaller separations, peaking at closer separations than measured for more massive primaries. The mass ratio distribution across the $q = 0.2 - 1.0$ range is flat, similar to that of multiple systems with solar-type primaries. The characterisation of binary and multiple star frequency for low-mass field stars can provide crucial comparisons with star forming environments and hold implications for the frequency and evolutionary histories of their associated disks and planets.
X-RAY POLARIZATION FROM ACCRETING BLACK HOLES: CORONAL EMISSION

We present new calculations of X-ray polarization from accreting black holes (BHs), using a Monte Carlo ray-tracing code in full general relativity. In our model, an optically thick disk in the BH equatorial plane produces thermal seed photons with polarization oriented parallel to the disk surface. These seed photons are then inverse-Compton scattered through a hot (but thermal) corona, producing a hard X-ray power-law spectrum. We consider three different models for the corona geometry: a wedge “sandwich” with aspect ratio H/R and vertically integrated optical depth τ0 constant throughout the disk; an inhomogeneous “clumpy” corona with a finite number of hot clouds distributed randomly above the disk within a wedge geometry; and a spherical corona of uniform density, centered on the BH and surrounded by a truncated thermal disk with inner radius Redge. In all cases, we find a characteristic transition from horizontal polarization at low energies to vertical polarization above the thermal peak; the vertical direction is defined as the projection of the BH spin axis on the plane of the sky. We show how the details of the spectropolarization signal can be used to distinguish between these models and infer various properties of the corona and BH. Although the bulk of this paper focuses on stellar-mass BHs, we also consider the effects of coronal scattering on the X-ray polarization signal from supermassive BHs in active galactic nuclei.
Zoology of fractional Chern insulators

We study four different models of Chern insulators in the presence of strong electronic repulsion at partial fillings. We observe that all cases exhibit a Laughlin-like phase at filling fraction $1/3$. We provide evidence of such a strongly correlated topological phase by studying both the energy and the entanglement spectra. In order to identify the key ingredients of the emergence of Laughlin physics in these systems, we show how they are affected when tuning the band structure. We also address the question of the relevance of the Berry curvature flatness in this problem. Using three-body interactions, we show that some models can also host a topological phase reminiscent of the $\ensuremath{\nu}=1/2$ Pfaffian Moore-Read state. Additionally, we identify the structures indicating cluster correlations in the entanglement spectra.
ATMOSPHERIC CIRCULATION AND COMPOSITION OF GJ1214b

The exoplanet GJ1214b presents an interesting example of compositional degeneracy for low-mass planets. Its atmosphere may be composed of water, super-solar or solar metallicity material. We present atmospheric circulation models of GJ1214b for these three compositions, with explicit gray radiative transfer and an optional treatment of MHD bottom drag. All models develop strong, superrotating zonal winds (∼1–2 km s−1). The degree of eastward heat advection, which can be inferred from secondary eclipse and thermal phase curve measurements, varies greatly between the models. These differences are understood as resulting from variations in the radiative times at the thermal photosphere, caused by separate molecular weight and opacity effects. Our GJ1214b models illustrate how atmospheric circulation can be used as a probe of composition for similar tidally locked exoplanets in the mini-Neptune/waterworld class.
Centrality dependence of charged-hadron pseudorapidity distributions in PbPb collisions at LHC energies in the RDM

The centrality dependence of charged-hadron production in relativistic heavy-ion collisions at LHC energies is investigated in a nonequilibrium-statistical relativistic diffusion model (RDM) with three sources. Theoretical pseudorapidity distributions are compared with preliminary PbPb ALICE data at LHC energy of sqrt(s_NN) = 2.76 TeV for seven centralities, and a previous RDM prediction for this energy is confronted with the data. Refined predictions for 5.52 TeV PbPb based on RDM parameter extrapolations are presented.
On Utilizing Unused Slots In Topology-Transparent TDMA MAC Policies for Ad Hoc Networks

In the age of the Internet of Things, numerous devices of diverse characteristics are communicating with each other. The underlying networks supporting those communications can either use some sort of infrastructure or implement an ad hoc network. For the latter type of networks and depending on the application requirements, Topology-Transparent TDMA MAC policies can be considered as they are inherently suited for dynamic and unstructured topologies. However, such TDMA-based schemes may suffer from low throughput performance, especially in sparse networks, where a significant portion of available time slots remains unused. To address this challenge, a Topology-Transparent TDMA MAC policy is revisited in this paper, which utilizes unused slots by allowing nodes to transmit in them under a common and fixed probability $p$. Additionally, an improvement is proposed, where every node can calculate its own individual access probability based on information gathered from its local neighborhood. Simulation results demonstrate that the use of the individual access probability leads to improved performance in terms of system throughput. Moreover, the requirement for assigning a value to probability $p$ during the network initialization is relaxed, as this value is now calculated dynamically and distributively during the network operation.
Abundances of 59Co and 59Ni in the cosmic ray flux

Two main hypotheses for the origin of Galactic cosmic rays are the "supernova" and "superbubble" origin hypotheses. We analyse the evidence for the superbubble hypothesis provided by the measurements of the relativive abundances of isotopes of cobalt and nickel in the cosmic ray flux. We compare the measured upper limit on the abundance of 59Ni in the cosmic ray flux with the 59Ni abundance predictions of the up-to-date stellar evolution models. Non-detection of 59Ni in the cosmic ray flux has previously been attributed to a large time delay of the order of 1e5 yr between the moment of supernova explosion and the onset of particle acceleration process. This large time delay was considered as an argument in favour of the "superbubble" scenario. We show that the recent calculation of the 59Ni yield of massive stars, which takes into account the initial mass range up to 120 solar masses and includes stellar rotation, results in prediction of low 59Ni abundance relative to its decay product 59Co. The predicted abundance is consistent with the upper bound on 59Ni abundance in the cosmic ray flux for the supernova parameters assumed. This result removes the necessity of decay of 59Ni in the time interval between the supernova explosion and the onset of acceleration process and restores the consistency of measurements of 59Ni / 59Co abundances with the "supernova" hypothesis of the CR origin.
Probing lepton asymmetry with 21 cm fluctuations

We investigate the issue of how accurately we can constrain the lepton number asymmetry ξν=μν/Tν in the Universe by using future observations of 21 cm line fluctuations and cosmic microwave background (CMB). We find that combinations of the 21 cm line and the CMB observations can constrain the lepton asymmetry better than big-bang nucleosynthesis (BBN). Additionally, we also discuss constraints on ξν in the presence of some extra radiation, and show that the 21 cm line observations can substantially improve the constraints obtained by CMB alone, and allow us to distinguish the effects of the lepton asymmetry from the ones of extra radiation.
Initial data release from the INT Photometric Hα Survey of the Northern Galactic Plane (IPHAS)

The INT/WFC Photometric Hα Survey of the Northern Galactic Plane (IPHAS) is an imaging survey being carried out in Hα, rand ifilters, with the Wide Field Camera (WFC) on the 2.5-metre Isaac Newton Telescope (INT) to a depth of r ' =20 (10σ). The survey is aimed at revealing the large scale organisation of the Milky Way and can be applied to identifying a range of stellar populations within it. Mapping emission line objects enables a particular focus on objects in the young and old stages of stellar evolution ranging from early T-Tauri stars to late planetary nebulae. In this paper we present the IPHAS Initial Data Release, primarily a photometric catalogue of about 200 million unique objects, coupled with associated image data covering about 1,600 square degrees in three passbands. We note how access to the primary data products has been implemented through use of standard virtual observatory publishing interfaces. Simple traditional web access is provided to the main IPHAS photometric catalogue, in addition to a number of common catalogues (such as 2MASS) which are of immediate relevance. Access through the AstroGrid VO Desktop opens up the full range of analysis options, and allows full integration with the wider range of data and services available through the Virtual Observatory. The IDR represents the largest dataset published primarily through VO interfaces to date, and so stands as
Salt Polygons and Porous Media Convection

From fairy circles to patterned ground and columnar joints, natural patterns spontaneously appear in many complex geophysical settings. Here, we investigate the origins of polygonally patterned crusts of salt playa and salt pans. These beautifully regular features, approximately a meter in diameter, are found worldwide and are fundamentally important to the transport of salt and dust in arid regions. We show that they are consistent with the surface expression of buoyancy-driven convection in the porous soil beneath a salt crust. By combining quantitative results from direct field observations, analogue experiments and numerical simulations, we further determine the conditions under which salt polygons should form, as well as how their characteristic size emerges.