Miracle-dz/UniFAR-FTUs huggingface dataset:
CCD time-series photometry of the globular cluster NGC 5053: RR Lyrae, Blue Stragglers and SX Phoenicis stars revisited

We report the results of CCD V, r and I time-series photometry of the globular cluster NGC 5053. New times of maximum light are given for the eight known RR Lyrae stars in the field of our images, and their periods are revised. Their V light curves were Fourier decomposed to estimate their physical parameters. A discussion on the accuracy of the Fourier-based iron abundances, temperatures, masses and radii is given. New periods are found for the five known SX Phe stars, and a critical discussion of their secular period changes is offered. The mean iron abundance for the RR Lyrae stars is found to be [Fe/H] ~ - 1.97 ± 0.16 and lower values are not supported by the present analysis. The absolute magnitude calibrations of the RR Lyrae stars yield an average true distance modulus of 16.12 ± 0.04 or a distance of 16.7 ± 0.3 kpc. Comparison of the observational colour magnitude diagram (CMD) with theoretical isochrones indicates an age of 12.5 ± 2.0 Gyr for the cluster. A careful identification of all reported blue stragglers (BS) and their V, I magnitudes leads to the conclusion that BS12, BS22, BS23 and BS24 are not BS. On the other hand, three new BS are reported. Variability was found in seven BS, very likely of the SX Phe type in five of them, and in one red giant star. The new SX Phe stars follow established Period-Luminosity relationships and indicate a distance in agreement with the distance from the RR Lyrae stars.
Present status on experimental search for pentaquarks

It has been ten years since the first report for a positive strangeness pentaquark-like baryon state. However, the existence of the pentaquark state is still controversial. Some contradictions between the experiments are unsolved. In this paper, we review the experimental search for the pentaquark candidates Θ+, Θ++, Ξ- -, and N* in detail. We review the experiments with positive results and compare the experiments with similar conditions but opposite results.
Effect of Wetting and Drying Cycles on the Dynamic Properties of Compacted Loess

This paper investigates the dynamic properties of compacted loess under wetting and drying (W-D) cycles. A series of tests were conducted on compacted loess samples, namely, the soil dynamic triaxial test and the scanning electron microscopy (SEM) test. The test results showed that the dynamic stress-strain relationship of the compacted loess under the action of W-D cycles accords with the Hardin–Drnevich model. The initial dynamic shear modulus (G0) and the maximum dynamic shear stress (τy) of the compacted loess first decreased and then increased with the number of W-D cycles (n) increasing. The damping ratio (λ) increased linearly with the dynamic strain (εd) increasing in the semilogarithmic coordinate. The defined change rate of the damping ratio (η) first increased and then decreased with the n increasing. The macrostructure and microstructure characteristics of samples in the process of W-D cycles indicate that the increasing number of pores in the humidifying process and the cracks on the surface and inside of samples during dehumidification lead to the structural damage and dynamic properties reduction of compacted loess. The main reasons for structure strengthening and dynamic properties increasing are that soil particle structure develops to mosaic structure, pore structure develops to uniform small pore, and matrix suction makes soil sample tend to be dense.
La-doped BiFeO 3 junction based random access multilevel nonvolatile memory Microelectronic Engineering

Resistive switching devices are promising candidates for the next generation nonvolatile memories due to their outstanding performance, simplicity, and scalability. Among them, developing multilevel resistive switching has attracted great attention for its potential in significantly improving information storage density but without extra energy consumption. Although continuous multilevel resistive switching (CMRS) has been observed in many metal oxides and organic materials, achieving random access multilevel nonvolatile memories (RAMNM) with high speed and reliability is still pressingly needed for practical applications. Here, we have successfully fabricated a RAMNM based on high – performance pulse-width modulated memristive ferroelectric tunnel junctions (FTJs) of Pt/La 0.1 Bi 0.9 FeO 3 /Nb:SrTiO 3 with giant switching ratios above 4 × 10 5 at room temperature.
Spectrum of gravitational radiation from primordial turbulence

Energy injection into the early universe can induce turbulent motions of the primordial plasma, which in turn act as a source for gravitational radiation. Earlier work computed the amplitude and characteristic frequency of the relic gravitational wave background, as a function of the total energy injected and the stirring scale of the turbulence. This paper computes the frequency spectrum of relic gravitational radiation from a turbulent source of the stationary Kolmogoroff form which acts for a given duration, making no other approximations. We also show that the limit of long source wavelengths, commonly employed in aeroacoustic problems, is an excellent approximation. The gravitational waves from cosmological turbulence around the electroweak energy scale will be detectable by future space-based laser interferometers for a substantial range of turbulence parameters.
The Impact of Nuclear Star Formation on Gas Inflow to AGN

Abstract Our adaptive optics observations of nearby AGN at spatial resolutions as small as 0. ″085 show strong evidence for recent, but no longer active, nuclear star formation. We begin by describing observations that highlight two contrasting methods by which gas can flow into the central tens of parsecs. Gas accumulation in this region will inevitably lead to a starburst, and we discuss the evidence for such events. We then turn to the impact of stellar evolution on the further inflow of gas by combining a phenomenological approach with analytical modelling and hydrodynamic simulations. These complementary perspectives paint a picture in which all the processes are ultimately regulated by the mass accretion rate into the central hundred parsecs, and the ensuing starburst that occurs there. The resulting supernovae delay accretion by generating a starburst wind, which leaves behind a clumpy interstellar medium. This provides an ideal environment for slower stellar outflows to accrete inwards and form a dense turbulent disk on scales of a few parsecs. Such a scenario may resolve the discrepancy between the larger scale structure seen with adaptive optics and the small-scale structure seen with VLTI.
$V_{cs}$ from $D_s \to \phi \ell \nu$ semileptonic decay and full lattice QCD

We determine the complete set of axial and vector form factors for the Ds→ϕlν decay from full lattice QCD for the first time. The valence quarks are implemented using the highly improved staggered quark action and we normalize the appropriate axial and vector currents fully nonperturbatively. The q2 and angular distributions we obtain for the differential rate agree well with those from the BABAR experiment and, from the total branching fraction, we obtain Vcs=1.017(63), in good agreement with that from D→Klν semileptonic decay. We also find the mass and decay constant of the ϕ meson in good agreement with experiment, showing that its decay to KK¯ (which we do not include here) has at most a small effect. We include an Appendix on nonperturbative renormalization of the complete set of staggered vector and axial vector bilinears needed for this calculation.
Hemispherical Asymmetry and Local non-Gaussianity: a Consistency Condition

In this paper we provide a consistency relation between the amplitude of the hemispherical bipolar asymmetry, $A$, and the amplitude of the primordial non-Gaussianity in the squeezed limit, ${f}_{NL}$, as $|A|\ensuremath{\lesssim}{10}^{\ensuremath{-}1}{f}_{NL}$. We demonstrate that this consistency condition is at work for any model of inflation in which the curvature perturbations are sourced by a single light field with the Bunch\char21{}Davies initial condition, irrespective of the number of inflation fields that contribute to the background inflationary expansion. As a nontrivial example, we show that observable hemispherical asymmetry can be generated in single-field nonattractor inflationary models. We also study hemispherical asymmetry generated in the models of multiple fields inflation. We show that $A$ is controlled by the weighted sum of non-Gaussianity contribution from each field. In particular, we show that observable hemispherical asymmetry can be generated in models in which inhomogeneities are generated from a light scalar field modulating the surface of the end of inflation.
The kinematic properties of BHB and RR Lyrae stars towards the Anticentre and the North Galactic Pole: the transition between the inner and the outer halo

We identify 51 blue horizontal branch (BHB) stars, 12 possible BHB stars and 58 RR Lyrae stars in Anticentre fields. Their selection does not depend on their kinematics. Light curves and ephemerides are given for seven previously unknown RR Lyrae stars. All but four of the RR Lyrae stars are of Oosterhoff type I. Our selection criteria for BHB stars give results that agree with those used by Smith et al. and Ruhland et al. We use five methods to determine distances for the BHB stars and three methods for the RR Lyrae stars to get distances on a uniform scale. Absolute proper motions [largely derived from the Second Guide Star Catalogue (GSCII) and Sloan Digital Sky Survey (Seventh Data Release) data bases] are given for these stars; radial velocities are given for 31 of the BHB stars and 37 of the RR Lyrae stars. Combining these data for BHB and RR Lyrae stars with those previously found in fields at the North Galactic Pole, we find that retrograde orbits dominate for galactocentric distances greater than 12.5 kpc. The majority of metal-poor stars in the solar neighbourhood are known to be concentrated in a L⊥ versus Lz angular momentum plot. We show that the ratio of the number of outliers to the number in the main concentration increases with galactocentric distance. The location of these outliers with L⊥ and Lz shows that the halo BHB and RR Lyrae stars have more retrograde orbits and a more spherical distribution with increasing galactocentric distance. Six RR Lyrae stars are identified in the H99 group of outliers; the small spread in their [Fe/H] suggests that they could have come from a single globular cluster. Another group of outliers contains two pairs of RR Lyrae stars; the stars in each pair have similar properties.
THE OBSCURED FRACTION OF ACTIVE GALACTIC NUCLEI IN THE XMM-COSMOS SURVEY: A SPECTRAL ENERGY DISTRIBUTION PERSPECTIVE

The fraction of active galactic nucleus (AGN) luminosity obscured by dust and re-emitted in the mid-IR is critical for understanding AGN evolution, unification, and parsec-scale AGN physics. For unobscured (Type 1) AGNs, where we have a direct view of the accretion disk, the dust covering factor can be measured by computing the ratio of re-processed mid-IR emission to intrinsic nuclear bolometric luminosity. We use this technique to estimate the obscured AGN fraction as a function of luminosity and redshift for 513 Type 1 AGNs from the XMM-COSMOS survey. The re-processed and intrinsic luminosities are computed by fitting the 18 band COSMOS photometry with a custom spectral energy distribution fitting code, which jointly models emission from hot dust in the AGN torus, from the accretion disk, and from the host galaxy. We find a relatively shallow decrease of the luminosity ratio as a function of Lbol, which we interpret as a corresponding decrease in the obscured fraction. In the context of the receding torus model, where dust sublimation reduces the covering factor of more luminous AGNs, our measurements require a torus height that increases with luminosity as . Our obscured-fraction–luminosity relation agrees with determinations from Sloan Digital Sky Survey censuses of Type 1 and Type 2 quasars and favors a torus optically thin to mid-IR radiation. We find a much weaker dependence of the obscured fraction on 2–10 keV luminosity than previous determinations from X-ray surveys and argue that X-ray surveys miss a significant population of highly obscured Compton-thick AGNs. Our analysis shows no clear evidence for evolution of the obscured fraction with redshift.
Quantum statistics and the momentum distribution of liquid parahydrogen

Extensive Monte Carlo simulations of bulk liquid para-hydrogen at a temperature T=16.5 K have been carried out using the continuous-space Worm Algorithm. Results for the momentum distribution, as well as for the kinetic energy per particle and the pair correlation function are reported. The static equilibrium thermodynamic properties of this system can be generally computed by assuming that molecules are distinguishable. However, the one-body density matrix (and the associated momentum distribution) are affected by particle indistinguishability and quantum statistics, to an extent that lends itself to experimental observation. Comparisons with available experimental data and other theoretical and numerical calculations are offered.
KCH representations, augmentations, and $A$-polynomials

We describe a correspondence between augmentations and certain representations of the knot group. The correspondence makes the 2-variable augmentation polynomial into a generalization of the classical $A$-polynomial. It also associates to an augmentation a rank, which is bounded by the bridge number and shares its behavior under connect sums. We also study augmentations with rank equal to the braid index.
Correlations of the divisor function

Let τ(n)= ∑d 1d|n denote the divisor function. Employing the methods Green and Tao developed in their work on prime numbers, we give an asymptotic for the following correlation En∈[ −N,N ]d∩K∏i=1tτ(ψi(n)), where Ψ=(ψ1,…, ψt) is a non‐degenerated system of affine‐linear forms no two of which are affinely related, and where K is a convex body. These correlations include, for example, the following averages along k‐term arithmetic progressions for fixed integers k⩾ 2 E(τ(n)τ(n+d)…τ(n+(k−1)d)|n,d∈N,n+(k−1)d⩽ N). In the course of the proof, we construct a pointwise majorant function for a slightly smoothed version of τ that behaves quasi‐random in certain precise sense. This construction is based on Erdős's fundamental work on sums of multiplicative functions.
Does Considering Quantum Correlations Resolve the Information Paradox

In this paper, we analyze whether quantum correlations between successive steps of evaporation can open any way to resolve the black hole information paradox. Recently a celebrated result in literature shows that `small' correction to leading order Hawking analysis fails to restore unitarity in black hole evaporation. We study a toy qubit model of evaporation allowing small quantum correlations between successive steps and verify the previous result. Then we generalize the concept of correction to Hawking state by relaxing the `smallness' condition. Our result generates a nontrivial upper and lower bound on change in entanglement entropy in the evaporation process. This gives us a quantitative measure of correction that would mathematically facilitate restoration of unitarity in black hole evaporation. We then investigate whether this result is compatible to the established physical constraints of unitary evolution of a state in a subsystem. We find that the generalized bound on entanglement entropy leads to significant deviation from Page curve. This leads us to agree with the recent claim in literature that no amount of correction in the form of Bell pair states would lead to any resolution to the information paradox.
Calculating the maximum possible yield for a typical pyroelectric neutron generator

Pyroelectric crystals are heated/cooled to supply D-D/D-T fusion for the purpose of neutron generation. Enhancing the pyroelectric neutron generators (PNG) yield is one of the main goals pursued by most of the previously developed techniques/models. Here, the maximum possible neutron yield of a PNG is calculated in which a widely-used pyroelectric crystal (i.e., LiTaO3 with a diameter of 3 cm and height of 1 cm) is applied. This calculation is performed by a simulation procedure including: (1) computation of the PNG potential/current for neutron generation based on new modifications (2) simulation of the deuterium ions acceleration into the target during a thermal cycle (3) simulation of the D-D fusion interaction using the Geant4 toolkit. The results show that the maximum yield of the PNG in the ideal conditions is about 6.4× 106 neutrons per cycle. This study provides a useful approach for determining the upper limit of the expected efficiency for typical PNGs and other compact neutron generators.
Presumed Detection of C5 Molecule in the Interstellar Medium

The paper suggests the presence of the carbon chain C5 molecule in translucent, interstellar H i clouds. This species, the only five atom interstellar molecule, observable in dark, translucent clouds, seems to be observable in reasonably dense clouds, causing also rather high reddening. The paper shows two likely discovered spectral features of C5, A1Πu−X1Σg+ bands near 4975 and 5109 Å. The attempt to discover the 3789 Å C4 feature gave the negative result.
Mermin and Svetlichny inequalities for non-projective measurement observables

The necessary and sufficient criteria for violating the Mermin and Svetlichny inequalities by arbitrary three-qubit states are presented. Several attempts have been made, earlier, to find such criteria, however, those extant criteria are neither tight for most of the instances, nor fully general. We generalize the existing criteria for Mermin and Svetlichny inequalities which are valid for the local projective measurement observables as well as for the arbitrary ones. We obtain the maximal achievable bounds of the Mermin and Svetlichny operators with unbiased measurement observables for arbitrary three-qubit states and with arbitrary observables for three-qubit states having maximally mixed marginals. We find that for certain ranges of measurement strengths, it is possible to violate Mermin and Svetlichny inequalities only by biased measurement observables. The necessary and sufficient criteria of violating any one of the six possible Mermin and Svetlichny inequalities are also derived.
Densities of 3-vertex graphs

Let d_i(G) be the density of the 3-vertex i-edge graph in a graph G, i.e., the probability that three random vertices induce a subgraph with i edges. Let S be the set of all quadruples (d_0,d_1,d_2,d_3) that are arbitrary close to 3-vertex graph densities in arbitrary large graphs. Huang, Linial, Naves, Peled and Sudakov have recently determined the projection of the set S to the (d_0,d_3) plane. We determine the projection of the set S to all the remaining planes.
Spectrum of heavy baryons in the quark model

Single- and double- heavy baryons are studied in the constituent quark model. The model Hamiltonian is chosen as a standard one with two exceptions : (1) The color-Coulomb term depend on quark masses, and (2) an antisymmetric $LS$ force is introduced. Model parameters are fixed by the strange baryon spectra, $\Lambda$ and $\Sigma$ baryons. The masses of the observed charmed and bottomed baryons are, then, fairly well reproduced. Our focus is on the low-lying negative-parity states, in which the heavy baryons show specific excitation modes reflecting the mass differences of heavy and light quarks. By changing quark masses from the SU(3) limit to the strange quark mass, further to the charm and bottom quark masses, we demonstrate that the spectra change from the SU(3) symmetry patterns to the heavy quark symmetry ones.
Room-temperature bandlike transport and Hall effect in a high-mobility ambipolar polymer

The advent of a new class of high-mobility semiconducting polymers opens up a window to address fundamental issues in electrical transport mechanism such as transport between localized states versus extended state conduction. Here, we investigate the origin of the ultralow degree of disorder $({E}_{a}\ensuremath{\sim}16\phantom{\rule{0.16em}{0ex}}\mathrm{meV})$ and the ``bandlike'' negative temperature ($T$) coefficient of the field effect electron mobility: ${\ensuremath{\mu}}_{\mathrm{FET}}^{e}(T)$ in a high performance $({\ensuremath{\mu}}_{\mathrm{FET}}^{e}g2.5\phantom{\rule{0.16em}{0ex}}\mathrm{c}{\mathrm{m}}^{2}\phantom{\rule{0.28em}{0ex}}{\mathrm{V}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1})$ diketopyrrolopyrrole based semiconducting polymer. Models based on the framework of mobility edge with exponential density of states are invoked to explain the trends in transport. The temperature window over which the system demonstrates delocalized transport was tuned by a systematic introduction of disorder at the transport interface. Additionally, the Hall mobility $({\ensuremath{\mu}}_{\mathrm{Hall}}^{e})$ extracted from Hall voltage measurements in these devices was found to be comparable to field effect mobility $({\ensuremath{\mu}}_{\mathrm{FET}}^{e})$ in the high $T$ bandlike regime. Comprehensive studies with different combinations of dielectrics and semiconductors demonstrate the effectiveness of rationale molecular design, which emphasizes uniform-energetic landscape and low reorganization energy.
Chaotic dispersal of tidal debris

Several long, dynamically cold stellar streams have been observed around the Milky Way Galaxy, presumably formed from the tidal disruption of globular clusters. In integrable potentials---where all orbits are regular---tidal debris phase-mixes close to the orbit of the progenitor system. However, the Milky Way's dark matter halo is expected not to be fully integrable; an appreciable fraction of orbits will be chaotic. This paper examines the influence of chaos on the phase-space morphology of cold tidal streams. Streams even in weakly chaotic regions look very different from those in regular regions. We find that streams can be sensitive to chaos on a much shorter time-scale than any standard prediction (from the Lyapunov or frequency-diffusion times). For example, on a weakly chaotic orbit with a chaotic timescale predicted to be $>$1000 orbital periods ($>$1000 Gyr), the resulting stellar stream is, after just a few 10's of orbits, substantially more diffuse than any formed on a nearby but regular orbit. We find that the enhanced diffusion of the stream stars can be understood by looking at the variance in orbital frequencies of orbit ensembles centered around the parent (progenitor) orbit. Our results suggest that long, cold streams around our Galaxy must exist only on regular (or very nearly regular) orbits; they potentially provide a map of the regular regions of the Milky Way potential. This suggests a promising new direction for the use of tidal streams to constrain the distribution of dark matter around our Galaxy.
Production of cosmogenic isotopes 7Be, 10Be, 14C, 22Na, and 36Cl in the atmosphere: Altitudinal profiles of yield functions

New consistent and precise computations of the production of five cosmogenic radioisotopes, 7Be, 10Be, 14C, 22Na, and 36Cl, in the Earth's atmosphere by cosmic rays are presented in the form of tabulated yield functions. For the first time, a detailed set of the altitude profiles of the production functions is provided which makes it possible to apply the results directly as input for atmospheric transport models. Good agreement with most of the earlier published works for columnar and global isotopic production rates is shown. Altitude profiles of the production are important, in particular for such tasks as studies of strong solar particle events in the past, precise reconstructions of solar activity on long‐term scale, tracing air mass dynamics using cosmogenic radioisotopes, etc. As an example, computations of the 10Be deposition flux in the polar region are shown for the last decades and also for a period around 780 A.D. and confronted with the actual measurements in Greenland and Antarctic ice cores.