Search

The model of chain of springs and masses, originating from works of Schr\"odinger (1914) and Pater (1974), is found suitable as an analytical description of dynamics of layers in oriented FCC crystals. An analytical extension of that model has been provided for the case of linear-in-time ramp pressure applied to sample surface. Examples are provided of molecular dynamics (MD) simulations confirming the usefulness of the model in description of dynamic effects in steal 310S under pressure. For large sizes of samples and for long times, an improved version of proposed earlier interlayer potential has been provided for the use in lammps, resulting in a perfect harmonic inter-layer interaction, compensating the inclusion of higher-order terms in potential energy, proportional to x^4 . The results of MD simulations suggest that the dynamics of the model of chain of springs and masses of perfectly ordered matter is describable by stretched-exponential time functions and it is characterized by simple scaling properties in time.

Combining Atacama Large Millimeter/sub-millimeter Array CO(2-1) mapping and JWST near- and mid-infrared imaging, we characterize the relationship between CO(2-1) and polycyclic aromatic hydrocarbon (PAH) emission at ~100 pc resolution in 66 nearby star-forming galaxies, expanding the sample size from previous ~100 pc resolution studies by more than an order of magnitude. Focusing on regions of galaxies where most of the gas is likely to be molecular, we find strong correlations between CO(2-1) and 3.3 micron, 7.7 micron, and 11.3 micron PAH emission, estimated from JWST's F335M, F770W, and F1130W filters. We derive power law relations between CO(2-1) and PAH emission, which have indices in the range 0.8-1.2, implying relatively weak variations in the observed CO-to-PAH ratios across the regions that we study. We find that CO-to-PAH ratios and scaling relationships near HII regions are similar to those in diffuse sight lines. The main difference between the two types of regions is that sight lines near HII regions show higher intensities in all tracers. Galaxy centers, on the other hand, show higher overall intensities and enhanced CO-to-PAH ratios compared to galaxy disks. Individual galaxies show 0.19 dex scatter in the normalization of CO at fixed I_PAH and this normalization anti-correlates with specific star formation rate (SFR/M*) and correlates with stellar mass. We provide a prescription that accounts for these galaxy-to-galaxy variations and represents our best current empirical predictor to estimate CO(2-1) intensity from PAH emission, which allows one to take advantage of JWST's excellent sensitivity and resolution to trace cold gas., Comment: 21 pages, 4 figures, 3 tables. Submitted to ApJ

Theoretical considerations are made for the nuclear excitation from the ground state to the 8 eV $^{229m}$Th isomer via near-resonant electron transitions in Sb-like ($q=39+$) thorium ions. The energy of the first excited atomic state ($J=7/2$) in the $^{229}$Th$^{39+}$ ion is estimated to be 8.308$\pm$0.011 eV, which is very close to the new reference value for the $^{229m}$Th nuclear isomer energy, 8.338$\pm$0.024 eV [Kraemer et al., Nature 617, 706 (2023)]. It was found that within the uncertainty range of both atomic and nuclear excitation energies, the rate of nuclear excitation by electron transition can vary by more than 20 orders of magnitude. Our results indicate that the upper theoretical limit for the $^{229m}$Th isomer excitation rate reaches an enormous value of $1.05\times10^{16}$ s$^{-1}$ at resonance ($\Delta=0$ meV). Additionally, it was shown that using an electron beam ion trap (EBIT), the production of the $^{229}$Th isomer can reach rates ranging from tenths to approximately $6\times10^{19}$ s$^{-1}$. Thus, EBIT experimental studies could serve as an extremely sensitive tool for the independent verification of the excitation energy of the isomeric state in the $^{229}$Th nucleus.

Let $\mathfrak{F}$ be a nonarchimedean local field of residual characteristic $p$, and let $G$ denote the group of $\mathfrak{F}$-points of a connected reductive group over $\mathfrak{F}$. For an open compact subgroup $\mathcal{U}$ of $G$ and a unital commutative ring $k$, we let $\mathbf{X}_{\mathcal{U}}$ denote the space of compactly supported $k$-valued functions on $G/\mathcal{U}$. Building on work of Ollivier--Schneider, we investigate the graded $\textrm{Ext}$-algebra $E_{\mathcal{U}}^* := \textrm{Ext}_G^*(\mathbf{X}_{\mathcal{U}},\mathbf{X}_{\mathcal{U}})^{\textrm{op}}$. In particular, we describe the Yoneda product, an involutive anti-automorphism, and (when $k$ is a field of characteristic $p$ and $\mathcal{U}$ has no $p$-torsion) a duality operation. We allow for the reductive group to be non-split, and for the open compact subgroup $\mathcal{U}$ to be non-pro-$p$. Specializing further to the case $G = \textrm{SL}_2(\mathbb{Q}_p)$ with $p \geq 5$ and a coefficient field of characteristic $p$, we obtain more precise results when $\mathcal{U}$ is equal to an Iwahori subgroup $J$ or a hyperspecial maximal compact subgroup $K$. In particular, we compute the structure of $E_J^*$ as an $E_J^0$-bimodule, obtain an explicit description of the center $\mathcal{Z}(E_J^*)$ of $E_J^*$, and construct a surjective morphism of algebras $\mathcal{Z}(E_J^*) \longrightarrow E_K^*$ (analogous to the compatibility between Bernstein and Satake isomorphisms in characteristic 0). From this we deduce the (somewhat surprising) fact that $E_K^*$ is not graded-commutative, contrary to what happens for almost all $\ell$-modular characteristics., Comment: 52 pages, with an appendix joint with David Schwein. Comments welcome!

Let $F$ be a finite unramified extension of $\mathbb{Q}_p$ with ring of integers $\mathcal{O}_F$, and let $\mathbf{G}$ denote a split, connected reductive group over $\mathcal{O}_F$. We fix a Borel subgroup $\mathbf{B} = \mathbf{T}\mathbf{U}$ with maximal torus $\mathbf{T}$ and unipotent radical $\mathbf{U}$, and let $L(\lambda)$ denote an irreducible representation of $G_0 := \mathbf{G}(\mathcal{O}_F)$ with coefficients in a sufficiently large field of characteristic $p$. Set $G := \mathbf{G}(F)$, etc. Assuming $\lambda$ is a $p$-small and sufficiently regular character and that $p - 1$ is greater than the Coxeter number of $\mathbf{G}$, we show that the complex $L(U,\textrm{c-ind}_{G_0}^{G}(L(\lambda)))$ splits as the orthogonal direct sum of its cohomology objects in the derived category of smooth $T$-representations in characteristic $p$. (Here $L(U, -)$ denotes Heyer's left adjoint of parabolic induction, from the derived category of smooth $G$-representations to the derived category of smooth $T$-representations.) Consequently, this gives rise to a collection of morphisms of graded spherical Hecke algebras $$\displaystyle{\bigoplus_{i \in \mathbb{Z}}\textrm{Ext}_{G}^{i}\left(\textrm{c-ind}_{G_0}^{G}(L(\lambda)),~\textrm{c-ind}_{G_0}^{G}(L(\lambda))\right) \longrightarrow \bigoplus_{i \in \mathbb{Z}}\textrm{Ext}_{T}^{i}\left(\textrm{c-ind}_{T_0}^{T}(L^n(U_0,L(\lambda))),~\textrm{c-ind}_{T_0}^{T}(L^n(U_0,L(\lambda)))\right)}$$ indexed by $n=-[F:\mathbb{Q}_p]\dim(\mathbf{U}), \ldots, 0$, which we refer to as derived Satake morphisms. For $\lambda=0$ and $n=0$, this recovers the graded mod $p$ Satake homomorphism constructed by Ronchetti. We also give some partial results for general standard parabolic subgroups $\mathbf{P} = \mathbf{M}\mathbf{N} \subset \mathbf{G}$., Comment: 40 pages. Comments welcome!

POLAR-2 is a dedicated gamma-ray polarimeter currently foreseen to be launched towards the China Space Station around 2027. The design of the detector is based on the legacy of its predecessor mission POLAR which was launched in 2016. POLAR-2 aims to measure the polarization of the Gamma-ray Burst prompt emission within the 30-800 keV energy range. Thanks to its high sensitivity to gamma-ray polarization, as well as its large effective area, POLAR-2 will provide the most precise measurements of this type to date. Such measurements are key to improve our understanding of the astrophysical processes responsible for Gamma-Ray Bursts. The detector consists of a segmented array of plastic scintillator bars, each one of which is read out by a Silicon PhotoMultiplier channel. The flight model of POLAR-2 will contain a total of 6400 scintillators. These are divided into 100 groups of 64 bars each, in so-called polarimeter modules. In recent years, the collaboration has designed and produced the first prototypes of these polarimeter modules and subjected these to space qualification tests. In addition, in April 2023, the first of these modules were calibrated using fully polarized gamma-ray beams at the European Synchrotron Radiation Facility (ESRF) in France. In this work, we will present the results of this calibration campaign and compare these to the simulated performance of the POLAR-2 modules. Potential improvements to the design are also discussed. Finally, the measurements are used, in combination with the verified simulation framework, to estimate the scientific performance of the full POLAR-2 detector and compare it to its predecessor., Comment: Accepted for publication in JINST

The $4d \to 3p$ x-ray transitions in Cu- and Ni-like tungsten ions have been studied theoretically. The multiconfiguration Dirac-Hartree-Fock (MCDHF) method and the large-scale relativistic configuration-interaction (CI) method have been employed in order to take into account electron correlation effects on the wavelengths and transition rates. It was found that the wavelengths and transition rates obtained from the MCDHF-CI method depend strongly on the size and the type of the active space used in the calculations. It has been found that extending the active space of orbitals without careful control of the configuration state function base does not always lead to good quality MCDHF-CI results for highly ionized tungsten ions.

Results of relativistic calculations of nuclear magnetic resonance shielding tensors ($\sigma$) for the thallium monocation (Tl$^+$), thallium hydride (TlH) and thallium halides (TlF, TlCl, TlBr, TlI, and TlAt) are presented as obtained within a four-component polarization propagator formalism and a two-component linear response approach within the zeroth-order regular approximation. Additionally, some quantum electrodynamical (QED) effects on those NMR shieldings are estimated. A strong dependence of $\sigma$(Tl) on the bonding partner is found, together with a very weak dependence of QED effects with them. In order to explain the trends observed, the excitation patterns associated with relativistic $ee$ (or paramagnetic-like) and $pp$ (or diamagnetic-like) contributions to $\sigma$ are analyzed. For this purpose, also the electronic spin-free and spin-dependent contributions are separated within the two-component zeroth-order regular approximation, and the influence of spin-orbit coupling on involved molecular orbitals is studied, which allows for a thorough understanding of the underlying mechanisms.

We study the ferromagnetic transverse-field Ising model with quenched disorder at $T = 0$ in one and two dimensions by means of stochastic series expansion quantum Monte Carlo simulations using a rigorous zero-temperature scheme. Using a sample-replication method and averaged Binder ratios, we determine the critical shift and width exponents $\nu_\mathrm{s}$ and $\nu_\mathrm{w}$ as well as unbiased critical points by finite-size scaling. Further, scaling of the disorder-averaged magnetisation at the critical point is used to determine the order-parameter critical exponent $\beta$ and the critical exponent $\nu_{\mathrm{av}}$ of the average correlation length. The dynamic scaling in the Griffiths phase is investigated by measuring the local susceptibility in the disordered phase and the dynamic exponent $z'$ is extracted. By applying various finite-size scaling protocols, we provide an extensive and comprehensive comparison between the different approaches on equal footing. The emphasis on effective zero-temperature simulations resolves several inconsistencies in existing literature., Comment: 46 pages, 28 figures

Magnetic vortices are topological spin structures frequently found in ferromagnets, yet novel to antiferromagnets. By combining experiment and theory, we demonstrate that in a nanostructured antiferromagnetic-ferromagnetic NiO(111)-Fe(110) bilayer, a magnetic vortex is naturally stabilized by magnetostatic interactions in the ferromagnet and is imprinted onto the adjacent antiferromagnet via interface exchange coupling. We use micromagnetic simulations to construct a corresponding phase diagram of the stability of the imprinted antiferromagnetic vortex state. Our in depth analysis reveals that the interplay between interface exchange coupling and the antiferromagnet magnetic anisotropy plays a crucial role in locally reorienting the N\'eel vector out-of-plane in the prototypical in-plane antiferromagnet NiO and thereby stabilizing the vortices in the antiferromagnet.

Long-range interactions are relevant for a large variety of quantum systems in quantum optics and condensed matter physics. In particular, the control of quantum-optical platforms promises to gain deep insights in quantum-critical properties induced by the long-range nature of interactions. From a theoretical perspective, long-range interactions are notoriously complicated to treat. Here, we give an overview of recent advancements to investigate quantum magnets with long-range interactions focusing on two techniques based on Monte Carlo integration. First, the method of perturbative continuous unitary transformations where classical Monte Carlo integration is applied within the embedding scheme of white graphs. This linked-cluster expansion allows to extract high-order series expansions of energies and observables in the thermodynamic limit. Second, stochastic series expansion quantum Monte Carlo which enables calculations on large finite systems. Finite-size scaling can then be used to determine physical properties of the infinite system. In recent years, both techniques have been applied successfully to one- and two-dimensional quantum magnets involving long-range Ising, XY, and Heisenberg interactions on various bipartite and non-bipartite lattices. Here, we summarise the obtained quantum-critical properties including critical exponents for all these systems in a coherent way. Further, we review how long-range interactions are used to study quantum phase transitions above the upper critical dimension and the scaling techniques to extract these quantum critical properties from the numerical calculations., Comment: 141 pages, 38 figures

We investigate the quantum robustness of the topological order in the toric code on the honeycomb lattice in the presence of a uniform parallel field. For a field in $z$-direction, the low-energy physics is in the flux-free sector and can be mapped to the transverse-field Ising model on the honeycomb lattice. One finds a second-order quantum phase transition in the 3D Ising$^\star$ universality class for both signs of the field. The same is true for a postive field in $x$-direction where an analogue mapping in the charge-free sector yields a ferromagnetic transverse-field Ising model on the triangular lattice and the phase transition is still 3D Ising$^\star$. In contrast, for negative $x$-field, the charge-free sector is mapped to the highly frustrated antiferromagnetic transverse-field Ising model on the triangular lattice which is known to host a quantum phase transition in the 3D XY$^\star$ universality class. Further, the charge-free sector does not always contain the low-energy physics for negative $x$-fields and a first-order phase transition to the polarized phase in the charge-full sector takes place at larger negative field values. We quantify the location of this transition by comparing quantum Monte Carlo simulations and high-field series expansions. The full extension of the topological phase in the presence of $x$- and $z$-fields is determined by perturbative linked-cluster expansions using a full graph decomposition. Extrapolating the high-order series of the charge and the flux gap allows to estimate critical exponents of the gap closing. This analysis indicates that the topological order breaks down by critical lines of 3D Ising$^\star$ and 3D XY$^\star$ type with interesting potential multi-critical crossing points. All findings for the toric code on the honeycomb lattice can be transferred exactly to the toric code on the triangular lattice., Comment: 26 pages, 8 figures

We study the low-field ground-state (GS) properties of the antiferromagnetic transverse-field Ising model with long-range interactions (afLRTFIM) on the triangular lattice. We use the method of perturbative continuous unitary transformations (pCUT) to derive an effective model for the degenerate GS space of the antiferromagnetic nearest-neighbour (NN) Ising model on a finite system, by treating the transverse-field (TF) and the long-range interactions (LRI) as a perturbation. We determine a level-crossing between the plain stripe phase at small TF and the clock-ordered phase at intermediate TF at $h\cong0.129$ for $\alpha=6$, $N=36$ spins in order three perturbation theory. We discuss the qualitative layout of the quantum phase diagram of the afLRTFIM on the triangular lattice., Comment: 3 pages, 1 figure

We present new observations of the central 1 kpc of the M 82 starburst obtained with the James Webb Space Telescope (JWST) near-infrared camera (NIRCam) instrument at a resolution ~0.05"-0.1" (~1-2 pc). The data comprises images in three mostly continuum filters (F140M, F250M, and F360M), and filters that contain [FeII] (F164N), H2 v=1-0 (F212N), and the 3.3 um PAH feature (F335M). We find prominent plumes of PAH emission extending outward from the central starburst region, together with a network of complex filamentary substructure and edge-brightened bubble-like features. The structure of the PAH emission closely resembles that of the ionized gas, as revealed in Paschen alpha and free-free radio emission. We discuss the origin of the structure, and suggest the PAHs are embedded in a combination of neutral, molecular, and photoionized gas., Comment: Submitted to The Astrophysical Journal

We investigate the quantum phase diagram of the $J_1$-$J_2$-$J_3$ antiferromagnetic transverse-field Ising model on the ruby lattice. In the low-field limit we derive an effective quantum dimer model, analyzing how the extensive ground-state degeneracy at zero field is lifted by an order-by-disorder scenario. We support our analysis by studying the gap-closing of the high-field phase using series expansions. For $J_2>J_3$, we find a columnar phase at low fields, followed by a clock-ordered phase stabilized by resonating plaquettes at intermediate field values, and an emergent 3d-XY quantum phase transition to the polarized high-field phase. For $J_3>J_2$, an order-by-disorder mechanism stabilizes a distinct $k=(0,0)$ order and a quantum phase transition in the 3d-Ising universality class is observed. Further, we discuss the possible implementation of the columnar- and clock-ordered phase in existing Rydberg atom quantum simulators. When taking into account the full algebraically decaying long-range interactions on the ruby lattice, we find that long-range interactions favor the same ground state as the quantum fluctuations induced by a transverse field, which could make the ruby lattice a promising candidate for the realization of a clock-ordered phase., Comment: 23 pages, 16 figures

We analyse the ground-state quantum phase diagram of hardcore Bosons interacting with repulsive dipolar potentials. The bosons dynamics is described by the extended-Bose-Hubbard Hamiltonian on a two-dimensional lattice. The ground state results from the interplay between the lattice geometry and the long-range interactions, which we account for by means of a classical spin mean-field approach limited by the size of the considered unit cells. This extended classical spin mean-field theory accounts for the long-range density-density interaction without truncation. We consider three different lattice geometries: square, honeycomb, and triangular. In the limit of zero hopping the ground state is always a devil's staircase of solid (gapped) phases. Such crystalline phases with broken translational symmetry are robust with respect to finite hopping amplitudes. At intermediate hopping amplitudes, these gapped phases melt, giving rise to various lattice supersolid phases, which can have exotic features with multiple sublattice densities. At sufficiently large hoppings the ground state is a superfluid. The stability of phases predicted by our approach is gauged by comparison to the known quantum phase diagrams of the Bose-Hubbard model with nearest-neighbour interactions as well as quantum Monte Carlo simulations for the dipolar case on the square and triangular lattice. Our results are of immediate relevance for experimental realisations of self-organised crystalline ordering patterns in analogue quantum simulators, e.g., with ultracold dipolar atoms in an optical lattice., Comment: 35 pages, 10 figures

Anharmonic inter-atomic potential x to power of n, n>1, has been used in molecular dynamics (MD) simulations of stress dynamics of FCC oriented crystal. The model of the chain of masses and springs is found as a convenient and accurate description of simulation results, with masses representing the crystallographic planes. The dynamics of oscillations of two planes is found analytically to be given by Euler beta functions, and its scaling with non-linearity parameter and amplitude of oscillations, or applied shear pressure is discussed on examples of time dependencies of displacements, velocities, and forces acting on masses (planes). The dynamics of stress penetration from the surface of the sample with multiply-planes (an anharmonic crystal) towards its interior is confirmed to be given exactly as a series of Bessel functions, when n=2 (Schrodinger and Pater solutions). When n<>2 the stress dynamics (wave propagation) in bulk material remains qualitatively of the same nature as in the linear case. In particular, results suggest that the quasi-linear relationship between frequency and wave number is preserved. Speed of the transverse sound component, dependent on sound wave amplitude, is found to be a strongly decreasing function of n. The results are useful in the analysis of any MD simulations under pressure, as they help to understand the dynamics of pressure retarded effects, as well help design the proper methodology of performing MD simulations, such as studies of dynamics of dislocations., Comment: 36 pages, 20 figures, 1 movie (hard linked in the article, available also in source)

High-accuracy Multi-Configuration Dirac-Hartree-Fock calculations of ionization energies with Configuration Interaction have been carried out for tungsten ions (W$^{2+}$ to W$^{71+}$) by means of the GRASP code. A comparison with other available experimental and theoretical data, including those calculated by FAC code based on the Dirac-Hartree-Fock-Slater method and with the NIST database has been presented. This work provides a new set of recommended ionization energy values for tungsten ions using state-of-the-art theoretical calculations with uncertainties ranging from 0.07 eV to 0.4 eV, which seems to be a significant improvement over the previous reference uncertainties.

We studied the influence of a magnetic field (MF) on epitaxial growth and magnetic properties of Fe(001) films deposited on MgO(001). Thanks to modular sample holders and a specialized manipulator in our multi-chamber ultrahigh vacuum system, the films could be deposited and annealed in an in-plane MF of 100 mT. In situ scanning tunnelling microscopy showed that MF had a strong influence on the film morphology, and, in particular, on the structure of surface steps. The magnetic properties were studied ex situ using magneto-optic Kerr effect (MOKE) magnetometry and microscopy. We showed that the moderate in-plane magnetic field applied during growth has the visible impact on the magnetic properties. The observed angular dependence of the MOKE loops and domain structures were discussed based on a magnetization reversal model. In particular we found that magnetization reversal occurs via 90{\deg} domains and the reversal differs for the no-field and in-field grown samples, in correlation with the film morphology.

Since their discoveries in 1967, Gamma-Ray Bursts (GRBs) continue to be one of the most researched objects in astrophysics. Multi-messenger observations are key to gaining a deeper understanding of these events. In order to facilitate such measurements, fast and accurate localization of the gamma-ray prompt emission is required. As traditional localization techniques are often time consuming or prone to significant systematic errors, here we present a novel method which can be applied on the POLAR-2 observatory. POLAR-2 is a dedicated GRB polarimeter, which will be launched towards the China Space Station (CSS) in 2025. The CSS provides POLAR-2 access to a GPU, which makes it possible and advantageous to run a Deep Learning model on it. In this work, we explore the possibility to identify GRBs in real time and to infer their location and spectra with deep learning models. Using POLAR simulations and data, a feasibility experiment was performed to implement this method on POLAR-2. Our results indicate that using this method, in combination with real time data downlinking capabilities, POLAR-2 will be able to provide accurate localization alerts within 2 minutes of the GRB onset., Comment: Proceeding from the 38th International Cosmic Ray Conference (ICRC2023), 8 pages

Let $p$ be a prime number and $F/F^+$ a CM extension of a totally real field such that every place of $F^+$ above $p$ is unramified and inert in $F$. We fix a finite place $v$ of $F^+$ above $p$, and let $\overline{r}: \textrm{Gal}(\overline{F^+}/F^+) \longrightarrow {}^C\textrm{U}_{1,1}(\overline{\mathbb{F}}_p)$ be a modular $L$-parameter valued in the $C$-group of a rank 2 unitary group associated to $F/F^+$. We assume $\overline{r}$ is semisimple and sufficiently generic at $v$. Using recent results of Breuil--Herzig--Hu--Morra--Schraen along with our previous work, we prove that certain admissible smooth $\overline{\mathbb{F}}_p$-representations of the $p$-adic unitary group $\textrm{U}_{1,1}(F^+_v)$ associated to $\overline{r}$ in spaces of mod $p$ automorphic forms have Gelfand--Kirillov dimension $[F^+_v:\mathbb{Q}_p]$., Comment: 66 pages. Comments welcome!

The numerical Monte-Carlo simulations of Cu-K$\alpha$ and Cu-K$\beta$ fluorescence lines induced by monoenergetic Am-241 radiation in copper have been presented. The simulations included modeling the K$\beta$/K$\alpha$ intensity ratios for various thicknesses of copper. The results obtained using the FLUKA code were compared to available experimental and theoretical values. A clear relationship was observed between the simulated K$\beta$/K$\alpha$ intensity ratios and the sample thickness: as the thickness increased, the K$\beta$/K$\alpha$ ratio also increased until it reached saturation.

The ED-XRF (Energy-Dispersive X-ray Fluorescence) measurements and the FLUKA simulations have been made to discuss the possibility of recognition of coating layer as well as to its thickness measurement. In this work the $I_{K\alpha}$(Cu)/$I_{K\alpha}$(Ag) intensity ratios as well as $I_{K\beta}$(Ag)/$I_{K\alpha}$(Ag) and $I_{K\beta}$(Cu)/$I_{K\alpha}$(Cu) for copper samples coated with various thickness of sputtered silver have been analyzed. The results show strong dependence of these factors with coating silver layer thickness. The measurements show the performance of this method in archaeometry. Since the use of non-destructive methods during tests on ancient silver artifacts may not supply to obtain reliable bulk results and should be considered applicable for only surface analyses, the measured intensity ratios can be applied as a tool to estimation of surface silver enrichment thickness., Comment: Accepted to publication to the Measurement journal

We report on the chemical structure and spin Hall magnetoresistance (SMR) in epitaxial $\alpha$-Fe$_2$O$_3$(hematite)(0001)/Pt(111) bilayers with hematite thicknesses of 6 nm and 15 nm grown by molecular beam epitaxy on a MgO(111) substrate. Unlike previous studies that involved Pt overlayers on hematite, the present hematite films were grown on a stable Pt buffer layer and displayed structural changes as a function of thickness. These structural differences (the presence of a ferrimagnetic phase in the thinner film) significantly affected the magnetotransport properties of the bilayers. We observed a sign change of the SMR from positive to negative when the thickness of hematite increased from 6 nm to 15 nm. For $\alpha$-Fe$_2$O$_3$(15 nm)/Pt, we demonstrated room-temperature switching of the N\'eel order with rectangular, nondecaying switching characteristics. Such structures open the way to extending magnetotransport studies to more complex systems with double asymmetric metal/hematite/Pt interfaces.

ESSnuSB is a design study for an experiment to measure the CP violation in the leptonic sector at the second neutrino oscillation maximum using a neutrino beam driven by the uniquely powerful ESS linear accelerator. The reduced impact of systematic errors on sensitivity at the second maximum allows for a very precise measurement of the CP violating parameter. This review describes the fundamental advantages of measurement at the 2nd maximum, the necessary upgrades to the ESS linac in order to produce a neutrino beam, the near and far detector complexes, the expected physics reach of the proposed ESSnuSB experiment, concluding with the near future developments aimed at the project realization., Comment: 19 pages, 12 figures; Final version after review by the Universe journal

Geological processes determine the distribution of resources such as critical minerals, water, and geothermal energy. However, direct observation of geology is often prevented by surface cover such as overburden or vegetation. In such cases, remote and in-situ surveys are frequently conducted to collect physical measurements of the earth indicative of the geology. Developing a geological segmentation based on these measurements is challenging since individual datasets can differ in properties (e.g. units, dynamic ranges, textures) and because the data does not uniquely constrain the geology. Further, as the number of datasets grows the information to constrain geology increases while simultaneously becoming harder to make sense of. Inspired by the concept of superpixels, we propose a deep-learning based approach to segment rasterized survey data into regions with similar characteristics. We demonstrate its use for semi-automated geoscientific mapping with datasets arising from independent sensors and with diverse properties. In addition, we introduce a new loss function for superpixels including a novel regularization parameter penalizing image segmentation with non-connected component superpixels. This improves integration of prior knowledge by allowing better control over the number of superpixels generated., Comment: 11 pages, 7 figures

The use of data to inform instruction has been linked to improved student outcomes, early identification of intervention needs, and teacher decision-making and efficacy. Additionally, data are used as a means of accountability within educational settings. However, little is known about data use practices among early grades teachers. The purpose of the current study is to describe the data use of PreK to third grade teachers and to investigate differences in data use and support across grade levels. Participants were 307 early childhood teachers in PreK and early elementary school. Analysis of survey data revealed, overall, most teachers across grade levels collected observational data and direct assessments and data were predominantly used to inform instruction and determine if students are ready to learn new skills. In general, teachers indicated that support for data use is available. Results also indicate significant variation in data types, use, and support across PreK to third grade. [This is the online first version of an article published in "Early Childhood Education Journal."]

We propose a general approach to analyse diagonal ordering patterns in bosonic lattice models with algebraically decaying density-density interactions on arbitrary lattices. The key idea is a systematic search for the energetically best order on all unit cells of the lattice up to a given extent. Using resummed couplings we evaluate the energy of the ordering patterns in the thermodynamic limit using finite unit cells. We apply the proposed approach to the atomic limit of the extended Bose-Hubbard model on the triangular lattice at fillings $f=1/2$ and $f=1$. We investigate the ground-state properties of the antiferromagnetic long-range Ising model on the triangular lattice and determine a six-fold degenerate plain-stripe phase to be the ground state for finite decay exponents. We also probe the classical limit of the Fendley-Sengupta-Sachdev model describing Rydberg atom arrays. We focus on arrangements where the atoms are placed on the sites or links of the Kagome lattice. \changed{Our method provides a general framework to treat cristalline structures resulting from long-range interactions., Comment: 35 pages, 11 figures

Presently under construction in Lund, Sweden, the European Spallation Source (ESS) will be the world's brightest neutron source. As such, it has the potential for a particle physics program with a unique reach and which is complementary to that available at other facilities. This paper describes proposed particle physics activities for the ESS. These encompass the exploitation of both the neutrons and neutrinos produced at the ESS for high precision (sensitivity) measurements (searches)., Comment: 121 pages, updated version after referee comments