Soft Condensed Matter
Loading history and window geometry bound compact-state slip ranking during granular shear startup
Ruixin Zhou and Boliang Yu
Granular slip
forecasting can conflate material state, loading progress, and the geometry of event-centered sampling. We separated these contributions in slowly sheared two-dimensional frictional disks using a compact neural score of stress, pressure, coordination, non-affine motion, and force-network observables. The model was developed on 36 trajectories and frozen efore testing on 18 new trajectories under two nested stress-drop definitions. Inspection of held-out results revealed post-event sampling asymmetry; recovery-aware analyses are therefore descriptive. With trajectories weighted equally, the compact score ranked near-slip windows above both prevalence and within-trajectory circular-phase controls under both definitions (representative average precision 0.310 versus prevalence 0.173; phase-null upper bound 0.257). Loading-history coordinates ranked more strongly, reaching 0.534 for causal elapsed strain. The recovery-aware rule retained 78.4% of activity-gated events and preferentially selected longer preceding intervals; ranking by time since the previous catalogued event remained compatible with a count-conditioned geometry null. Compact observables thus contain temporally aligned slip information, but stronger loading-history baselines and window-geometry sensitivity bound that evidence. These startup data do not isolate a state-specific short-horizon precursor beyond loading history or support a renewal interpretation of elapsed-strain ranking.
Read the full abstract ▾
Chemical Physics
Strictly Localized Molecular Orbitals: Non-Orthogonal Local Orbitals Built with Chemical Intuition
Jeffrey Keyes and Carlos Jimenez-Hoyos
We propose the use of an a priori localization method based on separating the molecule into fragments to generate a wavefunction suitable for post Hartree-Fock methods. A quasi-Newton approach utilizing Thouless rotation is developed to optimize the strictly localized molecular orbitals(sLMO). We discuss the properties of the sLMO-HF wavefunction and compare it to the tail deleted a posteriori localization methods that are usually done in preparation of post Hartree-Fock methods. We then discuss the effects of choosing different fragmentation patterns and basis sets.
Read the full abstract ▾
Quantum Physics
Exact Posterior Prediction from Product Haar Measurements and a Randomized-Mesh Maximum-Likelihood Bridge
Naqueeb Ahmad Warsi, Ayanava Dasgupta and Masahito Hayashi
We study prediction of one unmeasured copy of an unknown finite-dimensional pure
quantum state after independently measuring the observed copies with the one-copy Haar POVM. For the resulting fixed separable observation, the Bayes predictive state under
quantum relative-
entropy loss is the full-rank posterior mean. We evaluate it exactly through permanents of minors of the outcome Gram
matrix, prove positivity and normalization of the permanent representation, and establish minimaxity among decision rules based on these fixed outcomes. Using
Hilbert–Schmidt projection of the posterior mean and an exactly analyzed linear-inversion competitor, we prove a finite-sample posterior-purity bound and an explicit relative-
entropy guarantee with sample count $O((d^2/\epsilon)\log(d/\epsilon))$. Using the exact collective
benchmarks proved in a companion paper, we also obtain
entropy and posterior-purity comparisons. To connect the fine product data to a regular ray-valued experiment without assuming deterministic finite-sample uniqueness, we draw one random orientation for a finite projective mesh, retain it for the entire sample, and apply a selected finite-alphabet MLE in the resulting reference experiment. A nested recovering mesh uniformly recovers the fine Fisher information. Consequently every sufficiently fine fixed mesh gives a regular finite-alphabet model. Its selected MLE has Haar-averaged inverse-Fisher coefficient $\overline a_k$, and refining the mesh after the fixed-mesh large-sample limit makes $\overline a_k$ approach $d-1$. This yields epsilon-optimal leading relative-
entropy and posterior-overlap bounds for the fine posterior and the sharper fixed-dimensional asymptotic scale $(d/\epsilon)\log(d/\epsilon)$. The latter is not asserted as a uniform finite-sample guarantee. No deterministic finite-sample MLE uniqueness or triangular mesh schedule is used.
Read the full abstract ▾
Quantum Physics · Cross-listed from math.PR
Local Anticoncentration for Gaussian Boson Sampling via Conditional Wishart Geometry
Hongru Zhao
Local anticoncentration controls the conversion of additive output probability estimates to relative estimates in Gaussian
boson sampling. We prove a center-uniform quadratic small-ball bound for hafnians of complex Gaussian transpose Gram
matrices for $2n$ selected modes, with an explicit finite coefficient that is
polynomial when the number of Gaussian rows is at least of order $n^2/\log n$. Letting the Gaussian row count tend to infinity yields anticoncentration for the independent complex symmetric Gaussian ensemble. For the transpose Gram hafnian bound, the proof compresses dependent hafnian cofactors by
Fourier interpolation and controls their self-coupled variance through a conditional Wishart identity that preserves the transpose Gram coordinate. Independent perturbations satisfy related bounds, and a positive mixture density shows that the local quadratic power is exact. Together with the uniform hiding
theorem in the companion paper, the result gives local anticoncentration for finite Haar interferometers.
Read the full abstract ▾
Strongly Correlated Electrons
Emergence of electronic modes and triplet pairing from spin-1 antiferromagnetic insulators in the Kanamori-Hubbard model
Masanori Kohno
The electronic band structures of conventional band
insulators generally remain unchanged under doping via chemical-potential shifts or increasing temperature. However, in Mott and Kondo
insulators described by models such as the Hubbard and Kondo
lattice models, distinct electronic modes with momentum-shifted
magnetic dispersion relations have been shown to emerge from band edges into the gap. Here, by investigating the two-orbital Kanamori-Hubbard model, this study elucidates how and why the band structures of
spin-1
antiferromagnetic insulators change with doping and temperature, revealing emergent spectral features characteristic of orbitally degenerate systems. The nature of the emergent electronic modes is clarified using weak-hopping effective theory, selection-rule analysis, and numerical calculations. In a typical parameter regime, the doping-induced modes in each orbital reflect distinct types of
spin modes, while the temperature-induced modes primarily reflect the low-energy
spin mode in both orbitals; in both cases, the emergent modes exhibit momentum-shifted
spin-mode dispersion relations. The momentum regimes of these emergent modes can differ between orbitals if signs of the hopping parameters differ. For small inter-orbital repulsion, onsite
spin-triplet pairs can form after doping, leading to a pair-breaking gap, while the temperature-induced electronic modes continue to reflect the low-energy
spin mode without a pair-breaking gap. Moreover, the emergence and characteristics of electronic modes in nonequilibrium states by
spin or charge perturbations are elucidated. These findings provide a comprehensive understanding of how the interplay among the
spin, charge, and orbital degrees of freedom in large-
spin antiferromagnetic insulators leads to emergent electronic modes, opening avenues for exploring unconventional
quantum phenomena in strongly correlated systems.
Read the full abstract ▾
Instrumentation and Detectors
Real-Time SiPM Pulse Deconvolution for a High-granularity Dual-readout Calorimeter with Neutral Networks
Spencer Allen, Matteo Cremonesi, Jordan Damgov et al. (+6 more)
The High-Granularity Dual-Readout Calorimeter (HG-DREAM) designed for FCC-ee aims to achieve unprecedented energy resolution through fine three-dimensional shower imaging, simultaneous measurement of Cherenkov and scintillation signals, and machine learning capabilities. A key enabling technology is longitudinal
segmentation via timing measurements, where multiple energy deposits along optical fibers are distinguished by the arrival times of Cherenkov
photons. We present quantized one-dimensional convolutional neural networks that predict pulse locations directly from 80-sample, 16 ns waveforms digitized at 200 ps, and evaluate their implementation in front-end electronics. Three architectures, a compact baseline and two variants using dilation and stride to reach the $\sim$ 20-sample receptive field set by the SiPM pulse width, achieve ROC AUC above 0.95 with four to eight filters per layer. Fixed-point quantization to a $<$16,8$>$ baseline costs less than $10^{-3}$ in AUC relative to the floating-point reference. Applied to pairwise deposits, the smallest model separates two pulses with better than 95% probability at longitudinal separations of 20 cm and above. Synthesized at 400 MHz, this model uses 9663 LUT on a Xilinx XCVU13P FPGA and occupies $\sim$ 18500 $\mu$$m^2$ in TSMC 28 nm CMOS with reconfigurable weights. Assuming a triggered readout architecture for FCC-ee, the $\sim$ 500 kHz Z-pole trigger rate will be the most stringent throughput requirement across all FCC-ee operating modes. The ASIC implementation of the model sustains 4.8 MHz, exceeding the 0.5 MHz requirement by an order of magnitude, while the reconfigurable-weight FPGA implementation fails to do so. Sustaining the 40 MHz FCC-ee Z-pole bunch-crossing frequency in the triggerless architecture is not feasible with the models developed and the hardware targeted in this work.
Read the full abstract ▾
All authors Spencer Allen, Matteo Cremonesi, Jordan Damgov, Erdem Yigit Ertorer, Janna Goodman, Giuseppe Di Guglielmo, James Hirschauer, Shuichi Kunori, Peter Meiring
Materials Science
Efficient spectral Galerkin framework for nonlinear transient heat transfer in finite domains
Théo Andrieux, Andreas Ntinos and Manas V. Upadhyay
Accurately modelling the temporal
evolution of heterogeneous temperature fields requires resolving strong nonlinearities in the heat equation arising from temperature-dependent thermophysical properties, latent heats of transformation and any local heat sources/sinks. In this work, we present a spectral Galerkin (SG) framework to solve the fully nonlinear transient heat equation in finite domains to attain the accuracy of high-fidelity finite element (FE) simulations at considerably lower computational cost. The heat equation is reformulated into a linear reference problem with constant thermophysical properties and residual forcing terms. Solving the reference problem provides a complete three-dimensional orthonormal trigonometric basis, whose Galerkin projection reduces the heat equation to a set of modal ordinary differential equations (ODEs) in time; the reference operator is diagonal in the modal basis, and results in independent modal updates for a fixed nonlinear forcing. These ODEs can be integrated using exponential time differencing and iteratively corrected for nonlinearities. The SG method eliminates the global solve required by FE methods, and its use of structured grids allows efficient GPU parallelization. Applied to rapid
laser-metal interactions, the SG solver reproduces high-fidelity FE temperature fields with less than 1% relative error while achieving 227-fold faster GPU runtimes. Applied to a part-scale
laser scanning study [Ramani et al., Additive Manufacturing 52 (2022) 102643], the method shows that accounting for evaporation and latent heat more than halves their proposed processing metric. The source code of the SG heat solver and some worked examples are available at https://github.com/manasvupadhyay/spectral_galerkin_heat under the Apache 2.0 license.
Read the full abstract ▾
High Energy Physics (Theory)
Dirac oscillator in a self-gravitating cosmic string: confinement spectra beyond the conical approximation
Edilberto O. Silva
The gravitational field of a physical
cosmic string is regular on the axis, curved across a finite
vortex core, and only asymptotically conical. We test whether the bound-state spectrum of a transverse Dirac oscillator resolves this structure beyond the ideal-cone approximation. The
fermion is treated as a test field on self-consistent Einstein–Abelian-
Higgs vortex backgrounds, and the radial problem is cast as a generalized Hermitian
eigenvalue problem. The numerical formulation is checked against the exact Minkowski and ideal-cone spectra and by independent shooting calculations. For a reference
vortex family, the finite-core correction grows from the weak-confinement regime toward the percent level. When the normalized asymptotic cone is held fixed, the spectrum still varies with the measured
Higgs-core radius, and the sampled backgrounds bracket a change of sign of the ground-state correction. The bound-state spectrum therefore contains information about the resolved core profiles that is not fixed by the asymptotic cone alone.
Read the full abstract ▾
General Physics
Constraining a model supported in Moiré gravity with a recent data release
J. A. Astorga-Moreno, Miguel A. García-Aspeitia, A. Hernández-Almada et al. (+1 more)
Moiré theory is a revolutionary alternative arising from solid-state physics that can be extended to
gravity, forming a framework called Moiré
gravity. The idea behind it is that Einsteinian
gravity has a validity limit and must be extended to Moiré
gravity, in which the Friedmann equation changes and a new scalar field emerges. In this vein, in this paper, we propose an analytic solution for the Moiré scalar field coupled with the modified Friedmann equation, studying the viability and constraining the value for the main parameter of the scalar field and cosmology in general, through the use of
datasets that contain
cosmic chronometers, type Ia
supernovae, intermediate-luminosity
quasars, and hydrogen II
galaxies. Our results allow for an accelerated phase with two peaks, but also predict an extremely decelerated stage, with $q(z=0)=15.376^{+6.403}_{-4.692}$ when the characteristic parameter of the theory is $\jmath=0.677^{+0.001}_{-0.002}$, in contrast to other models that decelerate at $z=0$.
Read the full abstract ▾
All authors J. A. Astorga-Moreno, Miguel A. García-Aspeitia, A. Hernández-Almada, E. A. Mena-Barboza
Atmospheric and Oceanic Physics
Aries: A Proprietary Medium-Range Weather Prediction Model for the Energy Industry
Lukas Hedegaard Morsing, Arian Bakhtiarnia, Jonas Lynge Olesen et al. (+2 more)
Medium-range weather
forecasting underpins operational and planning decisions across the energy industry. Developing competitive weather models was once the domain of national meteorological centers, but recent advances in machine-learned weather prediction (MLWP) have opened the field to industry. We present Aries, a SwinTransformer-based MLWP model developed at InCommodities. Aries is trained on ERA5 reanalysis data at 0.25\textdegree{} resolution, predicting 74 prognostic and 11 diagnostic atmospheric variables. We evaluate the model on 2025 ECMWF Analysis initializations, ensuring a recent and strictly out-of-sample test period for all models compared. On 10-metre wind speed, Aries outperforms both ECMWF HRES and AIFS in terms of RMSE for lead times up to four days, while on 2-metre temperature it achieves RMSE on par with AIFS operational. These results demonstrate that proprietary development of competitive weather models is technically viable, supporting a broader set of forecasts available for operational and planning applications in the energy industry.
Read the full abstract ▾
All authors Lukas Hedegaard Morsing, Arian Bakhtiarnia, Jonas Lynge Olesen, Tómas Bragi Björnsson Leth, Christian Gøbel Bach
Medical Physics · Cross-listed from q-bio.QM
PyFLI: A Python Library for Simulation, Parameter Estimation, and Benchmarking in Fluorescence Lifetime Imaging
Vikas Pandey, Ismail Erbas, Margarida Barroso et al. (+2 more)
Fluorescence lifetime imaging (FLI) measures the temporal decay of fluorescence after excitation and provides quantitative information about a fluorophore's local environment and molecular interactions. Depending on the fluorophore and experimental design, lifetime can report changes associated with pH, oxygenation, cellular metabolism, and Forster resonance energy transfer. These properties make FLI useful across microscopy, biophysics, biomedical optics, and preclinical imaging, where the same type of molecular contrast can be studied across different biological scales. FLI measurements, however, are acquired with instruments that record fluorescence in different ways. Intensified charge-coupled device (ICCD) cameras, single-
photon avalanche diode (SPAD) arrays, and time-correlated single-
photon counting (TCSPC) systems differ in temporal sampling, data organization, detector noise, instrument response, and file format. Lifetime-estimation methods also make different assumptions about the recorded decay, while learning-based approaches require realistic training and validation data for which the underlying parameters are known. PyFLI is an open-source framework for FLI processing and standardized data simulation. It imports measurements from acquisition systems, simulates labeled data under configurable acquisition and noise conditions, and provides complementary approaches for parameter estimation. These include nonlinear least-squares fitting (NLSF), maximum-likelihood estimation (MLE), phasor analysis, rapid lifetime determination (RLD), Laguerre-based estimation, and optional
Bayesian and deep-learning inference. CPU and GPU processing support image-scale analysis, while reconstruction, visualization, statistical analysis, and cross-software comparison provide tools for evaluating results. PyFLI includes compressed-sensing reconstruction for single-pixel hyperspectral FLI.
Read the full abstract ▾
All authors Vikas Pandey, Ismail Erbas, Margarida Barroso, Stefan Radev, Xavier Intes
Materials Science
Crystallographic and Electronic Phase Changes in TiTe2 via Atmospheric and Electron Beam Exposure
Bishal Pokhrel, Joel Quarnstrom, Saraswati Shrestha et al. (+4 more)
In this study, we examine the surface sensitivity of a transition metal dichalcogenide (TiTe2) grown using the Chemical Vapor Transport (CVT) technique at high pressure and study the surface changes in the sample upon exposure to air as well as its crystallographic properties upon e-beam exposure. We examine the local density of States (LDOS) of the mechanically exfoliated sample surface before and after exposure using Scanning Tunneling Microscopy/Spectroscopy (STM/STS) and find a metal-to-
semiconductor transition at the surface. The STM analysis shows a clear change in surface roughness which indicates the formation of an adlayer on the surface of the sample. The
crystal structure was examined using X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM), indicating a phase transition from a single-crystalline hexagonal phase to a polycrystalline state via a distorted monoclinic phase. Furthermore, the presence of a possible superlattice suggests non-stoichiometric TixTey at the surface of the exposed layer.
Read the full abstract ▾
All authors Bishal Pokhrel, Joel Quarnstrom, Saraswati Shrestha, Halle Helfrich, Elena Echeverria, David N. McIlroy, Andrew J. Yost
Biological Physics
Double-well potentials and crucial estimations in nonlinear dynamics of microtubules
Rama Gupta, Nicolina Pop, Dragana Ranković et al. (+1 more)
In the present work, we study the two-component model of microtubules, the basic components of the eukaryotic cytoskeleton. We introduce a couple of estimations, which tremendously simplified the model. The paper is devoted to tangential oscillations of dimers, but we explain that the model can explain the radial oscillations as well. Finally, we study the stability of all solutions of differential equations, describing the dynamics of the microtubules.
Read the full abstract ▾
All authors Rama Gupta, Nicolina Pop, Dragana Ranković, Slobodan Zdravković
Optics
Quantum eraser enables single-shot quantum holography with undetected photons
Naru Yoneda, Nao Sakiyama, Luis Ordonez et al. (+3 more)
Quantum holography with undetected
photons (QHUP) enables the complex amplitude of infrared to be acquired beyond the sensitivity range of silicon based sensors, through induced coherence withoud induced emission. QHUP generally requires multiple phase-shifted holograms to retrieve the complex-amplitude distribution of an object, which limits measurement stability and temporal resolution. Although classical parallel phase-shifting holography provides a favorable balance between temporal and spatial resolution, it has not previously been implemented in QHUP because of the constraints imposed by
photon distinguishability. In this study, we propose a
quantum eraser-based
geometric phase-shifting QHUP. By accurately erasing not only polarization distinguishability but also temporal distinguishability arising from differences in the optical paths, the complex-amplitude distribution of an object can be retrieved in a single shot using a silicon-based image sensor equipped with a polarization-filter array. This single-shot acquisition, combined with real-time processing, enables the observation of dynamic objects in the near-infrared spectral region. To the best of our knowledge, these experimental results constitute the first real-time acquisition of the complex-amplitude distribution of a near-infrared object using QHUP with a silicon-based image sensor equipped with a polarization-filter array. Furthermore, to enhance the reproducibility and applicability of this study, the experimental optical setup, bill of materials, and source code for real-time imaging have been made openly available. The ability to retrieve the complex-amplitude information carried by undetected
photons in real time is expected to extend the applicability of QHUP to a wide range of fields, including spectroscopic imaging and
semiconductor inspection.
Read the full abstract ▾
All authors Naru Yoneda, Nao Sakiyama, Luis Ordonez, Vishal Prajapati, Kanako Yoshimura, Osamu Matoba
High Energy Physics (Phenomenology)
Unitarity dressing of the dynamical gluon mass scale
T. V. Iser, V. Li and E. G. S. Luna
We examine how $s$-channel unitarization changes the dynamical
gluon mass scale $m_g$ inferred from high-energy elastic $pp$ scattering. The Born input is the Reggeized Landshoff–Nachtmann exchange of two nonperturbative
gluons in a color-singlet state. We fit the ATLAS and TOTEM forward data separately, using eikonal and $U$-
matrix unitarizations with logarithmic and power-law running masses derived from Schwinger–Dyson analyses. At the common reference cut $|t|_{\rm max}=0.12~\GeV^2$, the Born fits give $m_g=297$–$427~\MeV$; the eikonal and $U$-
matrix fits give $265$–$360~\MeV$ and $243$–$328~\MeV$, respectively. Unitarization changes the fitted values of the intercept parameter $\epsilon$, $m_g$, and the exponential slope $a_1$ of the
proton form factor together. Over $0.10\leq |t|_{\rm max}\leq0.14~\GeV^2$, the $U$-
matrix parameters vary less with the cut, while the eikonal fits to TOTEM show a pronounced drift. Replacing the infrared continuation of the logarithmic effective charge by a Curci–Ferrari prescription changes $m_g$ by a mean absolute relative shift of $1.77\%$ over twenty comparisons, with a maximum of $2.17\%$. The inferred scale remains in the few-hundred-MeV region, but its fitted value depends on the nonperturbative input and on the unitarization prescription.
Read the full abstract ▾
Instrumentation and Methods for Astrophysics
Towards High-Throughput Visible Photonic Lanterns for the EMARCOT Project
Abani Shankar Nayak, Julius Goehring, Marina Centenera-Merino et al. (+14 more)
Photonic EMARCOT is an innovative project involving Spanish, German and Australian research institutes that aims to integrate multiple Optical Tube Assemblies (OTAs) using photonic lanterns. The "Pathfinder" prototype, featuring seven OTAs with a 1.1-meter effective aperture, will feed a spectrograph at the Calar Alto Observatory, with first light expected in 2026. We report the fabrication and experimental evaluation of a custom 7x1 multi-mode photonic lantern (MMPL) developed for this framework, featuring seven 25 um core multi-mode inputs merging into a single 50 um core multi-mode output optimized for the visible wavelength range (400-700 nm). Optical characterization centered at 600 nm reveals exceptional channel-to-channel uniformity, with statistical variations close to zero across both bare-fiber and connectorized MMPL configurations. However, the total baseline throughput of this initial device was limited to below 4%. From the refractive index studies, this low throughput is attributed to severe refractive index mismatch between the internal fiber cladding geometry and the structural capillary, which suppresses total internal reflection during the tapering transition. This work establishes an important diagnostic baseline that highlights the necessary fabrication tolerances needed to improve future high-throughput manufacturing processes for precision radial-velocity astronomy.
Read the full abstract ▾
All authors Abani Shankar Nayak, Julius Goehring, Marina Centenera-Merino, Pedro José Amado-González, David Pérez-Medialdea, Mabel Ruiz-Lopez, Francisco J. Pozuelos, Miguel Andrés Sánchez Carrasco, José Luis Ortiz Moreno, Jesús Aceituno-Castro, Stefan Cikota, Javier Flores, Christopher Betters, Andrew Ross-Adams, Sergio Leon-Saval, Martin M. Roth, Kalaga Madhav
Materials Science · Cross-listed from cs.CV
Symmetry-aware super-resolution of crystal orientation maps via invariant latent-space learning
Umang Garg, Warren Zamudio, McLean P. Echlin et al. (+3 more)
Crystal-orientation maps are physical fields defined only up to
crystal symmetry; electron backscatter diffraction (EBSD) resolves them experimentally, but acquisition-time constraints limit spatial resolution. Unlike conventional images, EBSD data lie on the quotient space $\mathrm{SO}(3)/G$, where $G$ is the
crystal-
symmetry group. Standard Euclidean interpolation can therefore mix
symmetry-equivalent representations and blur grain boundaries. We introduce the
Symmetry-Group-Aware Super-Resolution
Attention Network (SG-SRAN), which incorporates
crystal symmetry and boundary preservation by design. A frozen, locally isometric encoder maps equivalent orientations to a common latent representation in which Euclidean distance approximates misorientation. Super-resolution is performed in this space, with each high-resolution
token restricted to a feature-consistent local support to prevent cross-boundary mixing. A dictionary-based decoder then recovers valid orientations. Across FCC and HCP
benchmarks, SG-SRAN matches 15-16 million parameter backbones using only 27-49k trainable parameters, while achieving the lowest p68 errors, highest inverse-pole-figure fidelity, and zero-shot transfer to unseen
alloys.
Read the full abstract ▾
All authors Umang Garg, Warren Zamudio, McLean P. Echlin, Samantha H. Daly, Tresa M. Pollock, B.S. Manjunath
Astrophysics of Galaxies
Impact of LSST systematics on stellar-stream density fluctuations for dark matter
Matthieu Pélissier, Peter S. Ferguson, Alex Drlica-Wagner et al. (+6 more)
The Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) is expected to significantly advance the study of Milky Way
stellar streams. In particular, the deep, precise photometry from LSST should greatly increase the statistical sensitivity to density fluctuations in
stellar streams, which can be used to probe the small-scale distribution of dark matter. However, current forecasts generally neglect the impact of observational systematics that will be imprinted on stream density measurements. In this study, we develop a realistic forward-modeling framework to inject
stellar streams into LSST-like observations including photometric uncertainties, survey depth variations, background contamination, and imperfect
star-
galaxy classification. We develop a likelihood-ratio analysis to assess the detectability of gaps in
stellar streams in the presence of these observational systematics. In the presence of realistic survey systematics, we find that after four years of operations, LSST will be sensitive to density reductions of $\sim50\%$ for gaps with widths of $5$ deg in streams with surface brightness of $\sim33$ mag arcsec$^{-2}$. Relative to the ideal case, this corresponds to a degradation in gap depth sensitivity by a factor of $\sim5$ due to the combined impact of background contamination and observational systematics. Assuming a simplified analytical mapping between gap depth and dark matter subhalo properties, these estimates correspond to a minimum detectable subhalo mass of $\sim1\times10^7$ M$_\odot$. Observational effects shift this accessible mass scale upward by a factor of $\sim16$, with background contamination contributing a factor of $\sim5$ and survey systematics a further factor of $\sim3$, dominated by
star-
galaxy classification.
Read the full abstract ▾
All authors Matthieu Pélissier, Peter S. Ferguson, Alex Drlica-Wagner, Marine Kuna, David Maurin, Christian Aganze, Johann Cohen-Tanugi, Yao-Yuan Mao, The LSST Dark Energy Science Collaboration
Instrumentation and Detectors
Mitigating Sensor Cracking using the Interposer Strategy in the ATLAS ITk Strip Detector
ATLAS ITk Strips Collaboration
This paper introduces the strategy of using an interposing layer to mitigate thermal-stress-induced fracturing of silicon sensors in ATLAS ITk Strip modules. This strategy involves a change in the module design in which layers of soft adhesive and a kapton separator, known as an interposer, are added to the module stack-up to decouple thermal stresses. This paper discusses the interposer design and its implementation in the ATLAS ITk Strip barrel, including material tests to validate the additional components, the development of new processes to integrate the new layers into the module assembly workflow, results from design validation and quality control testing of prototype interposed modules, and studies indicating that the new design significantly reduces the thermal stress experienced by the sensor. Tests of prototype support structures loaded with interposed modules have shown no sensor fractures in the relevant temperature range for operation in ATLAS, resulting in the adoption of the interposer strategy as the primary sensor cracking mitigation in the ATLAS ITk Strip barrel.
Read the full abstract ▾
General Relativity and Quantum Cosmology
WKB approximation for quasi-bound states and trapped modes
R. A. Konoplya, Z. Stuchlík and A. Zhidenko
We develop a largely automatic semi-analytic method for calculating weakly damped quasi-bound states and trapped modes supported by a local minimum of an effective potential. The real part of the frequency is obtained from an arbitrarily high-order local WKB expansion and Padé resummation, while the exponentially small imaginary part is estimated using the Gamow approximation for tunnelling through one or two potential barriers. Because the local quantization requires only derivatives of the potential at its minimum, the method applies readily to non-rational effective potentials and to different compact-object geometries. We provide a Mathematica notebook implementing the procedure. Comparisons with continued-fraction and direct numerical results for massive scalar fields around Schwarzschild and Kerr black holes and for axial trapped modes of a uniform-density
star show that the method yields accurate real frequencies and useful estimates of decay rates outside the superradiant regime.
Read the full abstract ▾
Quantum Physics
Threshold Behavior of ZX and ZY Surface Codes Under Circuit-Level Biased and Crosstalk Noise
Pritesh Thakur and Jean-François Van Huele
Studying the threshold behavior of surface codes under biased noise models is an active area of research. Previous work Tuckett et al. (2018), using an optimal tensor-network decoder, demonstrated that replacing $Z$-type stabilizers with $Y$-type stabilizers significantly improves the surface code threshold under code-capacity level dephasing noise. In this work, we construct and study a $ZY$ surface code by replacing the $X$-type stabilizers with $Y$-type stabilizers. We compare it with the standard $ZX$ surface code under
circuit-level Pauli-$X$ biased noise, with and without an additional gate-based $XX$ crosstalk noise. We find that for the $ZX$ surface code, the $X$-
memory threshold increases monotonically with bias while the $Z$-
memory threshold decreases and saturates. For the $ZY$ surface code, the $Y$-
memory threshold is nearly constant across all bias values. The $Z$-
memory thresholds of the $ZX$ and $ZY$ codes are consistent within the uncertainty. Adding $XX$ crosstalk reduces the $Z$-
memory threshold beyond the fitting uncertainty while leaving the $X$
memory threshold largely unaffected. The choice of CNOT ordering redistributes threshold performance between the two logical
memories. Our work extends prior observations from code-capacity level noise to
circuit-level noise. It also indicates the need for decoders capable of jointly
reasoning over correlated syndrome information so that tailored stabilizer structures could be fully utilized for
quantum error correction.
Read the full abstract ▾
Adaptation and Self-Organizing Systems · Cross-listed from q-bio.NC
Cortical information transfer reveals conserved hemispherical network dynamics across human handedness
Yago Emanoel Ramos and José Garcia Vivas Miranda
Whether human motor and
brain lateralization arises from fundamentally distinct neural architectures or emerges from conserved network dynamics remains a central question at the intersection of network science and neurobiology. Conventional measures of cortical activation often fail to resolve how directed information exchange adapts to manual preference during complex motor tasks. This ambiguity leaves it unclear whether left-handed individuals possess atypical neural organization or follow shared dynamical principles. Here, we combine Permutation Transfer
Entropy (PTE) with network-based indices to map directed cortical signal flow using electroencephalography (
EEG) during high-precision motor execution (handwriting) in both right- and left-handed individuals. We demonstrate that cortical communication is strictly scale-dependent regardless of handedness: ipsilateral dominance occurs primarily in general, network-wide interactions, whereas inter-hemispheric interactions maintain a contralateral profile. Crucially, left-handed individuals exhibit inter-hemispheric information dynamics that are functionally equivalent to right-handers when executing tasks with the same anatomical hand, refuting assumptions of mirrored or atypical lateralization. By demonstrating that human cortical lateralization relies on dynamical principles conserved across manual preferences, these findings suggest that functional asymmetries reflect adaptive optimizations governed by epigenetic or social flexibility, rather than fixed structural divergences.
Read the full abstract ▾
Astrophysics of Galaxies
Studying Outflows with Synthetic Absorption Line Spectra from High Resolution Simulations
Jake Magee, Evan Schneider, Kate H. R. Rubin et al. (+2 more)
Down-the-barrel absorption line spectra are a powerful probe of the properties of multiphase
galactic outflows. In this work, we demonstrate a method to generate realistic synthetic spectra using high resolution ($\Delta x=5-20 \ \mathrm{pc}$), 20-kiloparsec-scale
outflow simulations from the next generation of the CGOLS project. Aiming to mimic modern observational surveys of nearby
star-forming
galaxies, we generate a suite of UV absorption lines, from which we measure common observables such as equivalent widths and velocity statistics, and compare them to observed values. The velocity statistics from the simulated data agree well with high-resolution, far-UV HST treasury data, but the equivalent widths (EWs) display more variability. Our fiducial EWs are systematically lower than the empirical predictions by $\sim50-97\%$, particularly in the lines with higher ionization potentials, though these values increase with inclination angle,
star formation rate, and time. We find a strong correlation between the measured
outflow velocity and ionization potential, reminiscent of the known correlation between velocity and temperature from the simulations. We also study the effect of simulation resolution on our statistics, finding the EWs to be much more sensitive to the simulation resolution than the velocities. Overall, we find that we can generate realistic synthetic spectra from high-resolution hydrodynamic simulations that are qualitatively similar to observations. In future work, we will further improve the physical realism of our synthetic spectra by implementing a more accurate ionizing background spectrum, with the ultimate goal of improving constraints on derived
outflow properties from observations.
Read the full abstract ▾
All authors Jake Magee, Evan Schneider, Kate H. R. Rubin, S. Alwin Mao, Cameron Hummels
High Energy Physics (Theory)
Presymplectic BV-AKSZ and constrained DGCAs
Maxim Grigoriev, Alexander Mamekin and Dmitry Rudinsky
The AKSZ construction encodes the Batalin-Vilkovisky formulation of a topological field theory in terms of finite-dimensional
geometric data. There are at least two ways to extend this approach to nontopological gauge theories. The first, due to Costello, replaces the spacetime exterior
algebra with a more general DGCA that is not freely generated. The second replaces the
symplectic structure with a degenerate presymplectic structure, which may also be non-regular. In this work, we show that both approaches are special cases of a more general algebraic AKSZ construction, in which the underlying
algebras are allowed to be constrained and the presymplectic structure may be degenerate and non-regular. Within this framework, we explicitly relate Costello's formulation of the Chalmers-Siegel model to the presymplectic formulation, the latter admitting a first-principles derivation. We also construct Costello-like formulations of higher-form analogues of the Chalmers-Siegel model and of self-dual higher-
spin gauge theories of Yang-Mills type, obtaining in the latter case a remarkably concise description. In so doing we propose a simple algebraic construction for the corresponding source space DGCAs underlying these examples.
Read the full abstract ▾
Computational Physics
A new generation of effective core potentials: Selected heavy 5d and 6p elements
Omar Madany and Lubos Mitas
We expand the correlation-consistent effective core potentials (ccECPs) library by developing semi-local pseudopotentials and matching basis sets by heavy-elements from $5d$ (Hf, Os, Hg) and $6p$ (Tl, Po, At, Rn) blocks. In order to accurately capture scalar relativistic effects,
spin-orbit coupling, and electron-electron correlation, we implement a tiered core-valence partitioning strategy across three distinct resolutions. This includes a small 60-core (Hf, Os, Hg) that explicitly correlates subvalence shells, a large 78-core definition for the main-group elements that rigorously accounts for core polarization and relaxation effects in sparse valence environments, and an intermediate 68-core partition for Hg and Tl. This 68-core architecture represents a unique development in the ccECP library, optimizing the balance between accuracy and computational efficiency in a manner unexplored for ligther elements. Optimized against relativistic all-electron CCSD(T) references, the ccECPs deliver outstanding atomic precision, achieving a global average atomic low-lying states deviation of just 0.045 eV. This accuracy translates directly to robust molecular transferability, systematically restricting dissociation energy discrepancies to under 0.03 eV,
equilibrium bond lengths to within 0.005 Å. By enforcing a regularized, finite potential at the origin for enhanced numerical stability in
stochastic quantum Monte Carlo methods, this library removes a critical methodological bottleneck for predictive many-body simulations of heavy-element systems and materials.
Read the full abstract ▾
Earth and Planetary Astrophysics
Constraining Tidal Migration with the Hot Jupiter Population
Linhao Ma, Yubo Su, Samuel W. Yee et al. (+3 more)
Hot Jupiters with orbital periods shorter than a few days have probably been affected by
tidal orbital migration. We develop an analytical framework for constraining
tidal migration from the present-day hot Jupiter period distribution, taking into account the uncertain rate and period distribution of hot Jupiters produced by mechanisms such as high-eccentricity migration or disk-driven migration. Assuming the
tidal migration timescale is proportional to $P^{\chi_\tau}$, solutions with $\chi_\tau \simeq 3, 1.7,$ and 5.6 are all compatible with the present-day period distribution. The $\chi_\tau \simeq 3$ solution is consistent with
equilibrium tides with suppression of dissipation at short periods, and implies that newly circularized hot Jupiters have periods concentrated near $3-4$ days, as predicted in some high-eccentricity migration models. The $\chi_\tau \simeq 1.7$ solution is also compatible with the $3-4$ day peak but has no clear counterpart in existing
tidal theories and is more finely tuned. The $\chi_\tau \simeq 5.6$ solution is compatible with enhanced short-period
equilibrium tidal dissipation or weakly nonlinear
gravity-wave dissipation, but requires circularization at unexpectedly short periods. Thus, we find the model with $\chi_\tau \simeq 3$ most appealing. Transit timing of individual systems and observational constraints on the rate of hot Jupiter engulfment provide additional constraints, which are presently inconclusive but should improve with future data. Improved measurements of the occurrence of short-period
planets as a function of
planet mass and system age could also help to sharpen the constraints on
tidal migration.
Read the full abstract ▾
All authors Linhao Ma, Yubo Su, Samuel W. Yee, Caleb Lammers, Eliot Quataert, Joshua N. Winn
Accelerator Physics
Turn-by-turn Tune Analysis Using Adaptive BPM Ensembles in the Fermilab Mu2e Delivery Ring*
D. Steinkamp
The Mu2e experiment at Fermilab requires stable resonant slow extraction from the Delivery Ring, making reliable tune monitoring an important operational diagnostic. This work investigates BPM-based tune-candidate extraction using synchronized turn-by-turn position data distributed across multiple digitizers. Each spill contains approximately 50,000 turns from many BPMs in both transverse planes, enabling spectral analysis of tune-like structure. The analysis captures coherent spill snapshots, verifies synchronization using stream timestamps, and computes tune candidates in configurable horizontal and vertical tune bands. Rather than relying on a single BPM or fixed BPM list, it evaluates BPM quality on a spill-by-spill basis and selects small adaptive BPM ensembles. A multi- spill study shows that tune observability is distributed and dynamic rather than concentrated in one globally optimal BPM. Adaptive ensembles improve tune-candidate quality compared with single-BPM selections, with the clearest results in the vertical plane. The horizontal plane shows useful ranking structure but weaker visibility under present thresholds. Direct evaluation of fixed global BPM sets shows that static selections do not reproduce dynamic per-spill performance. These results motivate an adaptive BPM-ensemble approach for Delivery Ring tune analysis using selected BPM subsets, confidence metrics, and quality flags rather than a single preferred BPM or fixed BPM list.
Read the full abstract ▾
Fluid Dynamics · Cross-listed from math.DS
The three-vortex system: Hopf fibration, symplectic reduction, and near-collisions
Thierry Gallay and Vladimir Sverak
We study the dynamics of collisions and near-collisions in the system of three point
vortices in the plane. The dynamics is known to be completely integrable and can be reduced to the study of
Hamiltonian systems on two-dimensional
symplectic leaves. This still allows for interesting behavior of the solutions, various aspects of which have been investigated in a large body of work by many authors. Our focus will be on collisions and the possibility of their regularization through perturbations of suitable parameters of the system. We will use the reduced coordinate given by $\zeta=(z_2-z_1)/(z_3-z_1)$, where $z_1,z_2,z_3$ are the complex numbers representing the positions of the
vortices. This choice seems very natural, although we have not come across it in the existing literature on the topic. Some of our results concerning the near-collision behavior appear to be new, and we also prove inequalities between critical energy values that we have not found in the literature. The calculations we do to analyze the collisions and near-collisions also reproduce various classical results that were previously obtained by other authors using different coordinates, and parts of the paper therefore have an expository character.
Read the full abstract ▾
High Energy Astrophysical Phenomena
XRISM observations of the Perseus cluster along two arms: Chaotic ICM motions probed by resonant scattering
Annie Heinrich, Irina Zhuravleva, Congyao Zhang et al. (+13 more)
XRISM has mapped gas velocities across the core of the Perseus cluster, separating the kinematic effects of mergers and AGN feedback. The physical properties of these motions remain unclear: are they a superposition of bulk flows, predominantly random/turbulent motions, or a mixture of both? Without resolving this question, constraints on the nonthermal pressure fraction and heating rate remain uncertain, as both assume predominantly random motions. Unlike emission line broadening, resonant scattering is most sensitive to small-scale, random motions rather than coherent bulk flows. Taking advantage of the extensive XRISM coverage of the Perseus cluster, we detect the full effects of resonant scattering on the He{\alpha} w line for the first time. This includes flux suppression in the cluster center, enhancement in the outer regions, and non-Gaussianity in the emission line. We employ radiative transfer simulations to constrain the amplitude of small-scale ICM velocities in the inner 60 kpc of Perseus, finding them to be consistent with the line broadening measurements within the uncertainties. This indicates the observed velocity dispersion is primarily due to small-scale random motions in the central Perseus regions rather than coherent bulk flows. We further explore potential anisotropy of these motions, showing that they are consistent with isotropic or radial motions rather than tangential ones. Longer XRISM observations are required to improve these anisotropy constraints. Finally, we explore azimuthal variations between the two complete radial arms observed by XRISM.
Read the full abstract ▾
All authors Annie Heinrich, Irina Zhuravleva, Congyao Zhang, Anna Ogorzalek, Ayşegül Tümer, François Mernier, Phillip C. Stancil, Elena Bellomi, Lior Shefler, John ZuHone, Yutaka Fujita, Julie Hlavacek-Larrondo, Yuto Ichinohe, Kyoko Matsushita, Nhut Truong, Shutaro Ueda
Nuclear Experiment
A detailed view at magnetic dipole strengths: The case of semi-magic $^{50}$Ti
B. Kelly, M. Spieker, U. Friman-Gayer et al. (+14 more)
Magnetic dipole, $M1$, strengths were studied in semi-magic $^{50}$Ti up to the
neutron-separation threshold by combining data from $(d,p)$ one-
neutron transfer, $(\gamma,\gamma')$ real-
photon scattering, $(e,e')$ inelastic scattering at extreme backward angles, and $(p,p')$ at $E_p = 210$ MeV and extreme forward angles. The combination of all probes provided unique access to the
neutron spin-flip contribution and the possibility to evaluate its role in generating the
spin-flip $M1$ strengths. The small contribution of the
neutron $(1f_{7/2})^{-1}(1f_{5/2})^{+1}$
spin-flip transitions, which were probed with the $(d,p)$ reaction, to the overall strength in $^{50}$Ti questions the standard picture for the microscopic origin of
spin-flip strength in the $fp$ shell. For $^{50}$Ti, this letter shows that $J^{\pi} = 1^+$ states with larger
neutron $(1f_{7/2})^{-1}(1f_{5/2})^{+1}$ spectroscopic factors do not correspond to the ones with the largest $B(M1;0^+_1 \rightarrow 1^+_i)$ strengths.
Read the full abstract ▾
All authors B. Kelly, M. Spieker, U. Friman-Gayer, L. T. Baby, T. Beck, A. L. Conley, S. W. Finch, J. Isaak, Krishichayan, E. Litvinova, H. Pai, N. Pietralla, D. Savran, W. Tornow, N. Tsoneva, A. Volya, V. Werner