Miracle-dz/UniFAR-FTUs huggingface dataset:
Radial-velocity measurements of subdwarf B stars

Subdwarf B (sdB) stars are hot, subluminous stars which are thought to be core-helium burning with thin hydrogen envelopes. The mechanism by which these stars lose their envelopes has been controversial, but it has been argued that binary star interaction is the main cause. Over the past decade we have conducted a radial-velocity study of a large sample of sdB stars, and have shown that a significant fraction of the field sdB population exists in binary systems. In 2002 and 2003, we published 23 new binary sdB stars and the definitions of their orbits. Here, we present the continuation of this project. We give the binary parameters for 28 systems, 18 of which are new. We also present our radial-velocity measurements of a further 108 sdBs. Of these, 88 show no significant evidence of orbital motion. The remaining 20 do show radial-velocity variations, and so are good candidates for further study. Based on these results, our best estimate for the binary fraction in the sdB population is 46-56 per cent. This is a lower bound since the radial-velocity variations of very long period systems would be difficult to detect over the baseline of our programme, and for some sources we have only a small number of measurements.
Minimizers and Gradient Flows of Attraction-Repulsion Functionals with Power Kernels and Their Total Variation Regularization

We study properties of an attractive-repulsive energy functional based on power-kernels, which can be used for halftoning of images. In the first part of this work, using a variational framework for probability measures, we examine existence and behavior of minimizers to the functional and to a regularization of it by a total variation term. Moreover, we introduce particle approximations to the functional and to its regularized version and prove their consistency in terms of Γ-convergence, which we additionally illustrate by numerical examples. In the second part, we consider the gradient flow of the functional in the 2-Wasserstein space and prove statements about its asymptotic behavior for large times, for which we employ the pseudo-inverse technique for probability measures in 1D. Depending on the parameter range, this includes existence of a subsequence converging to a steady state or even convergence of the whole trajectory to a limit which we can specify explicitly. For both parts of the work, a key ingredient is the generalized Fourier transform, which allows us to verify the conditional positive definiteness of the interaction kernel for coinciding attractive and repulsive exponents.
Photoproduction through Chern-Simons Term Induced Interactions in Holographic QCD

We employ both top-down and bottom-up holographic dual models of QCD to calculate vertex functions and couplings that are induced by the five-dimensional Chern-Simons term. We use these couplings to study the photoproduction of f{sub 1} mesons. The Chern-Simons-term-induced interaction leads to a simple relation between the polarization of the incoming photon and the final state f{sub 1} meson which should allow a clear separation of this interaction from competing processes.
Gravitational-thermodynamic instabilities of isothermal spheres in dS and AdS

Thermodynamical stability of fluid spheres is studied in the presence of a cosmological constant, both in the Newtonian limit, as well as in General Relativity. In all cases, an increase of the cosmological constant tends to stabilize the system, making asymptotically de Sitter space more thermodynamically stable than anti-de Sitter at the purely classical level. In addition, in the Newtonian case reentrant phase transitions are observed for a positive cosmological constant, due to its repelling property in this case. In General Relativity is studied the case of radiation, for which is found that the critical radius, at which an instability sets in, is always bigger than the black hole radius of the system and furthermore, at some value of the cosmological constant this critical radius hits at the cosmological horizon.
FISSURE IDENTIFICATION METHODS IN RICE SEEDS AFTER ARTIFICIAL DRYING

New, efficient, low-cost techniques for image processing and alternative machine learning for seed processing are of academic and industrial interest. This study aims to identify fissures in bark and peeled rice seeds using X-ray and RGB image processing techniques and machine learning. Samples of three batches of rice seeds were used: a batch of seeds not subjected to drying (peeled seed), and the other two comprised of dried seeds, one containing seeds with husk and another containing huskless seeds; each sample comprised 100 seeds. Images in X-ray and RGB formats were provided in the sequence processed in ImageJ software and introduced in the machine learning software, where they were pre-processed using the appropriate filters and then classified by
The Secular and Rotational Brightness Variations of Neptune

Neptune has brightened by more than 10% during the past several decades. We report on the analysis of published Johnson-Cousins B and V magnitudes dating back to 1954 along with new U, B, V, R, Rc, I and Ic photometry that we recorded during the past 24 years. Characteristic magnitudes, colors and albedos in all seven band-passes are derived from the ensemble of data. Additionally, 25 spectra spanning 26 hours of observation on 5 nights are analyzed. The spectrophotometry demonstrates that planetary flux and albedo is inversely related to the equivalent widths of methane bands. We attribute the changes in band strength, flux and albedo to the high altitude clouds which rotate across the planet's visible disk. Bright clouds increase albedo and flux while reducing methane absorption. Synthetic V magnitudes derived from the spectroscopy also agree closely with the photometric quantities, which cross-validates the two techniques. The spectroscopic and photometric results are discussed within the framework of the secular brightness variations of Neptune.
The 2d Gross-Neveu Model for Pseudovector Fermions and Tachyonic Mass Generation

Recent observations in the OPERA experiment suggest that the neutrino could propagate with speed that is superluminal. Based on early theoretical work on tachyonic fermions we shall study a modification of the Gross-Neveu model in two dimensions. We shall see that the theory results to the dynamical generation of real and imaginary masses. These imaginary masses indicate the possibility that tachyonic solutions (or instabilities) could exist in the theory. The implications of a tachyonic neutrino coming from astrophysical sources are critically discussed. Moreover, we present a toy model that consists of an U(2,2) invariant Dirac Lagrangian. This theory can have tachyonic masses as solutions. A natural mass splitting between the solutions is a natural outcome of the formalism.
Constructing mock catalogues for the REFLEX II galaxy cluster sample

We describe the construction of a suite of galaxy cluster mock catalogues from N-body simulations, based on the properties of the new ROSAT –ESO Flux Limited X-Ray (REFLEX II) galaxy cluster catalogue. Our procedure is based on the measurements of the cluster abundance, and involves the calibration of the underlying scaling relation linking the mass of dark matter haloes to the cluster X-ray luminosity determined in the ROSAT energy band 0.1–2.4 keV. In order to reproduce the observed abundance in the luminosity range probed by the REFLEX II X-ray luminosity function [0.01 < LX/(10 44 erg s −1 h −2 ) < 10], a mass–X-ray luminosity relation deviating from a simple power law is required. We discuss the dependence of the calibration of this scaling relation on the X-ray luminosity and the definition of halo masses and analyse the one- and two-point statistical properties of the mock catalogues. Our set of mock catalogues provides samples with self-calibrated scaling relations of galaxy clusters together with inherent properties of flux-limited surveys. This makes them a useful tool to explore different systematic effects and statistical methods involved in constraining both astrophysical and cosmological information from present and future galaxy cluster surveys.
Cytotoxicity and Genotoxicity of Senecio vulgaris L. Extracts: An In Vitro Assessment in HepG2 Liver Cells

Senecio vulgaris L. is a herbaceous species found worldwide. The demonstrated occurrence of pyrrolizidine alkaloids in this species and its ability to invade a great variety of habitats result in a serious risk of contamination of plant material batches addressed to the herbal teas market; this presents a potential health risk for consumers. In light of the above, this work aimed to assess the cytotoxic and genotoxic activity of S. vulgaris extracts in HepG2 cells. Dried plants were ground and extracted using two different methods, namely an organic solvent-based procedure (using methanol and chloroform), and an environmentally friendly extraction procedure (i.e., aqueous extraction), which mimicked the domestic preparation of herbal teas (5, 15, and 30 min of infusion). Extracts were then tested in HepG2 cells for their cytotoxic and genotoxic potentialities. Results were almost superimposable in both extracts, showing a slight loss in cell viability at the highest concentration tested, and a marked dose-dependent genotoxicity exerted by non-cytotoxic concentrations. It was found that the genotoxic effect is even more pronounced in aqueous extracts, which induced primary DNA damage after five minutes of infusion even at the lowest concentration tested. Given the broad intake of herbal infusions worldwide, this experimental approach might be proposed as a screening tool in the analysis of plant material lots addressed to the herbal infusion market.
THE MASSIVE YOUNG STAR-FORMING COMPLEX STUDY IN INFRARED AND X-RAY: MID-INFRARED OBSERVATIONS AND CATALOGS

Spitzer IRAC observations and stellar photometric catalogs are presented for the Massive Young Star-Forming Complex Study in the Infrared and X-ray (MYStIX). MYStIX is a multiwavelength census of young stellar members of 20 nearby (d < 4 kpc), Galactic, star-forming regions that contain at least one O star. All regions have data available from the Spitzer Space Telescope consisting of GLIMPSE or other published catalogs for 11 regions and results of our own photometric analysis of archival data for the remaining 9 regions. This paper seeks to construct deep and reliable catalogs of sources from the Spitzer images. Mid-infrared study of these regions faces challenges of crowding and high nebulosity. Our new catalogs typically contain fainter sources than existing Spitzer studies, which improves the match rate to Chandra X-ray sources that are likely to be young stars, but increases the possibility of spurious point-source detections, especially peaks in the nebulosity. IRAC color–color diagrams help distinguish spurious detections of nebular polycyclic aromatic hydrocarbon emission from the infrared excess associated with dusty disks around young stars. The distributions of sources on the mid-infrared color–magnitude and color–color diagrams reflect differences between MYStIX regions, including astrophysical effects such as stellar ages and disk evolution.
Double Spin Asymmetries of Inclusive Hadron Electroproduction From a Transversely Polarized He-3 Target

We report the measurement of beam-target double-spin asymmetries ALT in the inclusive production of identified hadrons, e +³He↑ → h + X, using a longitudinally polarized 5.9 GeV electron beam and a transversely polarized ³He target. Hadrons (π±, K± and proton) were detected at 16° with an average momentum h>=2.35 GeV/c and a transverse momentum (pT) coverage from 0.60 to 0.68 GeV/c. Asymmetries from the ³He target were observed to be non-zero for π± production when the target was polarized transversely in the horizontal plane. The π⁺ and π⁻ asymmetries have opposite signs, analogous to the behavior of ALT in semi-inclusive deep-inelastic scattering.
The Radial Acceleration Relation (RAR): Crucial Cases of Dwarf Disks and Low-surface-brightness Galaxies

McGaugh et al. have found, in a large sample of disk systems, a tight nonlinear relationship between the total radial accelerations g and their components gb that have arisen from the distribution of the baryonic matter. Here, we investigate the existence of such a relation in Dwarf Disk Spirals and Low Surface Brightness (LSB) galaxies on the basis of Karukes & Salucci and Di Paolo & Salucci. We have accurate mass profiles for 36 Dwarf Disk Spirals and 72 LSB galaxies. These galaxies have accelerations that cover the McGaugh range but also reach out to one order of magnitude below the smallest accelerations present in McGaugh et al. and span different Hubble Types. We found, in our samples, that the g versus gb relation has a very different profile and also other intrinsic novel properties, among those, the dependence on a second variable: the galactic radius, normalized to the optical radius Ropt, at which the two accelerations are measured. We show that the new far from trivial g versus relationship is a direct consequence of the complex coordinated mass distributions of the baryons and the dark matter (DM) in disk systems. Our analysis shows that the McGaugh et al. relation is a limiting case of a new universal relation that can be very well framed in the standard “DM halo in the Newtonian Gravity” paradigm.
Chandra and NuSTAR Follow-up Observations of Swift-BAT-selected AGNs

Based on current models of the cosmic X-ray background (CXB), heavily obscured active galactic nuclei (AGNs) are expected to make up ∼10% of the peak emission of the CXB and ∼20% of the total population of AGNs, yet few of these sources have been recorded and characterized in current surveys. Here we present the Chandra follow-up observation of 14 AGNs detected by Swift-BAT. For five sources in the sample, NuSTAR observations in the 3–80 keV band are also available. The X-ray spectral fitting over the 0.3–150 keV energy range allows us to determine the main X-ray spectral parameters, such as the photon index and the intrinsic absorption, of these objects and to make hypotheses on the physical structures responsible for the observed spectra. We find that 13 of the 14 objects are absorbed AGNs, and one is a candidate Compton-thick AGN, having intrinsic absorption cm−2. Finally, we verified that the use of NuSTAR observations is strategic to strongly constrain the properties of obscured AGNs, since the best-fit values we obtained for parameters such as the power-law photon index Γ and the intrinsic absorption changed sometimes significantly fitting the spectra with and without the use of NuSTAR data.
$CP$ phase from twisted Higgs vacuum expectation value in extra dimension

We propose a new mechanism for generating a CP phase via Higgs a vacuum expectation value originating from geometry of an extra dimension. A twisted boundary condition is the key to produce an extra-dimension coordinate-dependent vacuum expectation value, which contains a CP phase degree of freedom and can be a new source of a CP phase in higher-dimensional gauge theories. As an illustrative example, we apply our mechanism to a five-dimensional gauge theory with point interactions and show that our mechanism can dynamically produce a nontrivial CP-violating phase with electroweak symmetry breaking, even though the five-dimensional model does not include any CP-violating phases of Yukawa couplings in the five-dimensional Lagrangian because of a single generation of five-dimensional fermions. We apply our mechanism to a model with point interactions, which has no source of CP-violating phases in the couplings of the higher-dimensional action, and show that a nontrivial CP phase dynamically appears.
The emergent Copenhagen interpretation of quantum mechanics

We introduce a new and conceptually simple interpretation of quantum mechanics based on reduced density matrices of sub-systems from which the standard Copenhagen interpretation emerges as an effective description of macroscopically large systems. This interpretation describes a world in which definite measurement results are obtained with probabilities that reproduce the Born rule. Wave function collapse is seen to be a useful but fundamentally unnecessary piece of prudent book keeping which is only valid for macro-systems. The new interpretation lies in a class of modal interpretations in that it applies to quantum systems that interact with a much larger environment. However, we show that it does not suffer from the problems that have plagued similar modal interpretations like macroscopic superpositions and rapid flipping between macroscopically distinct states. We describe how the interpretation fits neatly together with fully quantum formulations of statistical mechanics and that a measurement process can be viewed as a process of ergodicity breaking analogous to a phase transition. The key feature of the new interpretation is that joint probabilities for the ergodic subsets of states of disjoint macro-systems only arise as emergent quantities. Finally we give an account of the EPR–Bohm thought experiment and show that the interpretation implies the violation of the Bell inequality characteristic of quantum mechanics but in a way that is rather novel. The final conclusion is that the Copenhagen interpretation gives a completely satisfactory phenomenology of macro-systems interacting with micro-systems.
ELECTRODYNAMICS ON EXTRASOLAR GIANT PLANETS

Strong ionization on close-in extrasolar giant planets (EGPs) suggests that their atmospheres may be affected by ion drag and resistive heating arising from wind-driven electrodynamics. Recent models of ion drag on these planets, however, are based on thermal ionization only and do not include the upper atmosphere above the 1 mbar level. These models are also based on simplified equations of resistive magnetohydrodynamics that are not always valid in extrasolar planet atmospheres. We show that photoionization dominates over thermal ionization over much of the dayside atmosphere above the 100 mbar level, creating an upper ionosphere dominated by ionization of H and He and a lower ionosphere dominated by ionization of metals such as Na, K, and Mg. The resulting dayside electron densities on close-in exoplanets are higher than those encountered in any planetary ionosphere of the solar system, and the conductivities are comparable to the chromosphere of the Sun. Based on these results and assumed magnetic fields, we constrain the conductivity regimes on close-in EGPs and use a generalized Ohm's law to study the basic effects of electrodynamics in their atmospheres. We find that ion drag is important above the 10 mbar level where it can also significantly alter the energy balance through resistive heating. Due to frequent collisions of the electrons and ions with the neutral atmosphere, however, ion drag is largely negligible in the lower atmosphere below the 10 mbar level for a reasonable range of planetary magnetic moments. We find that the atmospheric conductivity decreases by several orders of magnitude in the night side of tidally locked planets, leading to a potentially interesting large-scale dichotomy in electrodynamics between the day and night sides. A combined approach that relies on UV observations of the upper atmosphere, phase curve and Doppler measurements of global dynamics, and visual transit observations to probe the alkali metals can potentially be used to constrain electrodynamics in the future.
RE-EVALUATING WASP-12b: STRONG EMISSION AT 2.315 μm, DEEPER OCCULTATIONS, AND AN ISOTHERMAL ATMOSPHERE

We revisit the atmospheric properties of the extremely hot Jupiter WASP-12b in light of several new developments. First, we present new narrowband (2.315 μm) secondary eclipse photometry, which exhibits a planet/star flux ratio of 0.45% ± 0.06%, corresponding to a brightness temperature of 3640 ± 230 K; second, recent Spitzer/Infrared Array Camera and Hubble Space Telescope/Wide Field Camera 3 observations; and third, a recently observed star only 1″ from WASP-12, which has diluted previous observations and which we further characterize here. We correct past WASP-12b eclipse measurements for the presence of this object, and we revisit the interpretation of WASP-12b's dilution-corrected emission spectrum. The resulting planetary emission spectrum is well approximated by a blackbody, and consequently our primary conclusion is that the planet's infrared photosphere is nearly isothermal. Thus, secondary eclipse spectroscopy is relatively ill suited to constrain WASP-12b's atmospheric abundances, and transmission spectroscopy may be necessary to achieve this goal.
Supernovae and radio transients in M82

We present optical and near-infrared (IR) photometry and near-IR spectroscopy of SN 2004am, the only optically detected supernova (SN) in M 82. These demonstrate that SN 2004am was a highly reddened type II-P SN similar to the low luminosity type II-P events such as SNe 1997D and 2005cs. We show that SN 2004am was located coincident with the obscured super star cluster M 82-L, and from the cluster age infer a progenitor mass of 12 +7/-3 Msun. In addition to this, we present a high spatial resolution Gemini-N K-band adaptive optics image of the site of SN 2008iz and a second transient of uncertain nature, both detected so far only at radio wavelengths. Using image subtraction techniques together with archival data from the Hubble Space Telescope, we are able to recover a near-IR transient source co-incident with both objects. We find the likely extinction towards SN 2008iz to be not more than Av ~ 10. The nature of the second transient remains elusive and we regard an extremely bright microquasar in M 82 as the most plausible scenario.
Herschel : the first science highlights Special feature L etter to the E ditor Small-scale structure in the Rosette molecular cloud revealed by Herschel ,

We present a preliminary analysis of the small-scale structure found in new 70−520 μm continuum maps of the Rosette molecular cloud (RMC), obtained with the SPIRE and PACS instruments of the Herschel Space Observatory. We find 473 clumps within the RMC using a new structure identification algorithm, with sizes up to ∼1.0 pc in diameter. A comparison with recent Spitzer maps reveals that 371 clumps are “starless” (without an associated young stellar object), while 102 are “protostellar. ” Using the respective values of dust temperature, we determine the clumps have masses (MC) over the range −0.75 ≤ log (MC/M ) ≤ 2.50. Linear fits to the high-mass tails of the resulting clump mass spectra (CMS) have slopes that are consistent with those found for high-mass clumps identified in CO emission by other groups.
Asymptotic pointwise behavior for systems of semilinear wave equations in three space dimensions

In connection with the weak null condition, Alinhac introduced a sufficient condition for global existence of small amplitude solutions to systems of semilinear wave equations in three space dimensions. We introduce a slightly weaker sufficient condition for the small data global existence, and we investigate the asymptotic pointwise behavior of global solutions for systems satisfying this condition. As an application, the asymptotic behavior of global solutions under the Alinhac condition is also derived.