Miracle-dz/UniFAR-FTUs huggingface dataset:
Investigation of Galactic open cluster remnants: the case of NGC 7193

Galactic open clusters (OCs) that survive the early gas-expulsion phase are gradually destroyed over time by the action of disruptive dynamical processes. Their final evolutionary stages are characterized by a poorly populated concentration of stars called an open cluster remnant (OCR). This study is devoted to assessing the real physical nature of the OCR candidate NGC 7193. GMOS/Gemini spectroscopy of 53 stars in the inner target region were obtained to derive radial velocities and atmospheric parameters. We also employed photometric and proper motion data. The analysis method consists of the following steps: (i) analysis of the statistical resemblance between the cluster and a set of field samples with respect to the sequences defined in color-magnitude diagrams (CMDs); (ii) a 5-dimensional iterative exclusion routine was employed to identify outliers from kinematical and positional data; (iii) isochrone fitting to the Ks×(J−Ks) CMD of the remaining stars and the dispersion of spectral types along empirical sequences in the (J−H)×(H−Ks) diagram were checked. A group of stars was identified for which the mean heliocentric distance is compatible with that obtained via isochrone fitting and whose metallicities are compatible with each other. Fifteen of the member stars observed spectroscopically were identified together with another 19 probable members. Our results indicate that NGC 7193 is a genuine OCR, of a once very populous OC, for which the following parameters were derived: d = 501±46 pc, t=2.5±1.2Gyr, 〈[Fe/H]〉=−0.17±0.23 and E(B−V)=0.05±0.05. Its luminosity and mass functions show depletion of low mass stars, confirming the OCR is in a dynamically evolved state.
Quantum pseudorandomness from cluster-state quantum computation

We show how to efficiently generate pseudo-random states suitable for quantum information processing via cluster-state quantum computation. By reformulating pseudo-random algorithms in the cluster-state picture, we identify a strategy for optimizing pseudo-random circuits by properly choosing single-qubit rotations. A Markov chain analysis provides the tool for analyzing convergence rates to the Haar measure and finding the optimal single-qubit gate distribution. Our results may be viewed as an alternative construction of approximate unitary 2-designs.
Effective global generation on varieties with numerically trivial canonical class

We prove a Fujita-type theorem for varieties with numerically trivial canonical bundle. We deduce our result via a combination of algebraic and analytic methods, including the Kobayashi--Hitchin correspondence and positivity of direct image bundles. As an application, we combine our results with recent work of Riess on compact hyperkaehler manifolds and earlier work of Mukai and Yoshioka to obtain effective global generation statements for certain moduli spaces of sheaves on abelian surfaces.
Amplitudes of low-frequency modes in rotating B-type stars

Using the weakly non-linear theory of oscillation, we estimate the amplitudes of low-frequency modes in a slowly pulsating B star, taking account of the effects of rotation on the modes. Applying the formulation by Schenk et al., we compute the non-linear coupling coefficient between the low-frequency modes and estimate the equilibrium amplitudes of the modes excited in the star, assuming the amplitudes of the unstable modes are saturated as a result of non-linear coupling with stable modes, i.e. as a result of parametric instability expected between one unstable mode and two stable modes. We use the traditional approximation to calculate adiabatic and non-adiabatic oscillations in a rotating star. We find r-modes in a rapidly rotating star play a significant role in the amplitude determination through non-linear coupling. We also find that for low-m modes, the fractional amplitudes of the radiative luminosity caused by the low-frequency modes are of order 10−4 to 10−3 at the surface.
Search for photonic signatures of gauge-mediated supersymmetry in 8 TeV pp collisions with the ATLAS detector

A search is presented for photonic signatures motivated by generalized models of gauge-mediated supersymmetry breaking. This search makes use of 20 . 3 fb − 1 of proton-proton collision data at ﬃﬃﬃ s p ¼ 8 TeV recorded by the ATLAS detector at the LHC, and explores models dominated by both strong and electroweak production of supersymmetric partner states. Four experimental signatures incorporating an isolated photon and significant missing transverse momentum are explored. These signatures include events with an additional photon, lepton, b -quark jet, or jet activity not associated with any specific underlying quark flavor. No significant excess of events is observed above the Standard Model prediction and model-dependent 95% confidence-level exclusion limits are set.
Evolution of the dust coma in comet 67P/Churyumov-Gerasimenko before the 2009 perihelion

Comet 67P/Churyumov-Gerasimenko is the main target of ESA's Rosetta mission and will be encountered in May 2014. As the spacecraft shall be in orbit the comet nucleus before and after release of the lander {\it Philae}, it is necessary necessary to know the conditions in the coma. Study the dust environment, including the dust production rate and its variations along its preperihelion orbit. The comet was observed during its approach to the Sun on four epochs between early-June 2008 and mid-January 2009, over a large range of heliocentric distances that will be covered by the mission in 2014. An anomalous enhancement of the coma dust density was measured towards the comet nucleus. The scalelength of this enhancement increased with decreasing heliocentric distance of the comet. This is interpreted as a result of an unusually slow expansion of the dust coma. Assuming a spherical symmetric coma, the average amount of dust as well as its ejection velocity have been derived. The latter increases exponentially with decreasing heliocentric distance (\rh), ranging from about 1 m/s at 3 AU to about 25-35 m/s at 1.4 AU. Based on these results we describe the dust environment at those nucleocentric distances at which the spacecraft will presumably be in orbit. Astronomy and Astrophysics, in press
Early Science with the large millimeter telescope : observations of dust continuum and CO emission lines of cluster-lensed submillimetre galaxies at z=2.0-4.7

We present Early Science observations with the Large Millimeter Telescope, AzTEC 1.1 mm continuum images and wide bandwidth spectra (73–111 GHz) acquired with the Redshift Search Receiver, towards four bright lensed submillimetre galaxies identified through the Herschel Lensing Survey-snapshot and the Submillimetre Common-User Bolometer Array-2 Cluster Snapshot Survey. This pilot project studies the star formation history and the physical properties of the molecular gas and dust content of the highest redshift galaxies identified through the benefits of gravitational magnification. We robustly detect dust continuum emission for the full sample and CO emission lines for three of the targets. We find that one source shows spectroscopic multiplicity and is a blend of three galaxies at different redshifts (z = 2.040, 3.252, and 4.680), reminiscent of previous high-resolution imaging follow-up of unlensed submillimetre galaxies, but with a completely different search method, that confirm recent theoretical predictions of physically unassociated blended galaxies. Identifying the detected lines as 12CO (Jup = 2–5) we derive spectroscopic redshifts, molecular gas masses, and dust masses from the continuum emission. The mean H2 gas mass of the full sample is (2.0 ± 0.2) × 1011 M⊙/μ, and the mean dust mass is (2.0 ± 0.2) × 109 M⊙/μ, where μ ≈ 2–5 is the expected lens amplification. Using these independent estimations we infer a gas-to-dust ratio of δGDR ≈ 55–75, in agreement with other measurements of submillimetre galaxies. Our magnified high-luminosity galaxies fall on the same locus as other high-redshift submillimetre galaxies, extending the L′CO–LFIR correlation observed for local luminous and ultraluminous infrared galaxies to higher far-infrared and CO luminosities.
Global stability analysis of the axisymmetric wake past a spinning bullet-shaped body

Abstract We analyze the global linear stability of the axisymmetric flow around a spinning bullet-shaped body of length-to-diameter ratio $L/D=2$ , as a function of the Reynolds number, $Re=\rho w_{\infty } D /\mu $ , and of the rotation parameter $\varOmega =\omega D/(2 w_{\infty })$ , in the ranges $Re<450$ and $0\leq \varOmega \leq 1$ . Here, $w_{\infty }$ and $\omega $ are the free-stream and the body rotation velocities respectively, and $\rho $ and $\mu $ are the fluid density and viscosity. The two-dimensional eigenvalue problem (EVP) is solved numerically to find the spectrum of complex eigenvalues and their associated eigenfunctions, allowing us to explain the different bifurcations from the axisymmetric state observed in previous numerical studies. Our results reveal that, for the parameter ranges investigated herein, three global eigenmodes, denoted low-frequency (LF), medium-frequency (MF) and high-frequency (HF) modes, become unstable in different regions of the $(Re,\varOmega )$ -parameter plane. We provide precise computations of the corresponding neutral curves, that divide the $(Re,\varOmega )$ -plane into four different regions: the stable axisymmetric flow prevails for small enough values of $Re$ and $\varOmega $ , while three different frozen states, where the wake structures co-rotate with the body at different angular velocities, take place as a consequence of the destabilization of the LF, MF and HF modes. Several direct numerical simulations (DNS) of the nonlinear state associated with the MF mode, identified here for the first time, are also reported to complement the linear stability results. Finally, we point out the important fact that, since the axisymmetric base flow is $SO(2)$ -symmetric, the theory of equivariant bifurcations implies that the weakly nonlinear regimes that emerge close to criticality must necessarily take the form of rotating-wave states. These states, previously referred to as frozen wakes in the literature, are thus shown to result from the base-flow symmetry.
The QUEST–La Silla AGN Variability Survey: Connection between AGN Variability and Black Hole Physical Properties

We present our statistical analysis of the connection between active galactic nucleus (AGN) variability and physical properties of the central supermassive black hole (SMBH). We constructed optical light curves using data from the QUEST–La Silla AGN variability survey. To model the variability, we used the structure function, among the excess variance and the amplitude from Damp Random Walk (DRW) modeling. For the measurement of SMBH physical properties, we used public spectra from the Sloan Digital Sky Survey (SDSS). Our analysis is based on an original sample of 2345 sources detected in both SDSS and QUEST–La Silla. For 1473 of these sources we could perform a proper measurement of the spectral and variability properties, and 1348 of these sources were classified as variable (91.5%). We found that the amplitude of the variability (A) depends solely on the rest-frame emission wavelength and the Eddington ratio, where A anticorrelates with both λrest and L/LEdd. This suggests that AGN variability does not evolve over cosmic time, and its amplitude is inversely related to the accretion rate. We found that the logarithmic gradient of the variability (γ) does not correlate significantly with any SMBH physical parameter, since there is no statistically significant linear regression model with an absolute value of the slope higher than 0.1. Finally, we found that the general distribution of γ measured for our sample differs from the distribution of γ obtained for light curves simulated from a DRW process. For 20.6% of the variable sources in our sample, a DRW model is not appropriate to describe the variability, since γ differs considerably from the expected value of 0.5.
Blueshifted [O i] lines from protoplanetary discs: the smoking gun of X-ray photoevaporation

Photoevaporation of protoplanetary discs by high-energy radiation from the central young stellar object is currently the favourite model to explain the sudden dispersal of discs from the inside out. While several theoretical works have provided a detailed pictured of this process, the direct observational validation is still lacking. Emission lines produced in these slow-moving protoplanetary disc winds may bear the imprint of the wind structure and thus provide a potential diagnostic of the underlying dispersal process. In this paper, we primarily focus on the collisionally excited neutral oxygen line at 6300 angstrom. We compare our models predictions to observational data and demonstrate a thermal origin for the observed blueshifted low-velocity component of this line from protoplanetary discs. Furthermore, our models show that while this line is a clear tell-tale sign of a warm, quasi-neutral disc wind, typical of X-ray photoevaporation, its strong temperature dependence makes it unsuitable to measure detailed wind quantities like mass-loss rate.
On the existence of orbits satisfying periodic or conormal boundary conditions for Euler-Lagrange flows

Sei (M,g) eine geschlossene Riemannsche Mannigfaltigkeit, L:TM->R eine Tonelli Lagrange-Funktion. In dieser Dissertation wird die Existenz von Bahnen (die geeignete Randbedingungen erfullen) des zu L assozierten Euler-Lagrange-Flusses untersucht. Es wird erstens nach Bahnen gesucht, die zwei vorgegebene geschlossene Untermannigfaltigkeiten von M verbinden und die \(\textit {konormalen Randbedingungen}\) erfullen: Der fur das Problem relevante Mane kritische Wert wird eingefuhrt, Existenzsatze fur super- und unterkritische Energiewerte werden diskutiert. Durch Gegenbeispiele wird dann gezeigt, dass die Ergebnisse optimal sind. Zweitens wird das Problem der Existenz periodischer Bahnen behandelt: Ein Existenz-Theorem (welches das sogenannte \(\it Lyusternik-Fet-Theorem\) verallgemeinert) wird bewiesen. Schlieslich wird auch ein Satz uber die Anzahl unterschiedlicher periodischer Bahnen fur 2-dimensionale Konfigurationsraume angegeben.
The shape of a memorised random walk

We view random walks as the paths of foraging animals, perhaps searching for food or avoiding predators while forming a mental map of their surroundings. The formation of such maps requires them to memorise the locations they have visited. We model memory using a kernel, proportional to the number of locations recalled as a function of the time since they were first observed. We give exact analytic expressions relating the elongation of the memorised walk to the structure of the memory kernel, and confirm these by simulation. We find that more slowly decaying memories lead to less elongated mental maps.
Magnetic braking of supermassive stars through winds

Context. Supermassive stars (SMSs) are candidates for being progenitors of supermassive quasars at high redshifts. However, their formation process requires strong mechanisms that would be able to extract the angular momentum of the gas that the SMSs accrete. Aims. We investigate under which conditions the magnetic coupling between an accreting SMS and its winds can remove enough angular momentum for accretion to proceed from a Keplerian disc. Methods. We numerically computed the rotational properties of accreting SMSs that rotate at the ΩΓ-limit and estimated the magnetic field that is required to maintain the rotation velocity at this limit using prescriptions from magnetohydrodynamical simulations of stellar winds. Results. We find that a magnetic field of 10 kG at the stellar surface is required to satisfy the constraints on stellar rotation from the ΩΓ-limit. Conclusions. Magnetic coupling between the envelope of SMSs and their winds could allow for SMS formation by accretion from a Keplerian disc, provided the magnetic field is at the upper end of present-day observed stellar fields. Such fields are consistent with primordial origins.
Smooth Factors of Projective Actions of Higher Rank Lattices and Rigidity

We study smooth factors of the standard actions of lattices in higher rank semisimple Lie groups on flag manifolds. Under a mild condition on existence of a single differentiable sink, we show that these factors are $C^{\infty}$-conjugate to the standard actions on flag manifolds.
CORRELATION ANALYSIS OF A LARGE SAMPLE OF NARROW-LINE SEYFERT 1 GALAXIES: LINKING CENTRAL ENGINE AND HOST PROPERTIES

We present a statistical study of a large, homogeneously analyzed sample of narrow-line Seyfert 1 (NLS1) galaxies, accompanied by a comparison sample of broad-line Seyfert 1 (BLS1) galaxies. Optical emission-line and continuum properties are subjected to correlation analyses, in order to identify the main drivers of the correlation space of active galactic nuclei (AGNs), and of NLS1 galaxies in particular. For the first time, we have established the density of the narrow-line region as a key parameter in Eigenvector 1 space, as important as the Eddington ratio L/LEdd. This is important because it links the properties of the central engine with the properties of the host galaxy, i.e., the interstellar medium (ISM). We also confirm previously found correlations involving the line width of Hβ and the strength of the Fe ii and [O iii] λ5007 emission lines, and we confirm the important role played by L/LEdd in driving the properties of NLS1 galaxies. A spatial correlation analysis shows that large-scale environments of the BLS1 and NLS1 galaxies of our sample are similar. If mergers are rare in our sample, accretion-driven winds, on the one hand, or bar-driven inflows, on the other hand, may account for the strong dependence of Eigenvector 1 on ISM density.
Giant plasmon instability in a dual-grating-gate graphene field-effect transistor

We study instability of plasmons in a dual-grating-gate graphene field-effect transistor induced by dc current injection using self-consistent simulations with the Boltzmann equation. With only the acoustic-phonon-limited electron scattering, it is demonstrated that a total growth rate of the plasmon instability, with the terahertz/mid-infrared range of the frequency, can exceed $4\times10^{12}$ s$^{-1}$ at room temperature, which is an order of magnitude larger than in two-dimensional electron gases based on usual semiconductors. By Comparing the simulation results with existing theory, it is revealed that the giant total growth rate originates from simulataneous occurence of the so-called Dyakonov-Shur and Ryzhii-Satou-Shur instabilities.
Nonintrusive Stabilization of Reduced Order Models for Uncertainty Quantification of Time-Dependent Convection-Dominated Flows.

In this paper, we propose a nonintrusive filter-based stabilization of reduced order models (ROMs) for uncertainty quantification (UQ) of the time-dependent Navier-Stokes equations in convection-dominated regimes. We propose a novel high-order ROM differential filter and use it in conjunction with an evolve-filter-relax algorithm to attenuate the numerical oscillations of standard ROMs. We also examine how stochastic collocation methods (SCMs) can be combined with the evolve-filter-relax algorithm for efficient UQ of fluid flows. We emphasize that the new stabilized SCM-ROM framework is nonintrusive and can be easily used in conjunction with legacy flow solvers. We test the new framework in the numerical simulation of a two-dimensional flow past a circular cylinder with a random viscosity that yields a random Reynolds number with mean $Re=100$.
Safety Culture of Physicians’ Medication in Saudi Arabia

Objective: The study aims to demonstrate the Physicians’ Medication Safety Culture in Saudi Arabia.Methods: It examines a cross-sectional survey of physicians' medication safety practices in Saudi Arabia. It self-reported an electronic survey of physicians in Saudi Arabia, ranging from intern to consultant level, and physician specialties. The survey included respondents' demographic information about physicians who reported medication safety items in medical care, as well as medications who executed medication safety. With closed-ended questions, the 5-point Likert response scale system was used. The survey monkey system was used to analyze data on the Physicians’ Medication Safety Culture. In this study, the statistical package for social sciences (SPSS), Jeffery's Amazing Statistics Program (JASP), and Microsoft Excel sheet version 16 were used.Results: The total number of responding physicians was 253, with the majority 73 (54.07 %) coming from the central region, which was statistically significant among the areas (p<0.01). The majority of those who responded were from private hospitals 48(18.97%), MOH hospitals 41(16.21%), and University hospitals 40 (15.81%). Furthermore, 72 (60.50%) were female, while 47 (39.50%) were male, with a statistically significant difference (p<0.01). The average frequency of medications safety items reported monthly in medical care was (5.97), with the highest score element being Medication’s wastage services system (6.42), followed by Medications labelling before use (6.31), Medical drug information resources (6.15) and Medication’s safety committee for medical care (6.11). Anticoagulants 33 (33.33 %) and NSAIDs 32 (32.32 %) were the medications used in medication error reporting. Sedation medications 38(38.78%) and muscle relaxant medications 36 (36.73%) were the drugs used in ADR reporting. Antineoplastic 40 (40.00%) and Anti-seizure drug 39 (39.39%) were the most commonly used medicines in the looks like sound-alike system (38.24 %). Anti-arrhythmic 43 (43.88 %) and anti-psychotic medication 40 (40.40%) were the drugs used in the high alert medication system.Conclusion: The Physicians’ Medication Safety Cultures were inadequate and contradictory. Consequently, the physicians instituted non-serious aspects of medication safety culture. Hence, reviewing aspect medications safety cultures in medical practice with a focus on education and training is strongly advised in Saudi Arabia.
The lex-plus-power inequality for local cohomology modules

We prove an inequality between Hilbert functions of local cohomology modules supported in the homogeneous maximal ideal of standard graded algebras over a field, within the framework of embeddings of posets of Hilbert functions. As a main application, we prove an analogue for local cohomology of Evans' Lex-Plus-Power Conjecture for Betti numbers. This results implies some cases of the classical Lex-Plus-Power Conjecture, namely an inequality between extremal Betti numbers. In particular, for the classes of ideals for which the Eisenbud-Green-Harris Conjecture is currently known, the projective dimension and the Castelnuovo-Mumford regularity of a graded ideal do not decrease by passing to the corresponding Lex-Plus-Power ideal.
Homona spargotis Meyrick, 1910: First report on a Eucalyptus grandis W. Hill × Eucalyptus pellita F. Muell. (Myrtaceae) hybrid in Sumatra, Indonesia (Lepidoptera: Tortricidae)

All potential pests (e.g., defoliating lepidopterans) of Eucalyptus L’Hér. (Myrtaceae) are important to be recorded because of multiple species from this plant genus are ubiquitously planted in forest plantations across the tropics, including Sumatra, Indonesia. The objective of this study was to record, for the first time, a species closest to the avocado leafroller, Homona spargotis Meyrick, 1910 (Lepidoptera: Tortricidae) on a Eucalyptus grandis W. Hill × Eucalyptus pellita F. Muell. hybrid in Sumatra with the insect species identification performed via molecular analysis. The used molecular protocol was able to identify a similar, yet distinct insect species to H. spargotis through analysis of its larvae, which defines its geographical distribution to Sumatra and identified a host species (i.e., E. grandis × E. pellita) for this insect.