Miracle-dz/UniFAR-FTUs huggingface dataset:
Manifestation of geometric frustration on magnetic and thermodynamic properties of the pyrochlores Sm 2 X 2 O 7 (X=Ti,Zr)

We present here magnetization, specific heat, and Raman studies on single-crystalline specimens of the first pyrochlore member ${\mathrm{Sm}}_{2}{\mathrm{Ti}}_{2}{\mathrm{O}}_{7}$ of the rare-earth titanate series. Its analogous compound ${\mathrm{Sm}}_{2}{\mathrm{Zr}}_{2}{\mathrm{O}}_{7}$ in the rare-earth zirconate series is also investigated in the polycrystalline form. The Sm spins in ${\mathrm{Sm}}_{2}{\mathrm{Ti}}_{2}{\mathrm{O}}_{7}$ remain unordered down to at least $T=0.5\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. The absence of magnetic ordering is attributed to very small values of exchange $({\ensuremath{\theta}}_{\mathrm{cw}}\ensuremath{\sim}\ensuremath{-}0.26\phantom{\rule{0.3em}{0ex}}\mathrm{K})$ and dipolar interaction $({\ensuremath{\mu}}_{\mathrm{eff}}\ensuremath{\sim}0.15\phantom{\rule{0.3em}{0ex}}{\ensuremath{\mu}}_{B})$ between the ${\mathrm{Sm}}^{3+}$ spins in this pyrochlore. In contrast, the pyrochlore ${\mathrm{Sm}}_{2}{\mathrm{Zr}}_{2}{\mathrm{O}}_{7}$ is characterized by a relatively large value of Sm-Sm spin exchange $({\ensuremath{\theta}}_{\mathrm{cw}}\ensuremath{\sim}\ensuremath{-}10\phantom{\rule{0.3em}{0ex}}\mathrm{K})$; however, long-range ordering of the ${\mathrm{Sm}}^{3+}$ spins is not established at least down to $T=0.67\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ due to frustration of the ${\mathrm{Sm}}^{3+}$ spins on the pyrochlore lattice. The ground state of ${\mathrm{Sm}}^{3+}$ ions in both pyrochlores is a well-isolated Kramers doublet. The higher-lying crystal field excitations are observed in the low-frequency region of the Raman spectra of the two compounds recorded at $T=10\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. At higher temperatures, the magnetic susceptibility of ${\mathrm{Sm}}_{2}{\mathrm{Ti}}_{2}{\mathrm{O}}_{7}$ shows a broad maximum at $T=140\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, while that of ${\mathrm{Sm}}_{2}{\mathrm{Zr}}_{2}{\mathrm{O}}_{7}$ changes monotonically. Whereas ${\mathrm{Sm}}_{2}{\mathrm{Ti}}_{2}{\mathrm{O}}_{7}$ is a promising candidate for investigating spin fluctuations on a frustrated lattice, as indicated by our data, the properties of ${\mathrm{Sm}}_{2}{\mathrm{Zr}}_{2}{\mathrm{O}}_{7}$ seem to conform to a conventional scenario where geometrical frustration of the spin excludes their long-range ordering.
SDSS J143244.91+301435.3: a link between radio-loud narrow-line Seyfert 1 galaxies and compact steep-spectrum radio sources?

We present SDSSJ143244.91+301435.3, a new case of radio-loud narrow line Seyfert 1 (RL NLS1) with a relatively high radio power (P1.4GHz=2.1x10^25 W Hz^-1) and large radioloudness parameter (R1.4=600+/-100). The radio source is compact with a linear size below ~1.4 kpc but, contrary to most of the RL NLS1 discovered so far with such a high R1.4, its radio spectrum is very steep (alpha=0.93) and not supporting a 'blazar-like' nature. Both the small mass of the central super-massive black-hole and the high accretion rate relative to the Eddington limit estimated for this object (3.2x10^7 Msun and 0.27, respectively, with a formal error of ~0.4 dex on both quantities) are typical of the class of NLS1. Through a modeling of the spectral energy distribution of the source we have found that the galaxy hosting SDSSJ143244.91+301435.3 is undergoing a quite intense star-formation (SFR=50 Msun y^-1) which, however, is expected to contribute only marginally (~1 per cent) to the observed radio emission. The radio properties of SDSSJ143244.91+301435.3 are remarkably similar to those of compact steep spectrum (CSS) radio sources, a class of AGN mostly composed by young radio galaxies. This may suggest a direct link between these two classes of AGN, with the CSS sources possibly representing the misaligned version (the so-called parent population) of RL NLS1 showing blazar characteristics.
Deformation and cluster structures in 12 C studied with configuration mixing using Skyrme interactions

described. The second and third 0 + states, 0 + and 0 + , appear at around 8.8 MeV and 15 MeV, respectively. The 0 + state shows a structure consistent with former results of the �-cluster models, however, the calculated radius of the 0 + state is smaller than those calculations. The three-�linear-chain configuration dominates in the 0 + state.
THERMAL PLASMA IN THE GIANT LOBES OF THE RADIO GALAXY CENTAURUS A

We present a Faraday rotation measure (RM) study of the diffuse, polarized, radio emission from the giant lobes of the nearest radio galaxy, Centaurus A. After removal of the smooth Galactic foreground RM component, using an ensemble of background source RMs located outside the giant lobes, we are left with a residual RM signal associated with the giant lobes. We find that the most likely origin of this residual RM is from thermal material mixed throughout the relativistic lobe plasma. The alternative possibility of a thin-skin/boundary layer of magnetoionic material swept up by the expansion of the lobes is highly unlikely since it requires, at least, an order of magnitude enhancement of the swept-up gas over the expected intragroup density on these scales. Strong depolarization observed from 2.3 to 0.96 GHz also supports the presence of a significant amount of thermal gas within the lobes; although depolarization solely due to RM fluctuations in a foreground Faraday screen on scales smaller than the beam cannot be ruled out. Considering the internal Faraday rotation scenario, we find a thermal gas number density of ∼10−4 cm−3, implying a total gas mass of ∼1010 M ☉ within the lobes. The thermal pressure associated with this gas (with temperature kT ∼ 0.5 keV, obtained from recent X-ray results) is approximately equal to the non-thermal pressure, indicating that over the volume of the lobes, there is approximate equipartition between the thermal gas, radio-emitting electrons, and magnetic field (and potentially any relativistic protons present).
Testing the Dark Matter Annihilation Model for the WMAP Haze

Analyses have found a "haze" of anomalous microwave emission surrounding the Galactic Center in the WMAP sky maps. A recent study using Fermi data detected a similar haze in the gamma-ray. Several studies have modeled these hazes as radiation from the leptonic byproducts of dark matter annihilations, and arguably no convincing astrophysical alternative has been suggested. We discuss the characteristics of astrophysical cosmic ray sources that could potentially explain this microwave and gamma-ray emission. The most promising astrophysical scenarios involve cosmic ray sources that are clustered such that many fall within ~1 kpc of the Galactic Center. For example, we show that several hundred Galactic Center supernovae in the last million years plus a diffusion-hardened electron spectrum may be consistent with present constraints on this emission. Alternatively, it could be due to a burst of activity probably associated with Sagittarius A* occurring ~1 Myr ago and producing >10^51 erg in cosmic ray electrons. Different models predict different trends for the spectral index of the microwave and gamma-ray spectrum as a function of angle from the Galactic Center that should be robust to cosmic ray propagation uncertainties. In particular, if the haze is from dark matter annihilations, it should have a very hard microwave and gamma-ray spectrum for which the spectral shape does not change significantly with angle, which we argue would be difficult to achieve with any astrophysical mechanism. Observations with the Planck and Fermi satellites can distinguish between viable haze models using these signatures.
THE RELATIONSHIP BETWEEN BLACK HOLE GROWTH AND STAR FORMATION IN SEYFERT GALAXIES

We present estimates of black hole accretion rates (BHARs) and nuclear, extended, and total star formation rates for a complete sample of Seyfert galaxies. Using data from the Spitzer Space Telescope, we measure the active galactic nucleus (AGN) luminosity using the [O iv] λ25. 89 μm emission line and the star-forming luminosity using the 11.3 μm aromatic feature and extended 24 μm continuum emission. We find that black hole growth is strongly correlated with nuclear (r < 1 kpc) star formation, but only weakly correlated with extended (r > 1 kpc) star formation in the host galaxy. In particular, the nuclear star formation rate (SFR) traced by the 11.3 μm aromatic feature follows a relationship with the BHAR of the form , with an observed scatter of 0.5 dex. This SFR–BHAR relationship persists when additional star formation in physically matched r = 1 kpc apertures is included, taking the form . However, the relationship becomes almost indiscernible when total SFRs are considered. This suggests a physical connection between the gas on sub-kiloparsec and sub-parsec scales in local Seyfert galaxies that is not related to external processes in the host galaxy. It also suggests that the observed scaling between star formation and black hole growth for samples of AGNs will depend on whether the star formation is dominated by a nuclear or an extended component. We estimate the integrated black hole and bulge growth that occurs in these galaxies and find that an AGN duty cycle of 5%–10% would maintain the ratio between black hole and bulge masses seen in the local universe.
CHANDRA HIGH-RESOLUTION SPECTROSCOPY OF THE CIRCUMNUCLEAR MATTER IN THE BROAD-LINE RADIO GALAXY 3C 445

We present evidence for X-ray line emitting and absorbing gas in the nucleus of the broad-line radio galaxy 3C 445. A 200 ks Chandra Low Energy Transmission Grating observation of 3C 445 reveals the presence of several highly ionized emission lines in the soft X-ray spectrum, primarily from the He- and H-like ions of O, Ne, Mg, and Si. Radiative recombination emission is detected from O vii and O viii, indicating that the emitting gas is photoionized. The He-like emission appears to be resolved into forbidden and intercombination line components, which implies a high density of >1010 cm−3, while the oxygen lines are velocity broadened with a mean width of ∼2600 km s−1 (FWHM). The density and widths of the ionized lines indicate an origin of the gas on sub-parsec scales in the broad-line region. The X-ray continuum of 3C 445 is heavily obscured either by a partial coverer or by a photoionized absorber of column density NH = 2 × 1023 cm−2 and ionization parameter log ξ = 1.4 erg cm s−1. However, the view of the X-ray line emission is unobscured, which requires the absorber to be located at radii well within any parsec-scale molecular torus. Instead we suggest that the X-ray absorber in 3C 445 may be associated with an outflowing but clumpy accretion disk wind, with an observed outflow velocity of ∼10, 000 km s−1.
Factors influencing continuance intention of online shopping of generation Y and Z during the new normal in Vietnam

Abstract This study investigated the determinants of online shopping continuance intention of Generation Y and Z during the new normal. A conceptual framework, which was an extension of the Technology Acceptance Model, was empirically tested using partial least squares structural equation modelling, multi-group analysis technique, and the data collected from 847 Gen Y-ers and Gen Z-ers in Hanoi, Vietnam during March 2022. The results revealed that facilitators of repurchase intention included perceived usefulness, perceived ease of use, satisfaction, and environmental awareness while perceived risks of online shopping served as a barrier. Notably, the barrier was found to affect Gen Y’s repurchase intention more severely. Personalization was not directly associated with the intention but had strong indirect effects through perceived usefulness, perceived ease of use, and satisfaction. The risk of COVID-19 was not a predictor of online repurchase intention. Understanding of the continuance intention of online shopping among consumers from different generations in an emerging country during the new normal may aid to enhance the quality of decision-making. Specifically, platforms and sellers should adopt customized marketing programs towards Gen Y and Gen Z. Additionally, a user-friendly and informative purchasing process with personalized features should be formulated. Demonstrating online shopping as a green behavior would be useful. This study differs from earlier research by considering and comparing factors influencing the intention to keep shopping online of Gen Y and Gen Z in a developing country when the COVID-19 is well controlled.
Series-expansion thermal tensor network approach for quantum lattice models

We propose a series-expansion thermal tensor network (SETTN) approach for efficient simulations of quantum lattice models. This continuous-time SETTN method is based on the numerically exact Taylor series expansion of the equilibrium density operator ${e}^{\ensuremath{-}\ensuremath{\beta}H}$ (with $H$ the total Hamiltonian and $\ensuremath{\beta}$ the imaginary time), and is thus Trotter-error free. We discover, through simulating XXZ spin chain and square-lattice quantum Ising models, that not only the Hamiltonian $H$, but also its powers ${H}^{n}$, can be efficiently expressed as matrix product operators, which enables us to calculate with high precision the equilibrium and dynamical properties of quantum lattice models at finite temperatures. Our SETTN method provides an alternative to conventional Trotter-Suzuki renormalization-group (RG) approaches, and achieves a very high standard of thermal RG simulations in terms of accuracy and flexibility.
Integrable discrete nonautonomous quad-equations as Bäcklund auto-transformations for known Volterra and Toda type semidiscrete equations

We construct integrable discrete nonautonomous quad-equations as Bäcklund autotransformations for known Volterra and Toda type semidiscrete equations, some of which are also nonautonomous. Additional examples of this kind are found by using transformations of discrete equations which are invertible on their solutions. In this way we obtain integrable examples of different types: discrete analogs of the sine-Gordon equation, the Liouville equation and the dressing chain of Shabat. For Liouville type equations we construct general solutions, using a specific linearization. For sine-Gordon type equations we find generalized symmetries, conservation laws and L—A pairs.
The Green Function for Elliptic Systems in Two Dimensions

We construct the fundamental solution or Green function for a divergence form elliptic system in two dimensions with bounded and measurable coefficients. Our main goal is construct the Green function for the operator with mixed boundary conditions in a Lipschitz domain. Thus we specify Dirichlet data on part of the boundary and Neumann data on the remainder of the boundary. We require a corkscrew or non-tangential accessibility condition on the set where we specify Dirichlet boundary conditions. Our proof proceeds by defining a variant of the space BMO(Ω) that is adapted to the boundary conditions and showing that the solution exists in this space. We also give a construction of the Green function with Neumann boundary conditions and the fundamental solution in the plane.
On the buildup of massive early-type galaxies at z≲1 I. Reconciling their hierarchical assembly with mass downsizing

Context. Several studies have tried to ascertain whether the increase in abundance of the early-type galaxies (E-S0a's) with time is mainly due to major mergers, but have reached opposite conclusions. Aims. We have tested it directly through semi-analytical modelling, quantifying the possible contribution of the observed major mergers to the evolution of the high-mass end of the galaxy luminosity function (LF). Methods. The model analyses the backwards-in-time evolution of the massive early-type galaxies with log(M_*/M_⨀) > 11 at z∼0 (mETGs) under the hypothesis that each major merger leads to an early-type galaxy. The model considers only the major mergers strictly reported by observations at each redshift and assumes that gas-rich major mergers experience transitory phases as dust-reddened, star-forming galaxies (DSFs). Results. The model is able to reproduce the observed evolution of the galaxy LFs at z ≲ 1 simultaneously for different rest-frame bands (B, I, and K) and for different selection criteria on colour and morphology. It also provides a framework in which apparently contradictory results on the recent evolution of the LF of massive red galaxies can be reconciled, just considering that observed samples of red galaxies can be significantly contaminated by DSFs. The model proves that it is feasible to build up ∼50-60% of the present-day number density of mETGs at z≲1 through the coordinated action of wet, mixed, and dry major mergers, fulfilling global trends that are in general agreement with mass downsizing. The bulk of this assembly takes place during ∼1 Gyr elapsed at 0.8 < z < 1, providing a straightforward explanation for the observed fact that redshift z ∼ 0.8 is a transition epoch in the formation of mETGs. The gas-rich progenitors of these recently assembled mETGs reproduce the observed excess by a factor of ∼4-5 of late-type galaxies at 0.8 < z < 1 naturally, as compared to pure luminosity evolution (PLE) models. Conclusions. The model suggests that major mergers have been the main driver for the observed mass migration from the massive end of the blue galaxy cloud to that of the red sequence in the past ∼8 Gyr.
Improving IEEE 802.11ax UORA Performance: Comparison of Reinforcement Learning and Heuristic Approaches

Machine learning (ML) has gained attention from the network research community because it can help solve difficult problems and potentially lead to groundbreaking achievements. In the Wi-Fi domain, ML is applied to solve challenges such as efficient channel access and fair coexistence with other technologies in unlicensed bands. In this paper, we address the performance of uplink orthogonal frequency division multiple random access (UORA) in IEEE 802.11ax networks. Optimization of UORA is a good case for applying ML because of its inherent complexity and dependence on situation and time-dependent parameters. In particular, we use deep reinforcement learning to tune UORA parameters. Our simulation results show that even though the ML-based solution leads to close to optimal results, its operation is comparable to a much simpler, non-ML heuristic. Therefore, we conclude that ML-based solutions to improve IEEE 802.11 performance need not exceed well-designed heuristics.
Use of Chipless RFID as a Passive, Printable Sensor Technology for Aerospace Strain and Temperature Monitoring

This paper was concerned with the current level of progress towards the development of chipless radio frequency identification (RFID) sensors that are capable of sensing strain and temperature. More specifically, it was interested in the possibility that the resulting devices could be used as a passive wireless structural health monitoring (SHM) sensor technology that could be printed in situ. This work contains the development and performance characterization results for both novel strain and novel temperature sensor designs with resulting sensitivities of 9.77 MHz/%ε and 0.88 MHz/°C, respectively. Furthermore, a detailed discussion on the interrogation system required to meet the relevant aerospace sensing requirements was also discussed, and several methods were explored to enhance the multi-sensor support capabilities of this technology.
THE MICROLENSING EVENT RATE AND OPTICAL DEPTH TOWARD THE GALACTIC BULGE FROM MOA-II

We present measurements of the microlensing optical depth and event rate toward the Galactic Bulge (GB) based on two years of the MOA-II survey. This sample contains ∼1000 microlensing events, with an Einstein radius crossing time of tE ⩽ 200 days in 22 bulge fields covering ∼42 deg2 between −5° < l < 10° and −7° < b < −1°. Our event rate and optical depth analysis uses 474 events with well-defined microlensing parameters. In the central fields with |l| < 5°, we find an event rate of Γ = [2.39 ± 1.1]e[0.60 ± 0.05](3 − |b|) × 10−5 star−1 yr−1 and an optical depth (for events with tE ⩽ 200 days) of τ200 = [2.35 ± 0.18]e[0.51 ± 0.07](3 − |b|) × 10−6 for the 427 events, using all sources brighter than Is ⩽ 20 mag. The distribution of observed fields is centered at (l, b) = (0.°38, −3.°72). We find that the event rate is maximized at low latitudes and a longitude of l ≈ 1°. For the 111 events in 3.2 deg2 of the central GB at |b| ⩽ 3. °0 and 0. °0 ⩽ l ⩽ 2. °0, centered at (l, b) = (0.°97, −2.°26), we find star−1 yr−1 and . We also consider a red clump giant (RCG) star sample with Is < 17.5, and we find that the event rate for the RCG sample is slightly lower than but consistent with the all-source event rate. The main difference is the lack of long duration events in the RCG sample due to a known selection effect. Our results are consistent with previous optical depth measurements, but they are somewhat lower than previous all-source measurements, and slightly higher than previous RCG optical depth measurements. This suggests that the previously observed difference in optical depth measurements between all-source and RCG samples may largely be due to statistical fluctuations. These event rate measurements toward the central GB are necessary to predict the microlensing event rate and to optimize the survey fields in future space missions such as Wide Field Infrared Space Telescope.
Star Formation Law in the Milky Way

The Schmidt law (SF law) in the Milky Way was investigated using 3D distribution maps of HII regions, HI and molecular (\Htwo) gases with spatial resolutions of $\sim 1$ kpc in the Galactic plane and a few tens of pc in the vertical direction. HII regions were shown to be distributed in a star-forming (SF) disk with nearly constant vertical full thickness 92 pc in spatial coincidence with the molecular gas disk. The vertically averaged volume star formation rate (SFR) $\rho_{\rm SFR}$ in the SF disk is related to the surface SFR $\Sigma_{\rm SFR}$ by $\rho_{\rm SFR} /[{\rm M_\odot y^{-1} kpc^{-3}}] =9.26\times \Sigma_{\rm SFR}/[{\rm M_\odot y^{-1} kpc^{-2}}]$. The SF law fitted by a single power law of gas density in the form of $\Sigma_{\rm SFR} \propto \rho_{\rm SFR} \propto \rho_{\rm gas}^\alpha$ and $\propto \Sigma_{\rm gas}^\beta$ showed indices of $\alpha=0.78 \pm 0.05$ for $\rho_{\rm H_2}$ and $2.15 \pm 0.08$ for $\rho_{\rm total}$, and $\beta=1.14\pm 0.23$ for $\Sigma_{\rm total}$, where $\rho$ and $\Sigma$ denote volume and surface densities, respectively. The star formation rate is shown to be directly related to the molecular gas, but indirectly to HI and total gas densities. The dependence of the SF law on the gaseous phase is explained by the phase transition theory between HI and H$_2$ gases.
Double Solids, Categories and Non-Rationality

Abstract This paper suggests a new approach to questions of rationality of 3-folds based on category theory. Following work by Ballard et al., we enhance constructions of Kuznetsov by introducing Noether–Lefschetz spectra: an interplay between Orlov spectra and Hochschild homology. The main goal of this paper is to suggest a series of interesting examples where the above techniques might apply. We start by constructing a sextic double solid X with 35 nodes and torsion in H3(X, ℤ). This is a novelty: after the classical example of Artin and Mumford, this is the second example of a Fano 3-fold with a torsion in the third integer homology group. In particular, X is non-rational. We consider other examples as well: V10 with 10 singular points, and the double covering of a quadric ramified in an octic with 20 nodal singular points. After analysing the geometry of their Landau–Ginzburg models, we suggest a general non-rationality picture based on homological mirror symmetry and category theory.