Miracle-dz/UniFAR-FTUs huggingface dataset:
Systematic biases on galaxy haloes parameters from Yukawa‐like gravitational potentials

A viable alternative to the dark energy as a solution of the cosmic speed up problem is represented by Extended Theories of Gravity. Should this be indeed the case, there will be an impact not only on cosmological scales, but also at any scale, from the Solar System to extragalactic ones. In particular, the gravitational potential can be different from the Newtonian one commonly adopted when computing the circular velocity fitted to spiral galaxies rotation curves. Phenomenologically modelling the modified point mass potential as the sum of a Newtonian and a Yukawa-like correction, we simulate observed rotation curves for a spiral galaxy described as the sum of an exponential disc and a Navarro-Frenk-White (NFW) dark matter halo. We then fit these curves assuming parameterized halo models (either with an inner cusp or a core) and using the Newtonian potential to estimate the theoretical rotation curve. Such a study allows us to investigate the bias on the disc and halo model parameters induced by the systematic error induced by forcing the gravity theory to be Newtonian when it is not. As a general result, we find that both the halo scale length and virial mass are significantly overestimated, while the dark matter mass fraction within the disc optical radius is typically underestimated. Moreover, should the Yukawa scale length be smaller than the disc half mass radius, then the logarithmic slope of the halo density profile would turn out to be shallower than the NFW one. Finally, cored models are able to fit quite well the simulated rotation curves, provided the disc mass is biased high in agreement with the results in literature, favoring cored haloes and maximal discs. Such results make us argue that the cusp/core controversy could actually be the outcome of an incorrect assumption about which theory of gravity must actually be used in computing the theoretical circular velocity.
Dynamical and Thermodynamical Aspects of Interacting Kerr Black Holes

We consider the asymptotically flat double-Kerr solution for two equal mass black holes with either the same or opposite angular momentum and with a massless strut between them. For fixed angular momentum and mass, the angular velocity of two corotating Kerr black holes decreases as they approach one another, from the Kerr value at infinite separation to the value of a single Kerr black hole with twice the mass and the angular momentum at the horizons merging limit. We show that the ratio J/M 2 for extremal corotating Kerr black holes varies from unity at infinite separation to two at the merging limit. These results are interpreted in terms of rotational dragging and compared with the case of counterrotating Kerr black holes. We then analyze the merging of ergoregions. In the corotating case the merger point occurs at an angle of π/2, in agreement with recent general arguments. In the counterrotating case the ergoregions never merge. We study the horizon geometry for both cases as a function of the distance and provide embedding diagrams. Finally, we study the thermodynamical evolution of the corotating double-Kerr system, showing that, in the canonical ensemble, it is thermodynamically stable for fast spinning black holes. As for single Kerr black holes the stable and unstable phases are separated by a second order phase transition. We show that for large fixed angular momentum two Kerr black holes reach a minimum distance, before horizon merging has occurred, where the thermodynamical approximation breaks down. We also consider the microcanonical ensemble to study the maximal energy that can be extracted from the double-Kerr system as a function of the separation between the black holes.
Forming disk galaxies in major mergers - II. The central mass concentration problem and a comparison of GADGET3 with GIZMO

Context. In a series of papers, we study the major merger of two disk galaxies in order to establish whether or not such a merger can produce a disk galaxy. Aims. Our aim here is to describe in detail the technical aspects of our numerical experiments. Methods. We discuss the initial conditions of our major merger, which consist of two protogalaxies on a collision orbit. We show that such merger simulations can produce a non-realistic central mass concentration, and we propose simple, parametric, active galactic nuclei (AGN)-like feedback as a solution to this problem. Our AGN-like feedback algorithm is very simple: at each time-step we take all particles whose local volume density is above a given threshold value and increase their temperature to a preset value. We also compare the GADGET3 and GIZMO codes, by applying both of them to the same initial conditions. Results. We show that the evolution of isolated protogalaxies resembles the evolution of disk galaxies, thus arguing that our protogalaxies are well suited for our merger simulations. We demonstrate that the problem with the unphysical central mass concentration in our merger simulations is further aggravated when we increase the resolution. We show that our AGN-like feedback removes this non-physical central mass concentration, and thus allows the formation of realistic bars. Note that our AGN-like feedback mainly affects the central region of a model, without significantly modifying the rest of the galaxy. We demonstrate that, in the context of our kind of simulation, GADGET3 gives results which are very similar to those obtained with the PSPH (density independent SPH) flavor of GIZMO. Moreover, in the examples we tried, the differences between the results of the two flavors of GIZMO – namely PSPH, and MFM (mesh-less algorithm) – are similar to and, in some comparisons, larger than the differences between the results of GADGET3 and PSPH.
Understanding the performance of the low energy neutrino factory: the dependence on baseline distance and stored-muon energy

Motivated by recent hints of large {\theta}13 from the T2K, MINOS and Double Chooz experiments, we study the physics reach of a Low Energy Neutrino Factory (LENF) and its dependence on the chosen baseline distance, L, and stored-muon energy, E_{\mu}, in order to ascertain the configuration of the optimal LENF. In particular, we study the performance of the LENF over a range of baseline distances from 1000 km to 4000 km and stored-muon energies from 4 GeV to 25 GeV, connecting the early studies of the LENF (1300 km, 4.5 GeV) to those of the conventional, high-energy neutrino factory design (4000 km and 7000 km, 25 GeV). Three different magnetized detector options are considered: a Totally-Active Scintillator Detector (TASD) and two models of a liquid-argon detector distinguished by optimistic and conservative performance estimates. In order to compare the sensitivity of each set-up, we compute the full {\delta}-dependent discovery contours for the determination of non-zero {\theta}13, CP-violating values of {\delta} and the mass hierarchy. In the case of large {\theta}13 with sin^2(2*{\theta}13) = (few)*10^{-3}, the LENF provides a strong discovery potential over the majority of the L-E_{\mu} parameter space and is a promising candidate for the future generation of long baseline experiments aimed at discovering CP-violation and the mass hierarchy, and at making a precise determination of the oscillation parameters.
Fracture Resistance of Provisional Crowns Fabricated by Conventional, CAD/CAM, and 3D Printing Techniques

Purpose: The aim of this study was to compare fracture resistance of provisional restorations fabricated with conventional manual procedure, CAD/CAM milling and 3D Printing techniques. Materials and Methods : one human upper first premolar was prepared and duplicated using epoxy resin to produce twenty one dies. Accordingly, a total of (N=21) provisional crowns were constructed. The Constructed provisional restorations were divided into 3 groups according to the method of construction (n=7 for each group), Group 1: Provisional crowns were constructed using conventional manual technique, Group2: Provisional crowns were constructed using CAD/CAM milling technique, Group3: Provisional crowns were constructed using 3D Printing technique. All Provisional crowns were bonded to their corresponding epoxy resin dies by using CharmTemp ZONE temporary cement and subjected to thermocycling procedure simulating approximately one month of clinical situations Results: Statistical analysis showed that the fracture resistance of CAD/CAM samples (group 2), recorded the statistically significant highest mean fracture resistance value (910.20 ± 118.95), followed by 3D Printing samples (group 3) (720.80 ± 129.57), while the lowest value was recorded for Conventional samples (group 1) (626.71 ± 103.23). ANOVA test showed that there was no significant difference between 3D Printing samples (group 3) and Conventional samples (group 1). Conclusion: CAD/CAM provisional crowns have superior strength than 3D Printing and conventional crowns.
RAPID TeV VARIABILITY IN BLAZARS AS A RESULT OF JET–STAR INTERACTION

We propose a new model for the description of ultra-short flares from TeV blazars by compact magnetized condensations (blobs), produced when red giant stars cross the jet close to the central black hole. Our study includes a simple dynamic model for the evolution of the envelope lost by the star in the jet and its high-energy nonthermal emission through different leptonic and hadronic radiation mechanisms. We show that the fragmented envelope of the star can be accelerated to Lorentz factors up to 100 and effectively radiate the available energy in gamma rays predominantly through proton synchrotron radiation or external inverse Compton scattering of electrons. The model can readily explain the minute-scale TeV flares on top of longer (typical timescales of days) gamma-ray variability as observed from the blazar PKS 2155−304. In the framework of the proposed scenario, the key parameters of the source are robustly constrained. In the case of proton synchrotron origin of the emission, a mass of the central black hole of MBH ≈ 108 M☉, a total jet power of Lj ≈ 2 × 1047 erg s−1, and a Doppler factor of the gamma-ray emitting blobs of δ ⩾ 40 are required. For the external inverse Compton model, parameters of MBH ≈ 108 M☉, Lj ≈ 1046 erg s−1, and δ ⩾ 150 are required.
CHARACTERIZATION OF SLOAN DIGITAL SKY SURVEY STELLAR PHOTOMETRY

We study the photometric properties of stars in the data archive of the Sloan Digital Sky Survey (SDSS), the prime aim being to understand the photometric calibration over the entire data set. It is confirmed that the photometric calibration of point sources is accurately on the system defined by the SDSS standard stars. We have also confirmed that the photometric synthesis of the SDSS spectrophotometric data gives broadband fluxes that agree with the photometry with errors of no more than 0.04 mag and little systematic tilt with wavelength. This verifies that the response functions of the 2.5 m telescope system are well characterized. We locate stars in the SDSS photometric system, so that stars can roughly be classified into spectral classes from the color information. We show how metallicity and surface gravity affect colors, and that stars contained in the SDSS general catalog, plotted in color space, show a distribution that matches well with what is anticipated from the variations of metallicity and surface gravity. The color–color plots are perfectly consistent among the three samples—stars in the SDSS general catalog, SDSS standard stars, and spectrophotometric stars of Gunn & Stryker—especially when some considerations are taken into account of the differences (primarily metallicity) of the samples. We show that the g − r-inverse temperature relation is tight and can be used as a good estimator of the effective temperature of stars over a fairly wide range of effective temperatures. We also confirm that the colors of G2V stars in the SDSS photometric system match well with the Sun.
Microbiological Changes in Chicken Burger Formulated With Some Spices and Herbs During Frozen Storage.

: This study was conducted to test the effect of microbial inhibitor of spices and herbs commonly added to the foods. Spices and herbs were used in this study namely: thyme, rosemary, sage, marjoram and black seeds to study the effect of these spices on the growth of aerobic plate counts, psychrotrophic bacteria, proteolytic bacteria, lipolytic bacteria, yeasts and molds as well as one type of bacteria caus-ing food poisoning, ( Staphylococcus aureus ) as well as coliform group in order to preserve and improve the microbial quality of chicken burger. Two con-centrations of these spices (0.5 and 1%) were employed in chicken burger stored at -18˚C for 6 months. Study indicated that the number of microorganisms decreased with increasing duration of frozen storage in all treated samples compared to that of control. The study revealed that the addition of spices and herbs at level 1% led to reduce the number of microorganisms as much more than the addition at 0.5%. Likewise, the results showed that thyme was the most effective herb on reduction of microorganism followed by sage, rosemary and then marjoram, while black seeds gave less inhibitory effect. Generally, as microbiologically the end of storage period recording less than 10 5 cell/gm.
A New Galactic Extinction Map in High Ecliptic Latitudes

In this study, we derived a galactic extinction map in high ecliptic latitudes for |\beta| > 30 degrees. The dust temperature distribution was derived from the intensities at 100 and 140 \mu m with a spatial resolution of 5'. The intensity at 140 \mu m was derived from the intensities at 60 and 100 \mu m of the IRAS data assuming two tight correlations between the intensities at 60, 100, and 140 \mu m of the COBE/DIRBE data. We found that these correlations can be separated into two correlations by the antenna temperature of the radio continuum at 41 GHz. Because the present study can trace the 5'-scale spatial variation in the dust temperature distribution, it has an advantage over the extinction map derived by Schlegel, Finkbeiner, and Davis, who used the DIRBE maps to derive dust temperature distribution with a spatial resolution of 1 degrees. We estimated the accuracy of our method by comparing it with that of Schlegel, Finkbeiner, and Davis. The spatial resolution difference was found to be significant. The area in which the significant difference is confirmed occupies 28% of the region for |\beta| > 30 degrees. With respect to the estimation of extragalactic reddening, the present study has an advantage over the extinction map derived by Dobashi (2011), which was based on the 2MASS Point Source Catalog, because our extinction map is derived on the basis of far-infrared emission. Dobashi's extinction map exhibits a maximum value that is lower than that of our map in the galactic plane and a signal-to-noise ratio that is lower than that of our map in high galactic latitudes. This significant difference is confirmed in 81% of the region for |\beta| > 30 degrees. In the areas where the significant differences are confirmed, the extinction should be estimated using our method rather than the previous methods.
Jacobi mapping approach for a precise cosmological weak lensing formalism

Cosmological weak lensing has been a highly successful and rapidly developing research field since the first detection of cosmic shear in 2000. However, it has recently been pointed out in Yoo et al. that the standard weak lensing formalism yields gauge-dependent results and, hence, does not meet the level of accuracy demanded by the next generation of weak lensing surveys. Here, we show that the Jacobi mapping formalism provides a solid alternative to the standard formalism, as it accurately describes all the relativistic effects contributing to the weak lensing observables. We calculate gauge-invariant expressions for the distortion in the luminosity distance, the cosmic shear components and the lensing rotation to linear order including scalar, vector and tensor perturbations. In particular, the Jacobi mapping formalism proves that the rotation is fully vanishing to linear order. Furthermore, the cosmic shear components contain an additional term in tensor modes which is absent in the results obtained with the standard formalism. Our work provides further support and confirmation of the gauge-invariant lensing formalism needed in the era of precision cosmology.
Creation and counting of defects in a temperature quenched Bose-Einstein Condensate

We study the spontaneous formation of defects in the order parameter of a trapped ultracold bosonic gas while crossing the critical temperature for Bose-Einstein Condensation (BEC) at different rates. The system has the shape of an elongated ellipsoid, whose transverse width can be varied to explore dimensionality effects. For slow enough temperature quenches we find a power-law scaling of the average defect number with the quench rate, as predicted by the Kibble-Zurek mechanism. A breakdown of such a scaling is found for fast quenches, leading to a saturation of the average defect number. We suggest an explanation for this saturation in terms of the mutual interactions among defects.
Practical fast gate rate InGaAs/InP single-photon avalanche photodiodes

We present a practical and easy-to-implement method for high-speed near infrared single-photon detection based on InGaAs/InP single-photon avalanche photodiodes (SPADs), combining aspects of both sine gating and self-differencing techniques. At a gating frequency of 921 MHz and temperature of −30 °C we achieve a detection efficiency of 9.3%, a dark count probability of 2.8×10−6 ns−1, while the afterpulse probability is 1.6×10−4 ns−1, with a 10 ns “count-off time” setting. In principle, the maximum count rate of the SPAD can approach 100 MHz, which can significantly improve the performance for diverse applications.
Expanding CO Shells in the Orion A Molecular Cloud

We present the discovery of expanding spherical shells around low- to intermediate-mass young stars in the Orion A giant molecular cloud using observations of 12 CO (1–0) and 13 CO (1–0) from the Nobeyama Radio Observatory 45 m telescope. The shells have radii from 0.05 to 0.85 pc and expand outward at 0.8–5 km s−1. The total energy in the expanding shells is comparable to protostellar outflows in the region. Together, shells and outflows inject enough energy and momentum to maintain the cloud turbulence. The mass-loss rates required to power the observed shells are two to three orders of magnitude higher than predicted for line-driven stellar winds from intermediate-mass stars. This discrepancy may be resolved by invoking accretion-driven wind variability. We describe in detail several shells in this paper and present the full sample in the online journal.
Manifold spirals, disc–halo interactions, and the secular evolution inN-body models of barred galaxies

The manifold theory of barred-spiral structure provides a dynamical mechanism explaining how spiral arms beyond the ends of galactic bars can be supported by chaotic flows extending beyond the bar's co-rotation zone. We discuss its applicability to N-body simulations of secularly evolving barred galaxies. In these simulations, we observe consecutive `incidents' of spiral activity, leading to a time-varying disc morphology. Besides disc self-excitations, we provide evidence of a newly noted excitation mechanism related to the `off-centering' effect: particles ejected in elongated orbits at major incidents cause the disc center-of-mass to recoil and be set in a wobble-type orbit with respect to the halo center of mass. The time-dependent m=1 perturbation on the disc by the above mechanism correlates with the excitation of new incidents of non-axisymmetric activity beyond the bar. At every new excitation, the manifolds act as dynamical avenues attracting particles which are directed far from corotation along chaotic orbits. The fact that the manifolds evolve morphologically in time, due to varying non-axisymmetric perturbations, allows to reconcile manifolds with the presence of multiple patterns and frequencies in the disc. We find a time-oscillating pattern speed profile $\Omega_p(R)$ at distances R between the bar's corotation, at resonance with the succession of minima and maxima of the non-axisymmetric activity beyond the bar. Finally, we discuss disc thermalization, i.e., the evolution of the disc velocity dispersion profile and its connection with disc responsiveness to manifold spirals.
Binary neutron star merger rate via the luminosity function of short gamma-ray bursts

The luminosity function of short Gamma Ray Bursts (GRBs) is modelled by using the available catalogue data of all short GRBs (sGRBs) detected till October, 2017. The luminosities are estimated via the `pseudo-redshifts' obtained from the `Yonetoku correlation', assuming a standard delay distribution between the cosmic star formation rate and the production rate of their progenitors. While the simple powerlaw is ruled out to high confidence, the data is fit well both by exponential cutoff powerlaw and broken powerlaw models. Using the derived parameters of these models along with conservative values in the jet opening angles seen from afterglow observations, the true rate of short GRBs are derived. Assuming a short GRB is produced from each binary neutron star merger (BNSM), the rate of gravitational wave (GW) detections from these mergers are derived for the past, present and future configurations of the GW detector networks. Stringent lower limits of $1.87 \pyr$ for the aLIGO-VIRGO, and $3.11 \pyr$ for the upcoming aLIGO-VIRGO-KAGRA-LIGO/India configurations are thus derived for the BNSM rate at $68 \%$ confidence. The BNSM rates calculated from this work and that independently inferred from the observation of the only confirmed BNSM observed till date, are shown to have a mild tension; however the scenario that all BNSMs produce sGRBs cannot be ruled out.
FEEDBACK FROM HIGH-MASS X-RAY BINARIES ON THE HIGH-REDSHIFT INTERGALACTIC MEDIUM: MODEL SPECTRA

Massive stars at redshifts z ≳ 6 are predicted to have played a pivotal role in cosmological reionization as luminous sources of ultraviolet (UV) photons. However, the remnants of these massive stars could be equally important as X-ray-luminous (LX ∼ 1038 erg s−1) high-mass X-ray binaries (HMXBs). Because the absorption cross section of neutral hydrogen decreases sharply with photon energy (σ∝E−3), X-rays can escape more freely than UV photons from the star-forming regions in which they are produced, allowing HMXBs to make a potentially significant contribution to the ionizing X-ray background during reionization. In this paper, we explore the ionizing power of HMXBs at redshifts z ≳ 6 using a Monte Carlo model for a coeval stellar population of main-sequence stars and HMXBs. Using the archetypal Galactic HMXB Cygnus X-1 as our template, we propose a composite HMXB spectral energy distribution consisting of blackbody and power-law components, whose contributions depend on the accretion state of the system. We determine the time-dependent ionizing power of a combined population of UV-luminous stars and X-ray-luminous HMXBs and deduce fitting formulae for the boost in the population's ionizing power arising from HMXBs; these fits allow for simple implementation of HMXB feedback in numerical simulations. Based on this analysis, we estimate the contribution of high-redshift HMXBs to the present-day soft X-ray background, and we show that it is a factor of ∼100–1000 smaller than the observed limit. Finally, we discuss the implications of our results for the role of HMXBs in reionization and in high-redshift galaxy formation.