Miracle-dz/UniFAR-FTUs huggingface dataset:
Chemodynamical evolution of tidal dwarf galaxies – II. The long-term evolution and influence of a tidal field

In a series of papers, we present detailed chemo-dynamical simulations of tidal dwarf galaxies (TDGs). After the first paper, where we focused on the very early evolution, we present in this work simulations on the long-term evolution of TDGs, ranging from their formation to an age of 3 Gyr. Dark-matter free TDGs may constitute a significant component of the dwarf galaxy (DG) population. But it remains to be demonstrated that TDGs can survive their formation phase given stellar feedback processes, the time-variable tidal field of the post-encounter host galaxy and its dark matter halo and ram-pressure wind from the gaseous halo of the host. For robust results the maximally damaging feedback by a fully populated invariant stellar IMF in each star cluster is assumed, such that fractions of massive stars contribute during phases of low star-formation rates. The model galaxies are studied in terms of their star-formation history, chemical enrichment and rotational curves. All models evolve into a self-regulated long-term equilibrium star-formation phase lasting for the full simulation time, whereby the TDGs become significantly more compact and sustain significantly higher SFRs through compressive tides than the isolated model. None of the models is disrupted despite the unphysical extreme feedback, and none of the rotation curves achieves the high values observed in real TDGs, despite non-virial gas accretion phases.
CLOSE COMPANIONS TO YOUNG STARS. I. A LARGE SPECTROSCOPIC SURVEY IN CHAMAELEON I AND TAURUS-AURIGA

We present the results of a multiplicity survey of 212 T Tauri stars in the Chamaeleon I and Taurus-Auriga star-forming regions, based on high-resolution spectra from the Magellan Clay 6.5 m telescope. From these data, we achieved a typical radial velocity (RV) precision of ∼80 m s−1 with slower rotators yielding better precision, in general. For 174 of these stars, we obtained multi-epoch data with sufficient time baselines to identify binaries based on RV variations. We identified eight close binaries and four close triples, of which three and two, respectively, are new discoveries. The spectroscopic multiplicity fractions we find for Chamaeleon I (7%) and Taurus-Auriga (6%) are similar to each other, and to the results of field star surveys in the same mass and period regime. However, unlike the results from imaging surveys, the frequency of systems with close companions in our sample is not seen to depend on primary mass. Additionally, we do not find a strong correlation between accretion and close multiplicity. This implies that close companions are not likely the main source of the accretion shut down observed in weak-lined T Tauri stars. Our results also suggest that sufficient RV precision can be achieved for at least a subset of slowly rotating young stars to search for hot Jupiter planets.
The environments of Ly α blobs – I. Wide-field Ly α imaging of TN J1338−1942, a powerful radio galaxy at z ≃ 4.1 associated with a giant Ly α nebula

We exploit wide-field Ly α imaging with Subaru to probe the environment around TN J1338−1942, a powerful radio galaxy with a > 100 kpc Ly α halo at z = 4.11. We used a sample of Ly α emitters (LAEs) down to log (LLyα[ erg s−1]) ∼ 42.8 to measure the galaxy density around TN J1338−1942, compared to a control sample from a blank field taken with the same instrument. We found that TN J1338−1942 resides in a region with a peak overdensity of δLAE = 2.8 ± 0.5 on scales of 8 h− 1 Mpc (on the sky) and 112 h− 1 Mpc (line of sight) in comoving coordinates. Adjacent to this overdensity, we found a strong underdensity where virtually no LAEs are detected. We used a semi-analytical model of LAEs derived from the Millennium Simulation to compare our results with theoretical predictions. While the theoretical density distribution is consistent with the blank field, overdense regions such as that around TN J1338−1942 are very rare, with a number density of 6.4 × 10− 8 Mpc− 3 (comoving), corresponding to the densest <0.4 percentile at z ≃ 4.1. We also found that the Ly α luminosity function in the TN J1338−1942 field differs from that in the blank field: the number of bright LAEs (log (LLyα[ erg s− 1]) ≳ 43.3) is enhanced, while the number of fainter LAEs is relatively suppressed. These results suggest that some powerful radio galaxies associated with Ly α nebulae reside in extreme overdensities on ∼3–6 Mpc scales, where star formation and AGN activity may be enhanced via frequent galaxy mergers or high rates of gas accretion from the surroundings.
Nonperturbative interpretation of the Bloch vector's path beyond the rotating-wave approximation

The Bloch vector's path of a two-level system exposed to a monochromatic field exhibits, in the regime of strong coupling, complex corkscrew trajectories. By considering the infinitesimal evolution of the two-level system when the field is treated as a classical object, we show that the Bloch vector's rotation speed oscillates between zero and twice the rotation speed predicted by the rotating wave approximation. Cusps appear when the rotation speed vanishes. We prove analytically that in correspondence to cusps the curvature of the Bloch vector's path diverges. On the other hand, numerical data show that the curvature is very large even for a quantum field in the deep quantum regime with mean number of photons $\bar{n}\lesssim 1$. We finally compute numerically the typical error size in a quantum gate when the terms beyond rotating wave approximation are neglected.
From Rindler space to the electromagnetic energy-momentum tensor of a Casimir apparatus in a weak gravitational field

This paper studies two perfectly conducting parallel plates in the weak gravitational field on the surface of the Earth. Since the appropriate line element, to first order in the constant gravity acceleration g, is precisely of the Rindler type, we can exploit the formalism for studying Feynman Green functions in Rindler spacetime. Our analysis does not reduce the electromagnetic potential to the transverse part before quantization. It is instead fully covariant and well suited for obtaining all components of the regularized and renormalized energy-momentum tensor to arbitrary order in the gravity acceleration g. The general structure of the calculation is therefore elucidated, and the components of the Maxwell energy-momentum tensor are evaluated up to second order in g, improving a previous analysis by the authors and correcting their old first-order formula for the Casimir energy.
Lie algebras admitting symmetric, invariant and nondegenerate bilinear forms

We present structural properties of Lie algebras admitting symmetric, invariant and nondegenerate bilinear forms. We show that these properties are not satisfied by nilradicals of parabolic subalgebras of real split forms of complex simple Lie algebras, neither by 2-step nilpotent Lie algebras associated with graphs, with only few exceptions. These rare cases are, essentially, abelian Lie algebras, the free 3-step nilpotent Lie algebra on 2-generators and the free 2-step nilpotent Lie algebra on 3-generators.
Probing quantum and classical turbulence analogy through global bifurcations in a von K\'arm\'an liquid Helium experiment

SHREK Collaboration: B. Saint-Michel, E. Herbert, J. Salort, C. Baudet, M. Bon Mardion, P. Bonnay, M. Bourgoin, B. Castaing, L. Chevillard, F. Daviaud, P. Diribarne, B. Dubrulle, Y. Gagne, M. Gibert, A. Girard, B. Hébral, Th. Lehner, and B. Rousset Laboratoire SPHYNX, CEA/IRAMIS/SPEC, CNRS URA 2464, F-91191 Gif-sur-Yvette, France Laboratoire FAST, CNRS UMR 7608, Université Paris-Sud, Université Pierre-et-Marie-Curie, Bât. 502, Campus universitaire, 91405 Orsay, France Laboratoire de Physique de l’ÉNS de Lyon, CNRS/Université Lyon F-69364 Lyon cedex 7, France Laboratoire des Écoulements Géophysiques et Industriels, CNRS/UJF/INPG, F-38041 Grenoble Cedex 9, France Service des Basses Températures, INAC/SBT, UMR CEA-UJF 9004, CEA Grenoble, 17 rue des Martyrs 38054 Grenoble Cedex France Université Grenoble Alpes, Institut NÉEL, F-38042 Grenoble, France, CNRS, Institut NÉEL, F-38042 Grenoble, France LUTH, Observatoire Paris-Meudon, 5 Pl. Jules Janssen, F-92195 Meudon Cedex, France
Hadronization, spin, and lifetimes

Measurements of lifetimes can be done in two ways. For very short lived particles, the width can be measured. For long lived ones, the lifetime can be directly measured, for example, using a displaced vertex. Practically, the lifetime cannot be extracted for particles with intermediate lifetimes. We show that for such cases information about the lifetime can be extracted for heavy colored particles that can be produced with known polarization. For example, a t-like particle with intermediate lifetime hadronizes into a superposition of the lowest two hadronic states, T* and T (the equivalent of B* and B). Depolarization effects are governed by time scales that are much longer than the hadronization time scale, ΛQCD−1. After a time of order 1/Δm, with Δm≡m(T*)−m(T), half of the initial polarization is lost. The polarization is totally lost after a time of order 1/Γγ, with Γγ = Γ(T* → Tγ). Thus, by comparing the initial and final polarization, we get information on the particle's lifetime.
Three-dimensional dynamic cutting model

The determination of a dynamic law of cut is complex and often very difficult to develop. Several formulations were developed, in very complex ways being given that 3 AD crosses from there, the number of variables is much higher than out of orthogonal cut. The existence of the plan of displacements and the correlations with the elastic characteristics of the machining system thus make it possible to simplify the dynamic model 3D. A dynamic model is proposed on the basis of experimental approach. Simulation is in concord with the experimental results.
Articulation Timing and Orthographical Representation of Consonant Gemination in Sinhala

Consonant gemination, in general, has two major aspects: either lengthening or doubling the pronunciation of the consonant. This study mainly focuses on articulation and orthography in Sinhala, the two parts of the language where consonant gemination occurs. It examines the pronunciation time ratios of 16 pairs of singleton and geminated Sinhala consonants in order to analyze the relationship that exists between their articulation and orthography. The research problem was stated as ‘what relationship is dis closed by the articulation time ratios and orthography of consonant gemination in Sinhala’. To answer it, the articulation timings of the singleton and geminated consonants were measured with the ratios between them being calculated. Then, as the second step, the ratios and the orthographic symbolization were compared and contrasted. A group of ten adult participants contributed to the data: five males and five females. Praat.exe was the main technical instrument used to measure pronunciation timings. The data revealed that the ratios lie between a minimum of 1:1.6 and a maximum of 1:2.4 times. Therefore, consonant gemination in Sinhala is a lengthening process. Moreover, the alpha-syllabic writing system ignores the length ratios of the geminated consonants .
Gammapy - A Python package for {\gamma}-ray astronomy

In the past decade imaging atmospheric Cherenkov telescope arrays such as H.E. S.S. , MAGIC, VERITAS, as well as the Fermi-LAT space telescope have provided us with detailed images and spectra of the gamma-ray universe for the first time. Currently the gamma-ray community is preparing to build the next-generation Cherenkov Telecope Array (CTA), which will be operated as an open observatory. Gammapy (available at this https URL under the open-source BSD license) is a new in-development Astropy affiliated package for high-level analysis and simulation of astronomical gamma-ray data. It is built on the scientific Python stack (Numpy, Scipy, matplotlib and scikit-image) and makes use of other open-source astronomy packages such as Astropy, Sherpa and Naima to provide a flexible set of tools for gamma-ray astronomers. We present an overview of the current Gammapy features and example analyses on real as well as simulated gamma-ray datasets. We would like Gammapy to become a community-developed project and a place of collaboration between scientists interested in gamma-ray astronomy with Python. Contributions welcome!
NEW EXTENDED DEUTERIUM FRACTIONATION MODEL: ASSESSMENT AT DENSE ISM CONDITIONS AND SENSITIVITY ANALYSIS

Observations of deuterated species are useful in probing the temperature, ionization level, evolutionary stage, chemistry, and thermal history of astrophysical environments. The analysis of data from the Atacama Large Millimeter Array and other new telescopes requires an elaborate model of deuterium fractionation. This paper presents a publicly available chemical network with multi-deuterated species and an extended, up-to-date set of gas-phase and surface reactions. To test this network, we simulate deuterium fractionation in diverse interstellar sources. Two cases of initial abundances are considered: (1) atomic except for H2 and HD, and (2) molecular from a prestellar core. We reproduce the observed D/H ratios of many deuterated molecules, and sort the species according to their sensitivity to temperature gradients and initial abundances. We find that many multiply deuterated species produced at 10 K retain enhanced D/H ratios at temperatures ≲ 100 K. We study how recent updates to reaction rates affect calculated D/H ratios, and perform a detailed sensitivity analysis of the uncertainties of the gas-phase reaction rates in the network. We find that uncertainties are generally lower in dark cloud environments than in warm infrared dark clouds and that uncertainties increase with the size of the molecule and number of D-atoms. A set of the most problematic reactions is presented. We list potentially observable deuterated species predicted to be abundant in low- and high-mass star-formation regions.
Semiclassical orthogonal polynomial systems on nonuniform lattices, deformations of the Askey table, and analogues of isomonodromy

Abstract A 𝔻-semiclassical weight is one which satisfies a particular linear, first-order homogeneous equation in a divided-difference operator 𝔻. It is known that the system of polynomials, orthogonal with respect to this weight, and the associated functions satisfy a linear, first-order homogeneous matrix equation in the divided-difference operator termed the spectral equation. Attached to the spectral equation is a structure which constitutes a number of relations such as those arising from compatibility with the three-term recurrence relation. Here this structure is elucidated in the general case of quadratic lattices. The simplest examples of the 𝔻-semiclassical orthogonal polynomial systems are precisely those in the Askey table of hypergeometric and basic hypergeometric orthogonal polynomials. However within the 𝔻-semiclassical class it is entirely natural to define a generalization of the Askey table weights which involve a deformation with respect to new deformation variables. We completely construct the analogous structures arising from such deformations and their relations with the other elements of the theory. As an example we treat the first nontrivial deformation of the Askey–Wilson orthogonal polynomial system defined by the q-quadratic divided-difference operator, the Askey–Wilson operator, and derive the coupled first-order divided-difference equations characterizing its evolution in the deformation variable. We show that this system is a member of a sequence of classical solutions to the q-Painlevé system.
Entanglement-breaking channels and entanglement sudden death

The occurrence of entanglement sudden death in the evolution of a bipartite system depends on both the initial state and the channel responsible for the evolution. An extreme case is that of entanglement braking channels, which are channels that acting on only one of the subsystems drives them to full disentanglement regardless of the initial state. In general, one can find certain combinations of initial states and channels acting on one or both subsystems that can result in entanglement sudden death or not. Neither the channel nor the initial state, but their combination, is responsible for this effect, but their combination. In this work we show that, in all cases, when entanglement sudden death occurs, the evolution can be mapped to that of an effective entanglement breaking channel on a modified initial state. Our results allow to anticipate which states will suffer entanglement sudden death or not for a given evolution. An experiment with polarization entangled photons demonstrates the utility of this result in a variety of cases.
Flexible and biocompatible microelectrode arrays fabricated by supersonic cluster beam deposition on SU-8

We fabricated highly adherent and electrically conductive micropatterns on SU-8 by supersonic cluster beam deposition (SCBD). This technique is based on the aerodynamical acceleration of neutral metallic nanoparticles produced in the gas phase. The kinetic energy acquired by the nanoparticles allows implantation in an SU-8 layer, thus producing a metal–polymer nanocomposite thin layer. The nanocomposite shows ohmic electrical conduction and it can also be used as an adhesion layer for further metallization with a metallic overlayer. We characterized the electrical conduction, adhesion and biocompatibility of microdevices obtained by SCBD on SU-8 demonstrating the compatibility of our approach with standard lift-off technology on 4″ wafer. A self-standing and flexible microelectrode array has been produced. Cytological tests with neuronal cell lines demonstrated improved cell growth on the nanocomposite layer.
The photospheric solar oxygen project: IV. 3D-NLTE investigation of the 777 nm triplet lines

The solar photospheric oxygen abundance is still widely debated. Adopting the solar chemical composition based on the "low" oxygen abundance, as determined with the use of three-dimensional (3D) hydrodynamical model atmospheres, results in a well-known mismatch between theoretical solar models and helioseismic measurements that is so far unresolved. We carry out an independent redetermination of the solar oxygen abundance by investigating the center-to-limb variation of the OI IR triplet lines at 777 nm in different sets of spectra with the help of detailed synthetic line profiles based on 3D hydrodynamical CO5BOLD model atmospheres and 3D non-LTE line formation calculations with NLTETD. The idea is to simultaneously derive the oxygen abundance,A(O), and the scaling factor SH that describes the cross-sections for inelastic collisions with neutral hydrogen relative the classical Drawin formula. The best fit of the center-to-limb variation of the triplet lines achieved with the CO5BOLD 3D solar model is clearly of superior quality compared to the line profile fits obtained with standard 1D model atmospheres. Our best estimate of the 3D non-LTE solar oxygen abundance is A(O) = 8.76 +/- 0.02, with the scaling factor SH in the range between 1.2 and 1.8. All 1D non-LTE models give much lower oxygen abundances, by up to -0.15 dex. This is mainly a consequence of the assumption of a $\mu$-independent microturbulence.
Head-on collision of multistate ultralight BEC dark matter configurations

Density profiles of ultralight Bose-Condensate dark matter inferred from numerical simulations of structure formation, ruled by the Gross-Pitaevskii-Poisson (GPP) system of equations, have a core-tail structure. Multi-state equilibrium configurations of the GPP system on the other hand, have a similar core-tail density profile. We now submit these multi-state configurations to highly dynamical scenarios and show their potential as providers of appropriate density profiles of structures. What we do is to present the simulation of head-on collisions between two equilibrium configurations of the GPP system of equations, including the collision of ground state with multi-state configurations. We study the regimes of solitonic and merger behavior, and show generic properties of the dynamics of the system, including the relaxation process and attractor density profiles. We show the merger of multi-state configurations have the potential to produce core-tail density profiles, with the core dominated by the ground state and a halo dominated by an additional states.
An autoencoder of stellar spectra and its application in automatically estimating atmospheric parameters

This article investigates the problem of estimating stellar atmospheric parameters from spectra. Feature extraction is a key procedure in estimating stellar parameters automatically. We propose a scheme for spectral feature extraction and atmospheric parameter estimation using the following three procedures: firstly, learn a set of basic structure elements (BSE) from stellar spectra using an autoencoder; secondly, extract representative features from stellar spectra based on the learned BSEs through some procedures of convolution and pooling; thirdly, estimate stellar parameters ($T_{eff}$, log$~g$, [Fe/H]) using a back-propagation (BP) network. The proposed scheme has been evaluated on both real spectra from Sloan Digital Sky Survey (SDSS)/Sloan Extension for Galactic Understanding and Exploration (SEGUE) and synthetic spectra calculated from Kurucz's new opacity distribution function (NEWODF) models. The best mean absolute errors (MAEs) are 0.0060 dex for log$~T_{eff}$, 0.1978 dex for log$~g$ and 0.1770 dex for [Fe/H] for the real spectra and 0.0004 dex for log$~T_{eff}$, 0.0145 dex for log$~g$ and 0.0070 dex for [Fe/H] for the synthetic spectra.
Bioinformatics Predicted Linear Epitopes of the Major Coat Protein of the Beet Yellows Virus for Detection of the Virus in the Cell Extract of the Infected Plant

Beet yellows virus, which belongs to the genus Closterovirus, family Closteroviridae and has a significant negative economic impact, has proven to be challenging to detect and diagnose. To obtain antibodies against BYV, we propose an easier bioinformatics approach than the isolation and purification of the wild virus as an antigen. We used the SWISS-MODEL Workspace (Biozentrum Basel) protein 3D prediction program to discover epitopes of major coat protein p22 lying on the surface of the BYV capsid. Sequences coding these epitopes were cloned into plasmid pQE-40 (Qiagen) in frame with mouse dihydrofolate reductase gene. Fused epitopes were expressed in Escherichia coli and isolated by the Ni-NTA affinity chromatography. Murine antibodies were raised against each epitope and in a combination of both and characterized by dot-ELISA and indirect ELISA. We successively used these antibodies for diagnosis of virus disease in systemically infected Tetragonia tetragonioides. We believe the approach described above can be used for diagnostics of difficult-to-obtain and hazardous-to-health viral infections.