Miracle-dz/UniFAR-FTUs huggingface dataset:
Reconstructing the metric of the local Universe from number counts observations

Number counts observations available with new surveys such as the Euclid mission will be an important source of information about the metric of the Universe. We compute the low red-shift expansion for the energy density and the density contrast using an exact spherically symmetric solution in presence of a cosmological constant. At low red-shift the expansion is more precise than linear perturbation theory prediction. We then use the local expansion to reconstruct the metric from the monopole of the density contrast. We test the inversion method using numerical calculations and find a good agreement within the regime of validity of the red-shift expansion. The method could be applied to observational data to reconstruct the metric of the local Universe with a level of precision higher than the one achievable using perturbation theory.
Recoiling supermassive black hole escape velocities from dark matter haloes

We simulate recoiling black hole trajectories from z = 20 to z = 0 in dark matter haloes, quantifying how parameter choices affect escape velocities. These choices include the strength of dynamical friction, the presence of stars and gas, the accelerating expansion of the Universe (Hubble acceleration), host halo accretion and motion, and seed black hole mass. Lambda cold dark matter halo accretion increases escape velocities by up to 0.6 dex and significantly shortens return time-scales compared to non-accreting cases. Other parameters change orbit damping rates but have subdominant effects on escape velocities;dynamical friction is weak at halo escape velocities, even for extreme parameter values. We present formulae for black hole escape velocities as a function of host halo mass and redshift. Finally, we discuss how these findings affect black hole mass assembly as well as minimum stellar and halo masses necessary to retain supermassive black holes.
Fast Vortex Oscillations in a Ferrimagnetic Disk near the Angular Momentum Compensation Point

We theoretically study the oscillatory dynamics of a vortex core in a ferrimagnetic disk near its angular momentum compensation point, where the spin density vanishes but the magnetization is finite. Due to the finite magnetostatic energy, a ferrimagnetic disk of suitable geometry can support a vortex as a ground state similar to a ferromagnetic disk. In the vicinity of the angular momentum compensation point, the dynamics of the vortex resemble those of an antiferromagnetic vortex, which is described by equations of motion analogous to Newton's second law for the motion of particles. Owing to the antiferromagnetic nature of the dynamics, the vortex oscillation frequency can be an order of magnitude larger than the frequency of a ferromagnetic vortex, amounting to tens of GHz in common transition-metal based alloys. We show that the frequency can be controlled either by applying an external field or by changing the temperature. In particular, the latter property allows us to detect the angular momentum compensation temperature, at which the lowest eigenfrequency attains its maximum, by performing FMR measurements on the vortex disk. Our work proposes a ferrimagnetic vortex disk as a tunable source of fast magnetic oscillations and a useful platform to study the properties of ferrimagnets.
Evolution of Morphological and Physical Properties of Laboratory Interstellar Organic Residues with Ultraviolet Irradiation

Refractory organic compounds formed in molecular clouds are among the building blocks of the solar system objects and could be the precursors of organic matter found in primitive meteorites and cometary materials. However, little is known about the evolutionary pathways of molecular cloud organics from dense molecular clouds to planetary systems. In this study, we focus on the evolution of the morphological and viscoelastic properties of molecular cloud refractory organic matter. We found that the organic residue, experimentally synthesized at ∼10 K from UV-irradiated H2O-CH3OH-NH3 ice, changed significantly in terms of its nanometer- to micrometer-scale morphology and viscoelastic properties after UV irradiation at room temperature. The dose of this irradiation was equivalent to that experienced after short residence in diffuse clouds (≤104 years) or irradiation in outer protoplanetary disks. The irradiated organic residues became highly porous and more rigid and formed amorphous nanospherules. These nanospherules are morphologically similar to organic nanoglobules observed in the least-altered chondrites, chondritic porous interplanetary dust particles, and cometary samples, suggesting that irradiation of refractory organics could be a possible formation pathway for such nanoglobules. The storage modulus (elasticity) of photo-irradiated organic residues is ∼100 MPa irrespective of vibrational frequency, a value that is lower than the storage moduli of minerals and ice. Dust grains coated with such irradiated organics would therefore stick together efficiently, but growth to larger grains might be suppressed due to an increase in aggregate brittleness caused by the strong connections between grains.
Multipolar young planetary nebulae modelled as a precessing and orbiting jet with time-dependent ejection velocity

We have carried out 3D hydrodynamic simulations of precessing, variable ejection velocity bipolar jets in order to model multipolar protoplanetary (or planetary) nebulae. For these nebulae, we assume a binary source, with an asymptotic giant branch primary star which ejects an isotropic wind, and a companion which ejects the bipolar jet system. We find that it is possible to relate the large-scale morphological characteristics of these nebulae (lobe size, semi-aperture angle, number of observed lobes) to some of the parameters of the binary system, such as the ratio between the orbital and precession periods, the ratio between the masses of the binary components and the major axis of the elliptical orbit. Our results show that synthetic nebulae with well-defined lobe morphologies (resembling many of the observed multipolar planetary nebulae) are obtained from our models.
Neutrinoless double beta decay and the baryon asymmetry of the Universe

We discuss the impact of the observation of neutrinoless double beta decay on the washout of lepton number in the early universe. Neutrinoless double beta decay can be triggered by a large number of mechanisms that can be encoded in terms of standard model effective operators which violate lepton number by two units. We calculate the contribution of such operators to the rate of neutrinoless double beta decay and correlate it with the washout of lepton number induced by the same operators in the early universe. We find that the observation of a nonstandard contribution to neutrinoless double beta decay, i.e., not induced by the standard mass mechanism of light neutrino exchange, would correspond to an efficient washout of lepton number above the electroweak scale for many operators up to mass dimension 11. Combined with standard model sphaleron transitions, this would render many baryogenesis mechanisms at higher scales ineffective.
Also set-valued functions do not like iterative roots

In [1] Babbage studied (1.1) for f being the identity mapping. After him a lot of results concerning the general case of (1.1) in various settings have been proved. Many of them can be found in the monographs [12] and [13] by M. Kuczma and M. Kuczma, B. Choczewski, R. Ger, respectively, as well as in the book [19] by Gy. Targonski. Some recent results have been presented in the survey papers [3] and [2].
On Nulling, Drifting, and Their Interactions in PSRs J1741–0840 and J1840–0840

We report detailed investigation of nulling and drifting behavior of two pulsars PSRs J1741−0840 and J1840−0840 observed from the Giant Meterwave Radio Telescope at 625 MHz. PSR J1741−0840 was found to show a nulling fraction (NF) of around 30% ± 5% while PSR J1840−0840 was shown to have an NF of around 50% ± 6%. We measured drifting behavior from different profile components in PSR J1840−0840 for the first time with the leading component showing drifting with 13.5 ± 0.7 periods while the weak trailing component showed drifting of around 18 ± 1 periods. Large nulling hampers accuracy of these quantities derived using standard Fourier techniques. A more accurate comparison was drawn from driftband slopes, measured after sub-pulse modeling. These measurements revealed interesting sporadic and irregular drifting behavior in both pulsars. We conclude that the previously reported different drifting periodicities in the trailing component of PSR J1741−0840 is likely due to the spread in these driftband slopes. We also find that both components of PSR J1840−0840 show similar driftband slopes within the uncertainties. Unique nulling–drifting interaction is identified in PSR J1840−0840 where, on most occasions, the pulsar tends to start nulling after what appears to be the end of a driftband. Similarly, when the pulsar switches back to an emission phase, on most occasions it starts at the beginning of a new driftband in both components. Such behaviors have not been detected in any other pulsars to our knowledge. We also found that PSR J1741−0840 seems to have no memory of its previous burst phase while PSR J1840−0840 clearly exhibits memory of its previous state even after longer nulls for both components. We discuss possible explanations for these intriguing nulling–drifting interactions seen in both pulsars based on various pulsar nulling models.
The effect of clay on the mechanical properties of epoxy resins subjected to hygrothermal ageing

Epoxy polymers are an important class of material for use in various applications. Due to their hydrophilic nature, epoxy resins tend to absorb moisture. Absorption of moisture degrades the functional, structural and mechanical properties. For polymers, it is known that moisture absorption can lead to both reversible and irreversible changes. In this study, the combined effect of moisture and elevated temperature on the mechanical properties of Epon 862 and its nanocomposites were investigated. The extent of permanent damage on fracture toughness and flexural properties of epoxy, due to the aggressive degradation provided by hygrothermal ageing, was determined by drying the epoxy and their clay/epoxy nanocomposites after moisture absorption. From the investigation it was found that, hygrothermal ageing has detrimental effect on mechanical properties of both neat polymer and clay/polymer nanocomposite. Significant permanent damage was observed for fracture toughness and modulus, while the extent of permanent damage was less significant for flexural strength.
NuSTAR + XMM-Newton monitoring of the neutron star transient AX J1745.6-2901

AX J1745.6-2901 is a high-inclination (eclipsing) transient neutron star (NS) low-mass X-ray binary showcasing intense ionized Fe K absorption. We present here the analysis of 11 XMM-Newton and 15 NuSTAR new data sets (obtained between 2013 and 2016), therefore tripling the number of observations of AX J1745.6-2901 in outburst. Thanks to simultaneous XMM-Newton and NuSTAR spectra, we greatly improve on the fitting of the X-ray continuum. During the soft state, the emission can be described by a disc blackbody (kT ∼ 1.1–1.2 keV and inner disc radius rDBB ∼ 14 km), plus hot (kT ∼ 2.2–3.0 keV) blackbody radiation with a small emitting radius (rBB ∼ 0.5 − 0.8 km) likely associated with the boundary layer or NS surface, plus a faint Comptonization component. Imprinted on the spectra are clear absorption features created by both neutral and ionized matter. Additionally, positive residuals suggestive of an emission Fe K α disc line and consistent with relativistic ionized reflection are present during the soft state, while such residuals are not significant during the hard state. The hard-state spectra are characterized by a hard (Γ ∼ 1.9–2.1) power law, showing no evidence for a high energy cut-off (kTe > 60–140 keV) and implying a small optical depth (τ < 1.6). The new observations confirm the previously witnessed trend of exhibiting strong Fe K absorption in the soft state that significantly weakens during the hard state. Optical (GROND) and radio (GMRT) observations suggest for AX J1745.6-2901 a standard broad-band spectral energy distribution as typically observed in accreting NSs.
Observation of dynamical phase transitions in a topological nanomechanical system

Here, the authors present a novel scheme to study dynamical phase transitions (DPTs) from topological edge states in the Su-Schrieffer-Heeger model. They utilize eight coupled nanomechanical oscillators to simulate the quantum quenches and observe DPTs via directly measuring the Pancharatnam geometric phase in the experiment. The robustness of the DPT and its relation to equilibrium phases are explored. This nanomechanical lattice with its multiple modes, high quality factor, and temporal configurability offers unique advantages for research into nonequilibrium phenomena via an artificial solid-state platform.
CH3OH and H2O masers in high-mass star-forming regions

We present a comparison of Class ii CH3OH (6.7 GHz) and H2O (22.2 GHz) masers at high spatial resolution in a sample of 29 massive star-forming regions. Absolute positions of both maser types are compared with mm dust continuum, cm continuum and mid-infrared sources. All maser features - regardless of the species - are associated with massive mm cores, but only 3 out of 18 CH3OH masers and 6 out of 22 H2O masers are associated with cm emission likely indicating the presence of a recently ignited massive star. These observations of a homogenous sample of massive, young star-forming regions confirm earlier results, obtained for each maser species separately, that both maser types are signposts of high-mass star formation in very early evolutionary stages. The data are consistent with models that explain CH3OH maser emission by radiative pumping in moderately hot cores, requiring the absence, or only weak, free-free cm continuum radiation due to recently ignited stars. Mid-infrared sources are associated with both maser types in approximately 60% of the observed fields. Thus, mid-infrared objects may power maser sites, but the detection of strong mid-infrared emission is not strictly necessary because it might be heavily extincted. A comparison of the spatial separations between the dierent observed quantities and other properties of the star-forming regions does not reveal any correlation. Our data suggest that CH3OH and H2O masers need a similar environment (dense and warm molecular gas), but that, due to the dierent excitation processes (radiative pumping for CH3OH and collisional pumping for H2O), no spatial correlations exist. Spatial associations are probably coincidences due to insucient angular resolution and projection eects. The kinematic structures we find in the dierent maser species show no recognizable pattern, and we cannot draw firm conclusions as to whether the features are produced in disks, outflows or expanding shock waves.
High-Resolution Infrared Spectra of Bulge Globular Clusters: Liller 1 and NGC 6553

Using the NIRSPEC spectrograph at Keck II, we have obtained echelle spectra covering the range 1.5–1.8 μm for two of the brightest giants in Liller 1 and NGC 6553, old metal-rich globular clusters in the Galactic bulge. We use spectrum synthesis for the abundance analysis and find [Fe/H] = -0.3 ± 0.2 and [O/H] = 0.3 ± 0.1 (from the OH lines) for the giants in both clusters. We measure strong lines for the α-elements Mg, Ca, and Si, but the lower sensitivity of these lines to abundance permits us only to state a general [α/Fe] = 0.3 ± 0.2 dex. The composition of the clusters is similar to that of field stars in the bulge and is consistent with a scenario in which the clusters formed early, with rapid enrichment. We have difficulty achieving a good fit to the spectrum of NGC 6553 using either the low or the high values recently reported in the literature, unless unusually large or no α-element enhancements are adopted, respectively.
Galaxy and Mass Assembly: the evolution of the cosmic spectral energy distribution from z = 1 to z = 0

We present the evolution of the cosmic spectral energy distribution (CSED) from z = 1 to 0. Our CSEDs originate from stacking individual spectral energy distribution (SED) fits based on panchromatic photometry from the Galaxy And Mass Assembly (GAMA) and COSMOS data sets in 10 redshift intervals with completeness corrections applied. Below z = 0.45, we have credible SED fits from 100 nm to 1 mm. Due to the relatively low sensitivity of the far- infrared data, our far- infrared CSEDs contain a mix of predicted and measured fluxes above z = 0.45. Our results include appropriate errors to highlight the impact of these corrections. We show that the bolometric energy output of the Universe has declined by a factor of roughly 4 from 5.1 +/- 1.0 at z similar to 1 to 1.3 +/- 0.3 x 10(35) h(70) W Mpc(-3) at the current epoch. We show that this decrease is robust to cosmic sample variance, the SED modelling and other various types of error. Our CSEDs are also consistent with an increase in the mean age of stellar populations. We also show that dust attenuation has decreased over the same period, with the photon escape fraction at 150 nm increasing from 16 +/- 3 at z similar to 1 to 24 +/- 5 per cent at the current epoch, equivalent to a decrease in AFUV of 0.4 mag. Our CSEDs account for 68 +/- 12 and 61 +/- 13 per cent of the cosmic optical and infrared backgrounds, respectively, as defined from integrated galaxy counts and are consistent with previous estimates of the cosmic infrared background with redshift.
First Weak-lensing Results from “See Change”: Quantifying Dark Matter in the Two z ≳ 1.5 High-redshift Galaxy Clusters SPT-CL J2040–4451 and IDCS J1426+3508

We present a weak-lensing study of SPT-CL J2040–4451 and IDCS J1426+3508 at z = 1.48 and 1.75, respectively. The two clusters were observed in our “See Change” program, a Hubble Space Telescope survey of 12 massive high-redshift clusters aimed at high-z supernova measurements and weak-lensing estimation of accurate cluster masses. We detect weak but significant galaxy shape distortions using infrared images from the Wide Field Camera 3 (WFC3), which has not yet been used for weak-lensing studies. Both clusters appear to possess relaxed morphology in projected mass distribution, and their mass centroids agree nicely with those defined by both the galaxy luminosity and X-ray emission. Using a Navarro–Frenk–White profile, for which we assume that the mass is tightly correlated with the concentration parameter, we determine the masses of SPT-CL J2040–4451 and IDCS J1426 + 3508 to be and , respectively. The weak-lensing mass of SPT-CL J2040–4451 shows that the cluster is clearly a rare object. Adopting the central value, the expected abundance of such a massive cluster at is only in the parent 2500 sq. deg. survey. However, it is yet premature to claim that the presence of this cluster creates a serious tension with the current ΛCDM paradigm unless that tension will remain in future studies after marginalizing over many sources of uncertainties such as the accuracy of the mass function and the mass–concentration relation at the high-mass end. The mass of IDCS J1426+3508 is in excellent agreement with our previous Advanced Camera for Surveys-based weak-lensing result, while the much higher source density from our WFC3 imaging data makes the current statistical uncertainty % smaller.
The Signature of 44Ti in Cassiopeia A Revealed by IBIS/ISGRI on INTEGRAL

We report the detection of both the 67.9 and 78.4 keV 44Sc γ-ray lines in Cassiopeia A with the INTEGRAL IBIS/ISGRI instrument. Besides the robustness provided by spectroimaging observations, the main improvements compared to previous measurements are a clear separation of the two 44Sc lines together with an improved significance of the detection of the hard X-ray continuum up to 100 keV. These allow us to refine the determination of the 44Ti yield and to constrain the nature of the nonthermal continuum emission. By combining COMPTEL, BeppoSAX PDS and ISGRI measurements, we find a line flux of (2.5 ± 0.3) × 10-5 cm-2 s-1 leading to a synthesized 44Ti mass of 1.6 × 10-4 M☉. This high value suggests that Cas A is peculiar in comparison to other young supernova remnants, from which so far no line emission from 44Ti decay has been unambiguously detected.
Viable inflation in scalar-Gauss-Bonnet gravity and reconstruction from observational indices

In this paper the focus is on inflationary dynamics in the context of Einstein Gauss-Bonnet gravitational theories. We investigate the implications of the slow-roll condition on the slow-roll indices and we investigate how the inflationary dynamical evolution is affected by the presence of the Gauss-Bonnet coupling to the scalar field. For exemplification of our analysis we investigate how the dynamics of inflationary cubic, quartic order and also exponential scalar potentials are affected by the non-trivial Gauss-Bonnet coupling to the scalar field. As we demonstrate it is possible to obtain a viable phenomenology compatible with the observational data, although the canonical scalar field theory with cubic and quartic order potentials does not yield phenomenologically acceptable results. In addition, with regard to the exponential potential example, the Einstein Gauss-Bonnet extension of the single canonical scalar field model has an inherent mechanism that can trigger the graceful exit from inflation. Furthermore we introduce a bottom-up reconstruction technique, in the context of which by fixing the tensor-to-scalar ratio and the Hubble rate as a function of the $e$-foldings number, one is capable of reproducing the Einstein Gauss-Bonnet theory which generates the aforementioned quantities. We illustrate how the method works by using some relatively simple examples.
Dark matter and visible baryons in M33

In this paper we present new measurements of the gas kinematics in M33 using the CO J = 1 - 0 line. The resulting rotational velocities complement previous 21-cm line data for a very accurate and extended rotation curve of this nearby galaxy. The implied dark matter mass, within the total gaseous extent, is a factor of 5 higher than the visible baryonic mass. Dark matter density profiles with an inner cusp as steep as R - 1 , suggested by some numerical simulation of structures formation, are compatible with the actual data. The dark matter concentrations required for fitting the M33 rotation curve are very low but still marginally consistent with haloes forming in a standard cold dark matter cosmology. The M33 virialized dark halo is at least 50 times more massive than the visible baryons and its size is comparable with the M33-M31 separation. Inner cusps as steep as R - 1 . 5 are ruled out, while halo models with a large size core of constant density are consistent with the M33 data. A central excess of stars is needed and we evaluate its dynamical mass range. Using accurate rotational velocity gradients and the azimuthally averaged baryonic surface densities, we show that a disc instability can regulate the star formation activity in M33. Considering the gaseous surface density alone, the predicted outer star formation threshold radius is consistent with the observed drop of the Ha surface brightness if a shear rate criterion is used with the lowest possible value of velocity dispersion. The classical Toomre criterion predicts the size of the unstable region correctly only when the stellar or dark halo gravity, derived in this paper, is added to that of the gaseous disc.