Miracle-dz/UniFAR-FTUs huggingface dataset:
The 2XMMi/SDSS Galaxy Cluster Survey - I. The first cluster sample and X-ray luminosity–temperature relation

We present a catalogue of X-ray selected galaxy clusters and groups as a first release of the 2XMMi/SDSS Galaxy Cluster Survey. The survey is a search for galaxy clusters detected serendipitously in observations with XMM-Newton in the footprint of the Sloan Digital Sky Survey (SDSS). The main aims of the survey are to identify new X-ray galaxy clusters, investigate their X-ray scaling relations, identify distant cluster candidates, and study the correlation of the X-ray and optical properties. In this paper, we describe the basic strategy to identify and characterize the X-ray cluster candidates that currently comprise 1180 objects selected from the second XMM-Newton serendipitous source catalogue (2XMMi-DR3). Cross-correlation of the initial catalogue with recently published optically selected SDSS galaxy cluster catalogues yields photometric redshifts for 275 objects. Of these, 182 clusters have at least one member with a spectroscopic redshift from existing public data (SDSS-DR8). We developed an automated method to reprocess the XMM-Newton X-ray observations, determine the optimum source extraction radius, generate source and background spectra, and derive the temperatures and luminosities of the optically confirmed clusters. Here we present the X-ray properties of the first cluster sample, which comprises 175 clusters, among which 139 objects are new X-ray discoveries while the others were previously known as X-ray sources. For each cluster, the catalogue provides: two identifiers, coordinates, temperature, flux [0.5−2] keV, luminosity [0.5−2] keV extracted from an optimum aperture, bolometric luminosity L500 ,t otal massM500 ,r adiusR500, and the optical properties of the counterpart. The first cluster sample from the survey covers a wide range of redshifts from 0.09 to 0.61, bolometric luminosities L500 = 1.9×10 42 −1.2×10 45 erg s −1 , and masses M500 = 2.3×10 13 −4.9×10 14 M� . We extend the relation between the X-ray bolometric luminosity L500 and the X-ray temperature towards significantly lower T and L and still find that the slope of the linear L −T relation is consistent with values published for high luminosities.
The M31 Dwarf Spheroidal Companion Andromeda V: g′, r′, and i′ Imaging with the Gemini Multi-Object Spectrograph on Gemini North

Images obtained in g′, r′, and i′ with the Gemini Multi-Object Spectrograph (GMOS) on Gemini North are used to investigate the metallicity and stellar content of the M31 dwarf spheroidal companion galaxy Andromeda V. Red giant branch (RGB) stars are traced out to radii in excess of 126″ from the galaxy center, indicating that And V extends over a diameter approaching 1 kpc. The mean g′-i′ color of the RGB does not change with radius. Based on the slope of the RGB in the (i′, g′-i′) color-magnitude diagram, we conclude that the metallicity of And V is [Fe/H] = -2.2 ± 0.1. This is lower than earlier estimates and places And V squarely on the relation between metallicity and integrated brightness defined by other dwarf spheroidal and dwarf elliptical galaxies. In contrast to many of the Galaxy's dwarf spheroidal companions, there is no evidence for a statistically significant population of luminous asymptotic giant branch stars near the center of the galaxy.
A toy model for the X-ray spectral variability of active galactic nuclei

Investigations into the long-term X-ray spectral variability of 10 active galactic nuclei (AGNs) revealed a positive spectral index-flux correlation for each object. An inner advection-dominated accretion flow (ADAF) may connect to a thin disc/corona at a certain transition radius. Both these structures are responsible for the hard X-ray emission in AGNs. The ADAF is hot and its X-ray spectrum is hard, while the corona above the disc is relatively cold and its X-ray spectrum is therefore soft. The radiation efficiency of the ADAF is usually much lower than that of the thin disc. An increase in the transition radius may lead to a decrease in the spectral index (i.e. a hard spectrum) and the X-ray luminosity even if the accretion rate is fixed, and a decrease of transition radius leads to an increase in spectral index. We propose that such X-ray variability is caused by a change in the transition radius. Our model calculations can reproduce the observed index-flux correlations, if the transition radius fluctuates around an equilibrium position and the radiation efficiency of ADAFs is similar to 5 per cent of that for a thin disc. The average spectral index-Eddington ratio correlation for these ten AGNs sample can also be reproduced by our model calculations, if the equilibrium transition radius increases with decreasing mass accretion rate.
Probing gravitation with pulsars

Abstract Radio pulsars are fascinating and extremely useful objects. Despite our on-going difficulties in understanding the details of their emission physics, they can be used as precise cosmic clocks in a wide-range of experiments – in particular for probing gravitational physics. While the reader should consult the contributions to these proceedings to learn more about this exciting field of discovering, exploiting and understanding pulsars, we will concentrate here on on the usage of pulsars as gravity labs.
Optimization Modulo Theories

Since ancient times, humanity has sought methods for optimizing their resources and their costs, leading to the study of optimization problems. In this thesis Discrete Optimization Problems are dealt with, which are well-known to have a huge economical impact. In order to tackle these problems, we introduce the Optimization Modulo Theories (OMT) framework, an extension of Satisfiability Modulo Theories (SMT). OMT allows one to model Discrete Optimization Problems as optimization problems of a cost function subject to a quantifier-free first-order formula whose atoms are constraints of Linear Integer Arithmetic (LIA), i.e., linear inequalities over integer variables. Thus, this language exploits the advantages of propositional logic and LIA. Two methods based on the DPLL(T ) approach for SMT are proposed so as to solve problems expressed in OMT: first, by means of an off-the-shelf integer linear programming tool used as a theory solver; and second, by adding new optimization functionalities to satisfiability LIA-solving algorithms originally developed for SMT. Finally, in order to assess the practical value of these approaches, an experimental evaluation has been carried out, whose results are reported in this document.
Phase transition and critical behavior of d=3 chiral fermion models with left/right asymmetry

We investigate the critical behavior of three-dimensional relativistic fermion models with a U(N{sub L}){sub L} x U(1){sub R} chiral symmetry reminiscent of the Higgs-Yukawa sector of the standard model of particle physics. We classify all possible four-fermion interaction terms and the corresponding discrete symmetries. For sufficiently strong correlations in a scalar parity-conserving channel, the system can undergo a second-order phase transition to a chiral-symmetry broken phase, which is a 3d analog of the electroweak phase transition. We determine the critical behavior of this phase transition in terms of the critical exponent {nu} and the fermion and scalar anomalous dimensions for N{sub L{>=}}1. Our models define new universality classes that can serve as prototypes for studies of strongly correlated chiral fermions.
SN 2009bb: A PECULIAR BROAD-LINED TYPE Ic SUPERNOVA,

Ultraviolet, optical, and near-infrared photometry and optical spectroscopy of the broad-lined Type Ic supernova (SN) 2009bb are presented, following the flux evolution from −10 to +285 days past B-band maximum. Thanks to the very early discovery, it is possible to place tight constraints on the SN explosion epoch. The expansion velocities measured from near maximum spectra are found to be only slightly smaller than those measured from spectra of the prototype broad-lined SN 1998bw associated with GRB 980425. Fitting an analytical model to the pseudobolometric light curve of SN 2009bb suggests that 4.1 ± 1.9 M☉ of material was ejected with 0.22 ± 0.06 M☉ of it being 56Ni. The resulting kinetic energy is 1.8 ± 0.7 × 1052 erg. This, together with an absolute peak magnitude of MB = −18.36 ± 0.44, places SN 2009bb on the energetic and luminous end of the broad-lined Type Ic (SN Ic) sequence. Detection of helium in the early time optical spectra accompanied with strong radio emission and high metallicity of its environment makes SN 2009bb a peculiar object. Similar to the case for gamma-ray bursts (GRBs), we find that the bulk explosion parameters of SN 2009bb cannot account for the copious energy coupled to relativistic ejecta, and conclude that another energy reservoir (a central engine) is required to power the radio emission. Nevertheless, the analysis of the SN 2009bb nebular spectrum suggests that the failed GRB detection is not imputable to a large angle between the line-of-sight and the GRB beamed radiation. Therefore, if a GRB was produced during the SN 2009bb explosion, it was below the threshold of the current generation of γ-ray instruments.
Spin-density-wave transition of Fe1 zigzag chains and metamagnetic transition of Fe2 in TaFe1+yTe3

We systematically study the AFM order of Fe1 zigzag chains and spin-flop of excess Fe2 under high magnetic field H through the susceptibility, magnetoresistance (MR), Hall effect and specific heat measurements in high-quality single crystal TaFe$_{1+y}$Te$_3$. These properties suggest that the high temperature AFM transition of the TaFeTe$_3$ layers should be a SDW-type AFM order. Below T$_N$, Fe1 antiferromangetic zigzag chains will induce a inner magnetic field \textbf{H$_{int}$} to interstitial Fe2 and lead Fe2 also forms an AFM alignment, in which the magnetic coupling strength between Fe1 and Fe2 is enhanced by decreasing temperature. On the other hand, the external magnetic field \textbf{H$_{ext}$} inclines to tune interstitial Fe2 to form FM alignment along \textbf{H$_{ext}$}. When \textbf{H$_{ext}$} arrives at the "coercive" field H$_C$, which is able to break the coupling between Fe1 and Fe2, these interstitial Fe2 atoms take a spin-flop from AFM to FM alignment. The local moment of Fe2 is about 4 $\mu_{\textrm{B}}$/Fe. From low field ($ $H$_C$) FM for Fe2, it also induces sharp drop on resistivity and an anomalous Hall effect. The possible magnetic structure of TaFe$_{1+y}$Te$_3$ is proposed from the susceptibility and MR. The properties related to the spin-flop of Fe2 supply a good opportunity to study the coupling between Fe1 and Fe2 in these TaFe$_{1+y}$Te$_3$ or Fe$_{1+y}$Te with interstitial Fe2 compounds.
Brightest cluster galaxies in cosmological simulations with adaptive mesh refinement: successes and failures

ABSTRACT A large sample of cosmological hydrodynamical zoom-in simulations with Adap-tive Mesh Reﬁnement (AMR) is analysed to study the properties of simulated Bright-est Cluster Galaxies (BCGs). Following the formation and evolution of BCGs requiresmodeling an entire galaxy cluster, because the BCG properties are largely inﬂuencedby the state of the gas in the cluster and by interactions and mergers with satellites.BCG evolution is also deeply inﬂuenced by the presence of gas heating sources suchas Active Galactic Nuclei (AGNs) that prevent catastrophic cooling of large amountsof gas. We show that AGN feedback is one of the most important mechanisms inshaping the properties of BCGs at low redshift by analysing our statistical sample ofsimulations with and without AGN feedback. When AGN feedback is included BCGmasses, sizes, star formation rates and kinematic properties are closer to those of theobserved systems. Some small discrepancies are observed only for the most massiveBCGs, an eﬀect that might be due to physical processes that are not included in ourmodel.Keywords: black hole physics – cosmology:theory – cosmology:large-scalestructureof Universe – galaxies: formation – galaxies: clusters: general – methods: numerical
Symmetries and Strings in Field Theory and Gravity

We discuss aspects of global and gauged symmetries in quantum field theory and quantum gravity, focusing on discrete gauge symmetries. An effective Lagrangian description of Zp gauge theories shows that they are associated with an emergent Zp one-form (KalbRamond) gauge symmetry. This understanding leads us to uncover new observables and new phenomena in nonlinear σ-models. It also allows us to expand on Polchinski’s classification of cosmic strings. We argue that in models of quantum gravity, there are no global symmetries, all continuous gauge symmetries are compact, and all charges allowed by Dirac quantization are present in the spectrum. These conjectures are not new, but we present them from a streamlined and unified perspective. Finally, our discussion about string charges and symmetries leads to a more physical and more complete understanding of recently found consistency conditions of supergravity.
Fully Distributed Adaptive Formation Tracking for Directed Heterogeneous Multi-Agent Systems With Unknown Input

In this brief, the time-varying output formation tracking (TVOFT) problem for directed multi-agent systems is studied, where the leader has unknown input and each follower has nonidentical dynamics. The main object of this brief is to construct fully distributed controller so that the outputs of followers track the leader’s output and realize the expected formation simultaneously. Firstly, by exploiting the neighboring information and local estimation, two kinds of adaptive observers are, respectively, constructed to estimate the states of the leader and followers, which do not require the bound of leader’s unknown input. Then, by using the distributed observers and the expected time-varying formation vector, a TVOFT control protocol is developed in a fully distributed form, and the parameters of the controller are designed by an algorithm including three steps. Furthermore, on the basis of the Lyapunov stability theory and output regulation method, the TVOFT criteria for the considered closed-loop multi-agent systems are obtained on the basis of the presented control protocol. At last, in order to illustrate the theoretical results, a simulation example is given.
Optical trapping of ultracold dysprosium atoms: transition probabilities, dynamic dipole polarizabilities and van der Waals C6 coefficients

The efficiency of the optical trapping of ultracold atoms depends on the atomic dynamic dipole polarizability governing the atom-field interaction. In this article, we have calculated the real and imaginary parts of the dynamic dipole polarizability of dysprosium in the ground and first excited levels. Due to the high electronic angular momentum of those two states, the polarizabilities possess scalar, vector and tensor contributions that we have computed, on a wide range of trapping wavelengths, using the sum-over-state formula. Using the same formalism, we have also calculated the C6 coefficients characterizing the van der Waals interaction between two dysprosium atoms in the two lowest levels. We have computed the energies of excited states and the transition probabilities appearing in the sums, using a combination of ab initio and least-square-fitting techniques provided by the Cowan codes and extended in our group. Regarding the real part of the polarizability, for field frequencies far from atomic resonances, the vector and tensor contributions are two-orders-of-magnitude smaller than the scalar contribution, whereas for the imaginary part, the vector and tensor contributions represent a noticeable fraction of the scalar contribution. Finally, our anisotropic C6 coefficients are much smaller than those published in the literature.
Perimyocarditis presenting as thoracic spinal pain in a physiotherapy outpatient clinic – a case report

Abstract Objective To highlight the necessity for on-going vigilance of serious pathology when assessing and managing people with spinal pain. Methods A case report of a young male patient who sought physiotherapy treatment for his acute thoracic pain. Following physiotherapy assessment, it seemed unlikely that the pain was related to a musculoskeletal problem. Besides pain-induced vomiting, there were no overt signs of serious pathology. However, he had a family history of cardiac issues. The patient was referred back to his general practitioner (GP) for further assessment. Results The patient was subsequently diagnosed with perimyocarditis following investigations and was treated accordingly. At 6, 12 and 24 months follow-up, he reported good health. Conclusions and impact statement Physiotherapists must remain vigilant of serious pathology even if patients have been examined by other healthcare professionals. This case also raises the issue of whether ‘vascular profiling’ should be part of routine practice protocols.
Integral-field spectroscopy of (90482) Orcus-Vanth

Aims. We seek to constrain the surface composition of the trans-Neptunian object (90482) Orcus and its small satellite Vanth, as well as their mass and density. Methods. We acquired near-infrared spectra (1.4−2.4 μm) of (90482) Orcus and its companion Vanth using the adaptive-optics-fed integral-field spectrograph SINFONI mounted on Yepun/UT4 at the European Southern Observatory Very Large Telescope. We took advantage of a very favorable appulse (separation of only 4 �� ) between Orcus and the UCAC2 29643541 star (mR = 11.6) to use the adaptive optics mode of SINFONI, allowing both components to be spatially resolved and Vanth colors to be extracted independently from Orcus. Results. The spectrum of Orcus we obtain has the highest signal-to-noise ratio to date, and we confirm the presence of H2 Oi ce in crystalline form, together with the presence of an absorption band at 2.2 μm. We set an upper limit of about 2% to the presence of methane, and 5% for ethane. Since the methane alone cannot account for the 2.2 μm band, the presence of ammonia is suggested to the level of a couple of percent. The colors of Vanth are found to be slightly redder than those of Orcus, but the large measurement uncertainties prevent us from drawing any firm conclusions about the origin of the pair (capture or co-formation). Finally, we reset the orbital phase of Vanth around Orcus, and confirm the orbital parameters derived by Brown and collaborators.
A Systematic Review of Antibiotic Resistance Trends and Treatment Options for Hospital-Acquired Multidrug-Resistant Infections

Antimicrobial resistance is a major public health challenge described by the World Health Organization as one of the top 10 public health challenges worldwide. Drug-resistant microbes contribute significantly to morbidity and mortality in the hospital, especially in the critical care unit. The primary etiology of increasing antibiotic resistance is inappropriate and excessive use of antibiotics. The alarming rise of drug-resistant microbes worldwide threatens to erode our ability to treat infections with our current armamentarium of antibiotics. Unfortunately, the pace of development of new antibiotics by the pharmaceutical industry has not kept up with rising resistance to expand our options to treat microbial infections. The costs of antibiotic resistance include death and disability, extended hospital stays due to prolonged sickness, need for expensive therapies, rising healthcare expenditure, reduced productivity from time out of the workforce, and rising penury. This review sums up the common mechanisms, trends, and treatment options for hospital-acquired multidrug-resistant microbes.
Classification of Power Quality Disturbances using Wavelet Packet Information Entropy Feature Vectors and Probabilistic Neural Network

: This paper illustrates the automatic recognition of power quality disturbances (PQDs) using Wavelet Packet Tuned Probabilistic Neural Network ( WP-PNN ) structure. Eight statistical parameters are extracted from the WP by decomposing a signal into the fourth level. The PNN is simulated with these statistical parameters for performance appraisal. The Information Gain (IG) feature selection algorithm has been applied to rank the feature subsets based on high IG entropy. 16 significant WP-IG features are extracted from 128 features computed from the WP statistical coefficients. The objective is to discard redundant data for better accuracy and lower computational complexity. A two-stage experimental analysis has been carried out to validate the WP-IGPNN structure. Initially, t he PQ data set is procured by regularly varying the parameters of mathematical models and choosing the best features using IG to experience the highest accuracy. Finally, the coefficient values which are not chosen in the earlier case have been used to generate a new data set. The classification accuracy has been observed using the new data set with the same chosen feature set as used in the first stage. The noisy signals are also investigated to simulate the classifier to validate the proposed WP-IGPNN structure.
THE EFL TEACHERS’ PERCEPTIONS OF LEARNER AUTONOMY AND ITS DEVELOPMENT IN AN INDONESIAN CONTEXT

Creating long-life learners has become a long-term educational goal in many educational settings including Indonesia. An initial step towards this goal is to develop autonomy in students. Currently, learner autonomy or independence in learning has been promoted in higher education through the concept of Merdeka Belajar (freedom of learning) by the Minister of Education and Culture. In high schools, the 2013 curriculum has also emphasized learner autonomy development. Thus it is necessary to look back at how teachers perceived the concept of learner autonomy long before the concept of Merdeka Belajar was introduced. This article reports a quantitative study that investigated English teachers’ perceptions of learner autonomy and its development in Indonesia. This study was conducted in 2014 using a questionnaire and involved 145 high school English teachers in Magelang Regency, Central Java, Indonesia. The findings revealed that these Indonesian teachers held positive perceptions of learner autonomy and strongly supported psychological elements of learner autonomy. These EFL teachers also showed strong support for social aspects of autonomy. These junior high school teachers perceived social interaction and cooperation as important for promoting learner autonomy in the Indonesian context.