Papers

The radioactive isotope $^{44}$Ti in Cassiopeia A has been used as a tracer of the innermost ejecta and explosion asymmetries in core-collapse supernova explosions. However, recent stellar-evolution models suggest substantial $^{44}$Ti may also be synthesized prior to explosion during oxygen-carbon (O-C) shell mergers, a process proposed for the Cas A progenitor. We investigate this pre-supernova contribution by combining NuSTAR measurements of the spatial and kinematic distribution of $^{44}$Ti with X-ray and infrared ejecta diagnostics. The low- and intermediate-velocity $^{44}$Ti components are more closely associated with O-layer tracers than with shocked Fe-rich material. If the $^{44}$Ti associated with the O-layer tracers was synthesized prior to core collapse, it could contribute up to $\sim7\times10^{-5}~M_\odot$, about half of the total. We find that this amount of $^{44}$Ti can be produced in O-C shell-merger models with ingestion rates and convective velocities higher than those in standard one-dimensional stellar-evolution calculations. Stable Fe-group abundance ratios measured with XRISM provide an additional constraint on the explosive contribution, as three-dimensional models with larger $^{44}$Ti yields tend to predict Ti/Fe and Mn/Cr ratios above the observed values. These results suggest that both pre-supernova shell-merger nucleosynthesis and explosive burning contribute to the observed $^{44}$Ti.

Understanding how optical orbital angular momentum (OAM) is transferred to matter requires treating recoil and translational motion alongside the internal electronic dynamics. We develop a center-of-mass-resolved theory of one-photon ionization of hydrogen by a monochromatic Laguerre–Gaussian beam and show that the Bessel-vortex photoelectron predicted in fixed-target models is a preparation-dependent limit. For a sharply defined atomic center-of-mass momentum, the recoil records the photon-cone azimuth, and tracing over it generally destroys the coherence required for a pure electron vortex. In the small-transverse-retardation regime, the optical OAM is transferred predominantly to the center-of-mass motion and hence, in the laboratory frame, to the proton. Finite-retardation corrections redistribute angular momentum between center-of-mass and relative motion, while an additional correlation contribution to the electron and proton angular momenta can be tuned through the spatial uncertainty of the atomic center of mass. These results reveal atomic recoil as a key element of OAM transfer in photoionization.

We study mass-conserving Markov jump processes on a square lattice, where masses hop with a preferred rotational sense, thus breaking both time-reversal and mirror symmetries. We consider closed systems with both periodic and open (reflecting) boundaries, the latter supporting a steady-state edge current. We show that odd diffusion, arising from the chiral transport, generically provides a mechanism for the emergence of scale-invariant two-point density correlations in nonequilibrium steady states even in the presence of lattice rotation symmetry – a mechanism that is qualitatively distinct from the well-known mechanism of anisotropic hopping. We exactly calculate the steady-state equal-time density-density correlations, which exhibit an algebraic decay, $C(\mathbf{r}) \sim |\mathbf{r}|^{-4}$ for $|\mathbf{r}| \gg 1$. This algebraic behavior results from the interplay between the off-diagonal components of the diffusion and mobility tensors, demonstrating that chiral transport alone can generate power-law correlations in isotropic driven systems. Remarkably, the structure factor in the zero-wavenumber limit and the amplitude of the power laws depend nontrivially on chirality. While increasing chirality initially suppresses large-scale density fluctuations, the fluctuations beyond a threshold odd-diffusion strength vary nonmonotonically with chirality and develop a cusp singularity.

Typically, vortices in wave fields are associated with amplitude zeros. In contrast, recently described high-intensity (Type II) wave vortices appear near amplitude poles and can exist only in disconnected space. We attempt to extend the concept of a Type II optical vortex (OV) to paraxial beam-like optical fields. It is shown that "true" Type II OV fields can exist only in a multiply connected three-dimensional space, where spatial "holes" impenetrable to the electromagnetic field are formed by purposefully created filamentary inclusions of material. However, the cross-section of a "true" Type II OV can be reproduced in a specific plane of ordinary "free" space, where the hole is designated by a region with zero amplitude. Methods for the practical creation of the discussed field structures are proposed, including methods using programmable light modulators and computer-synthesized holograms. The results of computer simulations demonstrate reasonable agreement with experimental data.

In this study, quantum spin pumping in an antiferromagnetic chain driven by time-dependent potential is investigated. The aim is to explore the possibility of generating and controlling spin currents in the absence of external bias and to examine the role of exchange field and periodic driving in the separation of spin-up and spin-down currents. The system is described using a tight-binding model, and spin-resolved currents are calculated employing the Keldysh non-equilibrium Green's function formalism. Two time-dependent potentials with a specific phase difference are applied to the two ends of the chain, while the chemical potentials of both electrodes are set equal. The results demonstrate that in the adiabatic regime (low frequencies), the response of the two spin channels is nearly identical. However, as the driving frequency increases and the system enters the nonadiabatic regime, absorption and emission processes of energy quanta become activated, leading to significant differences between spin-up and spin-down currents. The pumped current exhibits strong dependence on the chemical potential, allowing for the control of both magnitude and direction of the spin current through its adjustment. With increasing frequency, the spin current enhances, and parameters can be tuned such that the charge current nearly vanishes while a considerable spin current persists. This finding indicates the feasibility of achieving nearly pure spin pumping without net charge transfer in the antiferromagnetic chain. The results provide a promising perspective for designing spin-pumping devices based on antiferromagnetic systems.

We have observed that Hadamard matrices whether real or complex lead to a dense output of identical probabilities for any given single input state. Complex Hadamard matrices have unusual orders and introduce phase which prove useful when controlled phase transformation gates are used. By taking a superposed combinations of input states, we discovered that the Hadamards generate non-uniform probabilities which is practically significant towards amplitude amplification without the need for manual parameterization like Grover's operator~\cite{grover1996}. A variety of graph theoretic properties are applied to TSS graphs and their trends were explored. Additionally, graphs turn out to be nearly isomorphic for the same set of input states which has potential applications for developing Quantum Algorithms. Keywords: Quantum Algorithms, Hadamard Matrices, Unitary Matrix Approach, Topological Structure of Superpositions (TSS), Graph Theory

(Abridged) The composition of the inner regions of protoplanetary disks is known to change with time due to the delivery of icy grains. Cold H$_2$O emission seen with JWST-MIRI is often hypothesized to be a tracer of this pebble drift. However, it is unclear to what extent processes such as photodissociation or the co-delivery of dust may impede such detections. We aim to obtain an improved, 2D view of transport in disks, to better understand how these processes can be traced by H$_2$O emission as seen with JWST-MIRI. We combine the 1D transport code DiscEvolution with the 2D thermochemical code DALI to create several grids of models in which the gas-phase abundances, dust properties, or both are varied according to the transport model. We consider scenarios with and without a traffic jam inside the H$_2$O snowline. The transport of both gas and dust leads to significant temperature changes within the disk, which strongly influence line fluxes and ratios. When a traffic jam is present, the delivery of H$_2$O can proceed unnoticed due to the co-delivery of dust. In addition, the relative strength of cold H$_2$O lines is not found to be sensitive to this delivery of gas-phase H$_2$O. Instead, the cold H$_2$O lines can be greatly enhanced by the delivery of only dust to the inner disk when a traffic jam is present, and one can create a spectrum with strong cold H$_2$O emission solely through the delivery of dust rather than H$_2$O. Recent work has used the 1500/6000 K H$_2$O line ratio as a proxy to determine the pebble mass flux crossing the H$_2$O snowline, but we find that this line ratio is rather sensitive to the temperature and dust distribution of the disk, and is often influenced not only by the cold H$_2$O mass, but also by the hot H$_2$O mass. This introduces complexities and trends as a function of time that do not match the true evolution of the pebble flux.

Born effective charge (BEC) tensors link atomic displacements to polarization, thereby connecting lattice vibrations with dielectric response and infrared activity. We present ZStar, an open-source Python toolkit that automates calculations of polarization, BEC, phonons, static and frequency-dependent dielectric response, and infrared and Raman spectra. ZStar supports bulk crystals, two-dimensional materials, one-dimensional structures, and molecules through an integrated workflow for input preparation, execution, and response analysis. Berry-phase polarization and real-space dipoles describe responses along periodic and open directions, respectively. Its unified, symmetry-adapted finite-displacement framework jointly determines BEC and zone-center force constants from the same calculations, improving computational efficiency while preserving numerical accuracy. Strain-response calculations further provide proper piezoelectric coefficients and their internal-relaxation contributions for bulk crystals. In the ABACUS+PYATB route, electronic Hamiltonian data are reused to obtain Raman response without additional self-consistent calculations. Native response implementations from VASP and CP2K are also integrated. Matched infrared/Raman benchmarks against the implemented separate workflows achieve speedups of up to 8.4. An accompanying agent skill provides an agent-friendly interface for workflow integration. ZStar therefore offers an efficient and automated route for exploring polarization, BEC, dielectric and piezoelectric responses, and vibrational spectra across different material dimensionalities.

Ferroelectric semiconductors are promising for multifunctional electronics, yet their typically low carrier mobilities remain a major limitation. Using first-principles phonon-limited transport calculations for monolayer In$_2$Se$_3$, we show that this limitation depends critically on the microscopic origin of ferroelectricity. In displacive $\beta'$-In$_2$Se$_3$, low-frequency ferroelectric modes dominate carrier scattering, with additional contributions from longitudinal-optical (LO) phonons, limiting the room-temperature electron mobility to a few cm$^2$/(V s). By contrast, in fractional-quantum ferroelectric $\alpha$-In$_2$Se$_3$, ferroelectric-mode scattering is absent because polarization arises from discrete lattice-scale atomic displacements rather than soft-mode condensation. Transport is therefore dominated by LO phonons, yielding a room-temperature mobility above 70 cm$^2$/(V s). Carrier doping further screens long-range electron-LO-phonon interactions and raises the mobility beyond 300 cm$^2$/(V s) at experimentally accessible densities. These results establish that fractional-quantum ferroelectricity can decouple robust polarization from strong intrinsic carrier scattering, offering a route toward high-mobility ferroelectric semiconductors.

This paper starts a series of works devoted to an in-depth study of luminous blue variable AF And in the M31 galaxy. Here we present the results of non-LTE modelling of the star in a hot state with CMFGEN code. In addition to the $\beta$-velocity law, widely used in the analysis of stellar atmospheres, we used a velocity distribution obtained from the balance of radial forces in the wind, including centrifugal forces for several models. Such a dynamically consistent approach reduces the parameter space during modelling and, in addition, allows us to estimate the current stellar mass whose inner hydrostatic layers are obscured by a dense wind that contaminates the absorption profiles. Based on our modelling we estimate the parameters of AF And as follows: luminosity $L \approx 6.5\times10^5~\text{L}_\odot$, mass loss rate $\dot{M}$ $\approx 3\times10^{-5}~\text{M}_\odot~\text{yr}^{-1}$, terminal velocity $v_\infty \approx 300~\text{km s}^{-1}$ and effective temperature $T_{\rm eff} \approx 17~\text{kK}$. modelling of the hot state of AF And is of particular interest due to the possibility to place constraints on the ratio of hydrogen and helium abundances for further use in constructing models of the cold state of this star. We conclude that the current hydrogen mass fraction in the wind lies in the range from $20$ to $30$ per cent. Self-consistent modelling gives the current mass $M_*$ estimation in the range $15.6 - 17.7~\text{M}_\odot$. By employing evolutionary tracks, we were able to estimate the initial stellar mass as $M_{*,~init} \approx 50~\text{M}_\odot$.

Glueballs are colour-singlet bound states built from gluons alone. They are an unavoidable consequence of the non-Abelian structure of Quantum Chromodynamics (QCD), and, in the pure Yang–Mills limit, they are the only physical excitations of the theory. The present article reviews what is known about them. After establishing which spin, parity and charge-conjugation quantum numbers two- and three-gluon states can carry, the pure-gauge spectrum is surveyed. Each of the main theoretical approaches and their respective conclusions are briefly presented. They include lattice QCD, constituent-gluon and Coulomb-gauge models, functional Dyson–Schwinger and Bethe–Salpeter equations, holographic models, and QCD sum rules. Particular attention is paid to the scale-setting ambiguity that limits how precisely a quenched glueball mass can be converted into physical units. The discussion then turns to full QCD. After discussing the meaning of a glueball assignment in this context, unquenching effects and questions related to glueball–$q\bar{q}$ mixing are addressed. The large-$N_c$ counting that underpins the mixing picture, as well as mass-matrix and effective-Lagrangian treatments of mixing are presented. The selection rules and dynamical mechanisms that shape glueball decays are also discussed. The gluon-rich production mechanisms used experimentally are finally reviewed. The candidates are assessed sector by sector: $f_0(1370)/f_0(1500)/f_0(1710)$ and the competing interpretations of the scalar sector, $\eta(1405)/\eta(1475)$ and $X(2370)$ in the pseudoscalar sector, the crowded tensor region, and the essentially unexplored $C=-1$ sector and its connection to the Odderon. Outlooks on the programmes that could help in validating some of these candidates or identifying others are reviewed as a conclusion.

SpectraFit XPS is a free web application for the analysis of X-ray photoelectron spectroscopy (XPS) data that runs entirely in the browser, with no installation and no server-side processing: spectra never leave the user's computer. It combines an interactive Levenberg–Marquardt fitting engine with true Voigt, Doniach–Šunjić, and summed Gaussian–Lorentzian line shapes; Shirley (static and dynamic), linear, and Tougaard (two- and four-parameter) backgrounds; spin–orbit doublet generation; and expression-based inter-peak constraints. Quantitative analysis supports ten relative-sensitivity-factor sets, several kinetic-energy correction schemes including TPP-2M inelastic mean free paths, angular correction, and atomic and weight percentages, with the underlying database and algorithms adapted from the open-source KherveFitting project. The application reads and writes ISO~14976 (VAMAS) files—including multi-region and depth-profile data and load-time transmission-function correction—and imports common vendor and spreadsheet formats. A publication plotter exports journal-ready SVG/PNG figures. The quantification pipeline reproduces KherveFitting reference values exactly in a 30-case regression suite, part of an automated test set of 100 tests. The application, an illustrated bilingual user guide, and a synthetic demonstration dataset are freely available at https://spectrafit-xps.web.app/.

Electrical noise measurement, especially shot noise, which arises from the discreteness of charge, is an indispensable tool in quantum transport for probing the nature of charge carriers beyond simple conductance measurements. Diffusive conductors share a universal shot noise reduction of 1/3, a result obtained independently from quantum scattering theory, semi-classical kinetics, or by classical exclusion processes8. Until now, however, experimental tests of this universality have been limited to cryogenic conditions, leaving its origin incompletely understood. Here we show that ferrocene redox cycling in a microfluidic gap is a room temperature realization of this universality. We derive the full counting statistics of diffusing single-electron molecular shuttles and verify the predicted current noise experimentally, showing that the universal 1/3 shot noise suppression is recovered in the diffusion-limited regime. Our result identifies diffusion and sequential charge transfer as sufficient ingredients for this universal noise reduction, rather than quantum coherence, fermionic statistics or cryogenic conditions. We anticipate that this study will establish electrochemical microfluidics as a room-temperature platform for mesoscopic counting statistics and bring noise-based probes to molecular transport and reaction kinetics. Furthermore, this liquid-based quantum-inspired study will provide a novel insight on the yet to be understood links between quantum and biology.

We perform population synthesis modeling of neutron star binary systems containing a low-mass main-sequence companion underfilling its Roche lobe. About $10^5$ such systems are expected to exist in the Milky Way. In the majority of such systems, NSs are expected to start accreting the stellar wind matter within a few Gyr, resulting in the appearance of a dim X-ray source. The exact value of this fraction mainly depends on the efficiency of the propeller spin-down, properties of the stellar wind, and common envelope efficiency. Mostly, NSs in such systems are formed in electron capture supernovae. Thus, they obtain a low natal kick. Due to this, the center-of-mass velocities of such binaries are low, too. Only in the case of high common envelope efficiency ($\alpha_\mathrm{CE}\gtrsim 3$), a few tens of long-lived high-velocity binaries can be produced in core-collapse supernovae.

We investigate the quantum Mpemba effect, whereby a system initially farther from equilibrium relaxes faster than one initially closer to equilibrium, emerging in a quantum harmonic oscillator linearly coupled to a bosonic environment. Starting from factorized thermal states at different temperatures, we derive exact analytical criteria for the occurrence of the quantum Mpemba effect valid also beyond the typically considered weak-coupling and Markovian approximations. Most importantly, we show that the effect is enabled by the initial-slip dynamics generated by the sudden switch-on of the system-bath interaction. Neglecting this contribution completely suppresses the anomalous relaxation, identifying transient system-bath correlations as the key ingredient underlying the quantum Mpemba effect.

Altermagnetism has recently emerged as a distinct magnetic paradigm, yet the exploration of topological spin textures within two-dimensional (2D) altermagnets remains limited. Using first-principles calculations and atomistic spin simulations, we investigate monolayer $\mathrm{Cr_2X_2}$ and Janus monolayer $\mathrm{Cr_2XY}$ altermagnets ($\mathrm{X, Y}=\mathrm{O, S, Se, Te}$, and $\mathrm{X \neq Y}$). Both systems exhibit strong intrinsic exchange frustration arising from competition between nearest-neighbor and further-neighbor exchange interactions. In Janus $\mathrm{Cr_2XY}$, breaking the out-of-plane mirror symmetry additionally activates a substantial in-plane Dzyaloshinskii-Moriya interaction (DMI), mediated by the strong spin-orbit coupling of heavy chalcogen ligands. The interplay between exchange frustration and DMI gives rise to distinct frustration- and DMI-dominated regimes, while magnetic anisotropy determines the preferred spin orientation, leading to a diverse range of non-collinear states. Systematic phase-space scans and geodesic nudged elastic band (GNEB) calculations reveal two distinct mechanisms governing this interplay: a synergistic effect, in which frustration lowers the critical DMI for the onset of non-collinear states, and a competitive effect, in which frustration favors high-topological-charge states while DMI favors low-charge states. Our results establish a general framework for understanding the interplay between frustration and DMI and guiding the design of topological spin textures in two-dimensional altermagnets.

In van der Waals(vdW) layered materials, interlayer shift and twist have enabled the control of material properties through polytype and moire engineering. Various approaches, including bottom-up synthesis and manual layer-by-layer stacking, have been utilized to engineer targeted stacking configurations. However, the interplay between interlayer shift and twist, as well as reliable mechanisms for fine-tuning these parameters, remains largely unexplored. Here, we report a previously unrecognized twisting mechanism arising from preferred tilted stacking and twinning in vdW crystals. Electron diffraction and atomic-resolution scanning transmission electron microscopy(STEM) imaging reveal that the lattice planes of group-IV chalcogenide GeSe_{2-x}Te_x rotate continuously along the nanowire growth axis, with twist rates depending systematically on nanowire radius. Atomic-scale imaging further identifies a continuous rotational twin boundary extending along the central region of the nanowire. First-principles calculations and structural relaxation simulations confirm that the twisting deformation originates from energetic competition between the preferred interlayer stacking registry and the strain cost imposed by rotational twinning. These findings establish rotational twinning as an intrinsic route to spontaneous twist formation and provide a design principle for realizing twist-engineered vdW crystals with compatible crystal symmetries and stacking motifs.

We investigate the exclusive semileptonic and nonleptonic $\Lambda_{b} \to \Lambda_{c}(p)$ decays within the Standard Model by using the light-front quark model. To determine the behavior of the $\Lambda_{b} \to \Lambda_{c}(p)$ transition form factors, we employ the Bethe-Salpeter formalism in the timelike region, effectively accounting for both valence and nonvalence contributions. Using these form factors, including nonvalence contributions, we obtain branching fractions of $\Lambda_b \to \Lambda_c\,\ell\,\bar{\nu}_{\ell}$, $\Lambda_b \to \Lambda_c\,\tau\,\bar{\nu}_{\tau}$, $\Lambda_b \to p\,\ell\,\bar{\nu}_{\ell}$ and $\Lambda_b \to p\,\tau\,\bar{\nu}_{\tau}$~($\ell=e$ or $\mu$) are found to be around $5.39\%$, $1.41\%$, $3.33\times 10^{-4}$ and $2.08\times 10^{-4}$, respectively, which are consistent with the experimental measurements. The ratios of $R^{\ell\tau}(\Lambda_{c})=\frac{{\cal B}({\Lambda_b}\to {\Lambda_c}\,\tau\,\bar{\nu}_\tau)} {{\cal B}({\Lambda_b}\to {\Lambda_c}\,\ell\,\bar{\nu}_l)}$ and $R^{\ell\tau}(p)=\frac{{\cal B}({\Lambda_b}\to p\,\tau\,\bar{\nu}_\tau)} {{\cal B}({\Lambda_b}\to p\,\ell\,\bar{\nu}_l)}$, are given by $0.261^{+0.097}_{-0.117}$ and $0.624^{+0.119}_{-0.129}$, respectively. The forward-backward asymmetries in the above semilepton decays are also examined. Our results indicate that, within the light-front framework, the nonvalence contributions to the asymmetries are negligible compared to the $\beta$-induced uncertainties. In addition, we calculate the branching ratios for the nonleptonic decays of $\Lambda_{b}\to \Lambda_{c}(p)\,M$ with $M$ being the pseudo scalar and vector mesons with the results found to be consistent with the current experimental data.

We investigate the sensitivity of future muon colliders to the anomalous magnetic moment of the tau neutrino within a model-independent effective field theory framework. The analysis is performed through the subprocess $\mu^{-}\gamma \rightarrow \mu^{-}\nu\bar{\nu}$ where the initial-state photon is described using the Equivalent Photon Approximation. Signal and background events are generated with MadGraph5$\_$aMC$@$NLO, followed by parton showering and hadronization with PYTHIA8. Detector effects are simulated using DELPHES3, while the event reconstruction and analysis are carried out via the MadAnalysis5 framework. Optimized kinematic selection criteria are determined for center-of-mass energies of 3, 10 and 30 TeV muon colliders. The expected sensitivities are evaluated using the Asimov significance method. The best sensitivity is obtained for the 30 TeV muon collider option, where the anomalous magnetic moment of the tau neutrino can be probed down to $\mu_{\tau\tau}=5.21\times10^{-8}\,\mu_B$ at the 5$\sigma$ significance level assuming a 1% systematic uncertainty. Our sensitivity bounds improve the current direct experimental limit reported by the DONUT Collaboration up to one order of magnitude and demonstrate the strong potential of future muon colliders for probing neutrino electromagnetic interactions.

Let $d\ge1$ and $V\in C(\mathbb{T}^d;\mathbb{C})$. We prove that the Bloch variety of $-\Delta+V$ is irreducible modulo periodicity. The proof combines holomorphic continuation of spectral band functions with integer translations of quasimomentum. Using analytic geometry and perturbation estimates along imaginary rays, we show that, after suitable integer translations, all irreducible components contain the same holomorphic spectral branch.

The paper presents a further development of the method G. Gaigalas, P. Rynkun, L. Kitovienė, Second-Order of Rayleigh-Schrödinger Perturbation Theory for the Grasp2018 Package: Core-Valence Correlations, Lithuanian Journal of Physics, 64, No. 1, 20-39 (2024) (https://doi.org/10.3952/physics.2024.64.1.3), based on a combination of the relativistic configuration interaction method and on the stationary second-order Rayleigh-Schrödinger many-body perturbation theory in an irreducible tensorial form. In this extension the perturbation theory accounts for both electron core-valence and core correlations when an atom or ion has any number of valence electrons meanwhile relativistic configuration interaction accounts for the rest of correlations. This allows a significant reduction of the space of the configuration state function for complex atoms and ions. We also demonstrate how this method works for energy structure calculation of Fe XV ion.

Multiferroics combining magnetic and polar orders offer opportunities for optical control of spin and electric degrees of freedom. Here, using symmetry analysis and Floquet theory, we establish Floquet spin-antiferroelectricity coexisting with unconventional magnetism in periodically driven collinear antiferromagnets, qualifying it as an unconventional multiferroic. This driven phase supports compensated, spin-resolved in-plane electric polarizations perpendicular to the vertical rotation axis, which are strictly forbidden by crystalline symmetry in equilibrium. Using a tight-binding model, we elucidate how light polarization controls the emergence of polar order and spin responses. Moreover, first-principles-based Floquet calculations predict its realization in monolayer $\text{MnPS}_3$, identifying a realistic two-dimensional antiferromagnetic platform. These findings establish a nonequilibrium route to spin-antiferroelectricity beyond equilibrium symmetry constraints and connect Floquet engineering, unconventional magnetism, and multiferroicity through optical control of spin and polar degrees of freedom.

We introduce the hadron-anchored energy correlator (HAEC), a jet-restricted realization of the fragmentation energy correlator and the semi-inclusive energy correlator frameworks, and apply it to heavy-flavor-tagged jets in hadron collisions. Using Pythia~8 simulations of ${\rm D}^0$- and $\Lambda_c^+$-tagged jets, we find a pronounced, localized suppression of energy flow around the $\Lambda_c^+$ relative to the ${\rm D}^0$, followed by a sharp transition scaling as $\theta_0\propto1/p_{\rm T}^{\rm jet}$ with little tune dependence. The conventional jet-axis radial profile shows qualitatively different color-reconnection dependence, suggesting reduced sensitivity of HAEC to jet-axis effects. A beauty-sector study can distinguish a heavy-quark-mass origin from a local fragmentation-vertex origin.

Altermagnetism combines vanishing net magnetization with momentum-dependent spin splitting. While altermagnetic signatures have been identified in metal-organic frameworks (MOFs), non-invasive reversible control remains challenging. Here we report a route to electric-field-switchable altermagnetism in a flexible d0-MOF, in which polar substituents couple the external field to ligand rotation. In the planar ground state, pz orbitals mediate 180-degree ligand-metal-ligand superexchange (J2), stabilizing antiferromagnetic order. Rotating ligands out of plane activates px/py orbitals, enhances 90-degree pathways (J1), and reverses J1/J2 competition. The antiferromagnetic-to-altermagnetic crossover occurs at approx. 34 degrees, with spin splitting of 84 meV at 90 degrees. The 90-degree altermagnetic state is switched on by the electric field and switched off upon field removal, as the constrained-rotation landscape decreases monotonically back toward 0 degrees, enabling barrierless relaxation to the antiferromagnetic state and reversible on/off operation. Ab initio molecular dynamics at 300 K shows thermal fluctuations alone cannot synchronize ligand rotation. Polar substituents provide the required coupling for electric-field control; for fluorinated substituents, the critical field is approx. 0.22 V/Angstrom, comparable to field-effect devices. This work establishes ligand p orbitals, rather than transition-metal d orbitals, as the origin of altermagnetic order and shows that polar substituents enable electric-field control for organic spintronics.

We prove an asymptotic expansion of a weighted heat trace of the Dirichlet Laplacian on a bounded Lipschitz domain. The weight is given by a power of the distance to the boundary times a bounded function that is continuous near the boundary. Depending on the exponent of the weight, we obtain one-term or two-term asymptotics. We present two applications, namely a version of one-term asymptotics of weighted Riesz means for arbitrary orders, as well as convergence results for a family of measures that describes localization of Laplace eigenfunctions.

Entangling distant quantum sensors is a key application of future quantum networks, allowing for the estimation of global functions of local parameters, with precision that is not possible with stand-alone, individual, quantum sensors. However, with this advantage comes the risk of information leakage over the network via possible malicious parties. It is often particularly important that local parameters remain unknown and that only the global function is shared across the network. Recently, the notion of privacy has been introduced in this context, which ensures that only the agreed function of parameters is shared over the network, even when malicious parties control the network itself, whilst maintaining the estimation advantage. In this work, we introduce a noise-robust protocol for private quantum networked sensing, which we realise using a high-fidelity Greenberger-Horne-Zeilinger (GHZ) state source. We further run a comparative analysis and simulate attacks using three different quantum states, a four-qubit GHZ state, two Bell pairs, and a fully separable state. Our results highlight the clear advantage of GHZ states in maintaining high precision, accuracy, and privacy for the distributed estimation task.

Baryonic feedback in hydrodynamical simulations is typically invoked to alleviate the core–cusp problem in dwarf galaxies. Yet baryonic processes also induce adiabatic contraction of dark matter, producing overly steep density profiles and excessively high dark matter fractions in the inner regions of massive galaxies. The dark matter distribution of galaxies across a wide stellar-mass range is therefore a critical test for such simulations, but a comprehensive benchmark has remained absent. Here, we consistently measure the dark matter distribution from galaxy centres out to radii of 20–50 kpc for 136 nearby galaxies that together span the local mass–size relation over the stellar mass interval $10^9$–$10^{11.5}\,M_{\odot}$. We identify central regions with lower dark matter densities relative to $\Lambda$CDM simulation expectations—whose extent grows from about 10 kpc to $>50$ kpc as stellar mass increases from $10^{10} M_{\odot}$ to $10^{11.5} M_{\odot}$. Although their physical origin remains unclear, these low–dark matter regions are clearly indicated by the data. Our results provide an important observational benchmark for future hydrodynamical simulations that explore alternative dark matter models and feedback processes.

The effectiveness of luminescence thermometry, which exploits temperature-induced changes in the spectroscopic properties of phosphor materials for temperature sensing, has been extensively demonstrated. However, from a practical perspective, monitoring temperature-induced variations in the color of the emitted light offers a considerably more straightforward and user-friendly alternative to conventional spectral analysis. In this context, establishing a clear relationship between the thermal evolution of the emission color and the structure of the phosphor is essential for the rational design of visual luminescence thermometers. In this work, we investigate the correlation between the temperature-dependent emission color and the structural characteristics of Tb3+, Eu3+-co-doped metal-organic frameworks (MOFs), with particular emphasis on their potential for filter-free, camera-based thermal sensing. The obtained results demonstrate that, within the investigated series of materials, decreasing the interionic distance between Eu3+ and Tb3+ ions increases the probability of energy transfer and consequently enhances the thermal sensitivity of the camera-based readout derived from the ratio of luminescence intensities recorded in the blue and red channels. These findings establish a direct relationship between the structural characteristics of the luminescent material, the underlying energy-transfer processes, and its thermometric performance. More broadly, this study provides a foundation for the rational design of visual luminescence thermometers with predefined sensing characteristics, opening a pathway toward structure-guided optimization of filter-free, camera-based thermal sensing platforms.

We present a feasibility study demonstrating how recent advances in quantum-sensing technologies can facilitate stringent comparisons between theoretical predictions and experimental measurements of contact-free transitions in muonic atoms. Such comparisons can probe previously unexplored regions of the parameter space governing spin-independent muon-proton interactions and disentangle the extraction of fundamental constants from searches for physics beyond the Standard Model.

We refine Gavinsky's framework (arXiv:2608.18784) for exponential separations between quantum and randomized communication complexity of total functions and obtain larger separations: polylogarithmic quantum communication versus $\tilde\Omega(\sqrt n)$ randomized communication with two quantum messages, and versus $\Omega(n^{1-\varepsilon})$ for every fixed $0<\varepsilon<1$ with more quantum messages.