Strongly Correlated Electrons
Orbital-selective oxygen holes in cuprate ladders beyond the Zhang-Rice paradigm
Chengyun Hua, Tianran Chen, Isaac C. Ownby et al. (+13 more)
The electronic structure of the
spin-ladder cuprate Sr14Cu24O41 challenges the presumed universality of the Zhang-Rice singlet (ZRS) framework and models based exclusively on Cu-O hybridized orbitals. Combining polarization-dependent resonant soft X-ray scattering at the O K-edge with inelastic
neutron scattering, we show that doped holes in the Cu2O3 ladders localize predominantly in planar non-bonding O 2pz (p{\pi}) orbitals of rung oxygen sites rather than forming conventional ZRS states. Polarization-resolved RSXS uniquely identifies this orbital assignment, while
lattice and
magnetic excitations reveal its coupled consequences, establishing a unified microscopic picture that excludes the conventional {\sigma}-bonded singlet. This oxygen-sublattice charge order produces an anomalous diagonal stretching
phonon and explains the absence of incommensurate
magnetic fluctuations and anomalous
magnon splitting. These findings motivate a reassessment of hole pairing in ladder cuprates and the sufficiency of copper-centric models for cuprate
superconductors.
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All authors Chengyun Hua, Tianran Chen, Isaac C. Ownby, Colin L. Sarkis, Garrett Granoth, Masaaki Matsuda, Jiaqiang Yan, Ho Nyung Lee, Jeongkeun Song, Yuya Shinohara, Masatomo Uehara, Jun Akimitsu, Oleksandr Prokhnenko, Eugen Weschke, Takeshi Egami, D. Alan Tennant
Astrophysics of Galaxies
Electron temperature and emission measure of HII regions in the central molecular zone (CMZ) from H40 \alpha recombination line and continuum emissions by ALMA CMZ Exploration Survey - ACES -
Yoshiaki Sofue, Steven N. Longmore, Daniel Walker et al. (+40 more)
Star formation activity in the Central Molecular Zone (CMZ) directly manifests itself as
radio continuum free-free emission (Bremsstrahlung) and
radio recombination line emission from HII regions surrounding newly formed massive
stars. We derive the overall distribution of the HII regions and their fundamental properties: electron temperature ($\Te$) and emission measure ($EM$), and hence electron density in the form of two dimensional distribution maps over the CMZ by analyzing the ACES (ALMA CMZ Exploration Survey) \h40 (99.02 GHz) recombination line and 99.6 GHz continuum emission data with synthesized beam widths of $2''.45$ (0.097 pc at 8.2 kpc) and $2''.14$, respectively. We apply the 'TeEM' method ($\Te$–$EM$ mapping), which creates $\Te$ and $EM$ maps from input 2D maps of the continuum and integrated line intensity. The analysis covers the entire ACES field from $l\sim -0^\circ.6$ to $+0^\circ.8$ and from $b\sim -0^\circ.2$ to $+0^\circ.1$. The area analyzed is complete and includes previously known HII regions such as Sgr B2, Sgr B1, the Sickle, the Pistol, thermal filaments (Bridges), Sgr A HII regions, the Minispiral, and many other known HII regions. Sgr C is not included in the analysis due to the insufficient signal-to-noise ratio in the recombination line map. The mean electron temperature over the CMZ is determined to be $\Tcmz= 5872 \pm 78 ~{\rm (SE)} ~\pm 3682~{\rm (SD)}$ K (SE:standard error of the mean, SD: pixel-to-pixel standard deviation). Some HII regions, such as Sgr B2 Main and the Minispiral, exhibit large scatter and an internal $\Te$ gradient of several thousand K per parsec. The $EM$ distribution is more diverse, varying by orders of magnitude from $\sim 10^5$ to $\sim 3\times 10^8$ \emunit within the CMZ, as well as within individual HII regions.
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All authors Yoshiaki Sofue, Steven N. Longmore, Daniel Walker, Adam Ginsburg, Jonathan D. Henshaw, John Bally, Ashley T. Barnes, Cara Battersby, Laura Colzi, Paul Ho, Izaskun Jimenez-serra, Elizabeth Mills, Maya A. Petkova, Mattia C. Sormani, Jennifer Wallace, Robin G. Tress, Nazar Budaiev, Rojita Buddhacharya, Christoph Federrath, Zi-xuan Feng, Pablo García, Savannah Gramze, Christian Henkel, Pei-ying Hsieh, Fengwei Xu, Katharina Immer, Dani Lipman, Dariusz C. Lis, Álvaro Sánchez-Monge, Xing Lu, Mark R. Morris, Francisco Nogueras-Lara, JÜrgen Ott, Dylan M. Paré, Jaime E. Pineda, Víctor M. Rivilla, Jairo Armijos-Abendaño, Qizhou Zhang, 6Denise Riquelme-vásquez, Howard a. Smith, Marco Donati, Q. Daniel Wang, N. Bijas
Materials Science
Revealing the Atomic Structure of NiO/Ga$_{2}$O$_{3}$ Interfaces
Michelle A. Smeaton, Krishna Acharya, Anna Sacchi et al. (+5 more)
NiO/Ga$_{2}$O$_{3}$ heterojunctions have garnered significant
attention for use in power electronics due to the ultrawide bandgap and wafer-scale availability of Ga$_{2}$O$_{3}$ and the controllable p-type doping of NiO. However, the structure of NiO/Ga$_{2}$O$_{3}$ interfaces remains underexplored, largely due to the complexity of the junction between their dissimilar cubic and monoclinic
crystal structures. Here we investigate the atomistic structure of the NiO/Ga$_{2}$O$_{3}$ interface for (100), (-201), and (001) oriented Ga$_{2}$O$_{3}$ substrates using aberration-corrected scanning transmission electron microscopy (STEM) in combination with interface modeling and image simulations. We evaluate the abruptness and consistency of the interfaces and compare them to calculated interface models, proposing precise atomic structures and assessing potential structural variation arising from complexity of the monoclinic Ga$_{2}$O$_{3}$
crystal structure. Our interface analysis supports increased focus on (100) oriented Ga$_{2}$O$_{3}$ as a candidate for fabricating high quality, low defect density NiO/Ga$_{2}$O$_{3}$ heterojunction devices. Importantly, we consider the effects of specimen thickness and 3D-to-2D projection during the STEM imaging process to differentiate such effects from real
crystal variations. This work provides insight into the effect of substrate orientation on NiO film and interface quality, creating a pathway to improving heterojunction properties. It further highlights important considerations for interpretation of stability and interlayer phase formation in these interfaces, which is crucial for their integration into reliable and robust power electronic devices.
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All authors Michelle A. Smeaton, Krishna Acharya, Anna Sacchi, Renae N. Gannon, M. Brooks Tellekamp, Andriy Zakutayev, Vladan Stevanovic, Steven R. Spurgeon
Applied Physics
A Concept of LNA with Low Input Impedance Using Common Base BJT for Low-Field MRI
Aleksei A. Nasonov, Mikhail V. Murzin, Nikolay V. Anisimov et al. (+4 more)
Purpose: In
magnetic resonance imaging (MRI), preamplifier decoupling is used to improve the signal-to-noise ratio of a multichannel receive coil array. In low-field and ultra-low-field MRI, low-noise amplifier (LNA) solutions with low input impedance (LII) are poorly represented and consist mostly of field-effect transistors. We propose a low-cost LNA based on a common-base
circuit with bipolar transistors to achieve LII (<5 Ohm), a low noise figure (<1.3 dB), and high gain (>30 dB). Methods: The proposed LNA
circuits were simulated, fabricated, and tested at frequencies of 3 MHz and 21.2 MHz. The decoupling capabilities of the proposed LNA were experimentally evaluated, and MR imaging was performed in a 0.5T MRI scanner alongside a comparative study with a commercial LNA. At 3 MHz, the LNA was evaluated by analyzing free induction decay signals. Results: Proposed LNA solutions demonstrate a low noise figure below 1.3 dB with an input impedance of 3 Ohm. It was also shown that the presented LNA
circuit enables high SNR values in MR imaging. The developed amplifiers demonstrate superior performance compared to available commercial options within the selected HF band. Conclusion: Due to the availability and cost-effectiveness of the selected transistors, the proposed LNA
circuit is highly suitable for low-field MRI applications.
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All authors Aleksei A. Nasonov, Mikhail V. Murzin, Nikolay V. Anisimov, Vasily S. Severikov, Anna A. Dyatlovich, Anna A. Hurshkainen, Georgiy A. Solomakha
Computational Physics · Cross-listed from math.NA
A Volumetrically Stabilized Mixed Formulation of the Finite Element Immersed Boundary Method for Fluid Structure Interaction with Fully Incompressible Hyperelastic Solids
Abhishek Mishra and Paul T. Bauman
The finite element immersed boundary method (FE IBM) with a distributed Lagrange multiplier is an attractive framework for fluid structure interaction (FSI) because it couples an Eulerian description of an incompressible fluid to a Lagrangian description of an immersed solid on two independent, nonconforming meshes, avoiding the costly remeshing required by body fitted arbitrary Lagrangian Eulerian methods. When the immersed solid is modelled as a fully incompressible hyperelastic material, however, a direct finite element discretization of the deviatoric solid stress fails to enforce the Lagrangian incompressibility constraint, and the computed structure exhibits spurious volumetric instabilities and locking. In this work we present a mixed formulation of the distributed Lagrange multiplier FEIBM that restores volumetric stability. Following the theory of nearly incompressible hyperelasticity, we augment the solid stress with a volumetric contribution derived from a dilatational strain energy and introduce an additional solid pressure field, enforced weakly, that plays the role of the Lagrange multiplier for the Lagrangian incompressibility constraint J = 1. The resulting formulation is discretized in space by finite elements and in time by an unconditionally stable semi implicit scheme, and is implemented as a reusable Immersed Boundary physics kernel within the GRINS multiphysics framework, built on the libMesh finite element library. The method is verified on three FSI
benchmarks, an elliptically displaced thick ring returning to
equilibrium, a radially stretched incompressible ring, and a disk falling under
gravity in a viscous fluid, for which the mixed formulation removes the volumetric failure observed with the unstabilized formulation and reproduces the analytical terminal velocity of the falling disk to within 1%.
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Instrumentation and Methods for Astrophysics
The final design of GMagAO-X: high-contrast imaging at first-light of the GMT
Jared R. Males, Laird M. Close, Sebastiaan Y. Haffert et al. (+13 more)
GMagAO-X will be the first-light high-contrast imager on the 25 m
Giant Magellan
Telescope. The driving science case for GMagAO-X is characterization of the atmospheres of nearby rocky
exoplanets such as Proxima Centauri b. The revolutionary increase in spatial resolution and sensitivity provided by GMagAO-X will enable detailed study of such
planets for the first time. Additional science cases include: reflected light characterization of mature
giant planets; measurement of young extrasolar
giant planet variability; characterization of circumstellar disks at unprecedented spatial resolution; characterization of
benchmark stellar atmospheres at high spectral resolution; and mapping of resolved objects such as
giant stars and asteroids. These, and many more, science cases will be enabled by a 21,000 actuator extreme adaptive optics (ExAO) system, an integrated coronagraphic wavefront control system with dedicated deformable mirrors, and a suite of imagers and spectrographs. Science-driven performance requirements for GMagAO-X include achieving a Strehl ratio of 70% at 800 nm on 8th mag and brighter
stars, and
exoplanet characterization at
planet:
star flux-ratios of 1e-7 at 4 lambda/D (26 mas at 800 nm) separation. GMagAO-X has been added to the GMT project baseline plan and is in the final design phase, aiming to complete FDR in March, 2027. The instrument is on track to be ready at first-light of the GMT in the mid 2030s. We provide a brief update of the instrument designed to achieve our ambitious performance targets.
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All authors Jared R. Males, Laird M. Close, Sebastiaan Y. Haffert, Victor Gasho, Adam Fletcher, Joseph Boales, Dhruv Lakhani, Maggie Y. Kautz, Doug Kelly, Olivier Durney, Thomas Salanski, Peter Gray, Cody Nelson, Steven Cornelissen, Paul Bierden, Olivier Guyon
Solar and Stellar Astrophysics
Parametric Study of the Torus Instability Threshold
Jun Chen, Bernhard Kliem and Rui Liu
The
torus instability of an arched current channel has been suggested to initiate and drive major
solar and
stellar eruptions. Its threshold, given by the critical decay index of the
equilibrium external poloidal field (the so-called strapping field) at the position of the current channel, is insufficiently known. Here, we carry out a parametric numerical study of the threshold, employing the force-free Titov-Démoulin (TD)
equilibrium of a line-tied partial toroidal current channel and flux rope. This addresses the scatter of the threshold about its canonical value, $n_\mathrm{cr}=3/2$. Values scattering in the range $n_\mathrm{cr}\approx$\,1–2 are typically found in numerical and observational studies of flux rope eruptions on the Sun. For zero external toroidal (guide, or shear) field and approximately semicircular geometry (corresponding to minimal photospheric line-tying), we find the threshold to lie in the theoretically expected range of $\approx$\,1–1.5. An external toroidal field introduces a strong stabilizing effect on the instability, raising the threshold up to $\sim$\,2.5, which can explain observational and numerical results above the canonical value. Line-tying is found to act as a stabilizer as well. We also consider the approximate threshold based on the potential field and find a very good agreement with the exact numerical value, provided the horizontal component perpendicular to the flux rope axis is used to approximate the external poloidal field.
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Instrumentation and Methods for Astrophysics
Sensor fusion on MagAO-X: real time vibration control using accelerometers
Parker T. Johnson, Jared R. Males, Povilas Palunas et al. (+16 more)
Mechanical vibrations are a significant source of residual wavefront error (WFE) in adaptive optics (AO) systems, limiting the performance of high-contrast imaging instruments. We present the design and on-sky deployment of a low-cost, modular accelerometer telemetry system for the MagAO-X extreme AO instrument on the 6.5 m Magellan Clay
Telescope, consisting of piezoelectric accelerometers and a Raspberry Pi-based acquisition system that streams synchronized data to the real-time control computer with microsecond-level timing stability. The system is used to identify dominant
telescope vibration sources and quantify their coupling to AO telemetry, revealing that several narrow-band modes originate from subsystems including the primary mirror glycol pump, secondary mirror actuation system, and
telescope autofocus system. Coherence analysis between the synchronized accelerometer and wavefront sensor telemetry demonstrates that approximately one-third of the residual tip and tilt WFE is correlated with structural vibrations, indicating that accelerometer telemetry provides a promising foundation for future predictive control implementations. These results demonstrate that low-cost accelerometer telemetry provides a practical approach for vibration identification and a foundation for predictive control in current and future AO systems.
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All authors Parker T. Johnson, Jared R. Males, Povilas Palunas, Olivier Guyon, Sebastiaan Haffert, Joseph Long, Vincent Deo, Julien Lozi, Laird M. Close, Maggie Kautz, Jay Kueny, Jialin Li, Joshua Liberman, Miles Lucas, Matthijs Mars, Eden McEwen, Tiffany Nguyen, Elena Tonucci, Katie Twitchell
Quantum Physics
Unextendible stabiliser bases
Markus Frembs
We study incomplete sets of orthogonal stabiliser states that cannot be extended by a further stabiliser state orthogonal to all of its members. Such sets are the stabiliser analogue of unextendible product bases (UPBs), and we thus call them unextendible stabiliser bases (USBs). Leveraging the
symplectic geometry underlying the $n$-qudit Pauli group in
prime local dimension, we explicitly construct USBs for systems of four
qubits and three qudits of odd
prime local dimension. Moreover, we show that these are the respective minimal
qubit, respectively qudit numbers for which such bases exist, and that USBs exist for all $n\geq4$
qubit and for all $n\geq3$ odd-
prime-dimensional qudit systems. Finally, we compare the resource-theoretic aspects of USBs with those of UPBs. We establish that, analogous to the case of UPBs, the orthogonal complement of every unextendible stabiliser set is a stabiliser-free subspace, and its normalised projector is necessarily magic; moreover, it is bound magic in odd
prime dimension, yet need not be for
qubits. We also show that USB unextendibility alone imposes no uniform quantitative obstruction to discrimination by stabiliser operations.
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High Energy Physics (Phenomenology)
QCD-Matched Gluonic Response in Heavy-Quarkonium Born-Oppenheimer EFT: Locality, Channel Factorization, and the Peskin Limit
Arkadiy I. Syamtomov
We formulate a source-dependent QCD-to-BOEFT matching for the gluonic response of a stable compact heavy-quarkonium state. The matched complementary-space resolvent preserves coupled Born-Oppenheimer dynamics, while an exact Feshbach decomposition separates channels retained explicitly from sectors integrated out at the next matching step. Spectral separation, kernel analyticity, and joint propagation-source bounds provide sufficient conditions for a local channel-factorized OPE; otherwise low-energy BO poles and cuts remain dynamical. The weak-coupling pNRQCD response is recovered as a limiting reference problem. With the additional leading-$E1$, large-$N_c$/free-octet assumptions, the source-weighted spectral measure reproduces the established Bhanot-Peskin electric moments and dissociation cut. For a Coulombic
spin-singlet $1S$ state we also obtain the sequential-$M1$ contribution $c_{B,GG}^{(1)ij} =5\pi\alpha_s^2(c_FV_{\rm iso}^{(s)})^2\delta^{ij}/16$ and the covariant-kinetic seagull contribution $c_{B,\mathrm{dia}}^{(1)ij} =-\pi\alpha_s^2\delta^{ij}/4$. These are identifiable components, not the complete
magnetic matching coefficient.
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Optics
Active Electronic Terahertz Imaging for Industrial Applications: From Hardware to the Paradigm Shift by Artificial Intelligence
Aparajita Bandyopadhyay, Hui Yuan, Willie J. Padilla et al. (+2 more)
Imaging with terahertz (THz) radiation (0.3-10 THz) benefits from a unique combination of attributes: penetration through dry, non-polar packaging materials; variations of dielectric functions to provide contrast; the existence of spectral fingerprint resonances for some classes of materials; non-ionizing
photon energies that are safe for use around humans; and - viewed from the low-frequency side - an extension of the capabilities of microwave radar to higher frequencies and thus to substantially better spatial resolution, at wavelengths which still permit direct measurement of the complex-valued radiation field. This review concentrates on active THz imaging with electronic sources combined with power detectors or coherent receivers - the system class most likely to deliver fast (ideally real-time), cost-effective and deployable solutions for a wide range of industrial applications such as quality control, non-destructive testing, security screening and ranging for situational awareness. Such systems should be deployable on robotic and emerging autonomous platforms. We review the state of the art of compact
semiconductor detector arrays, of imaging modalities ranging from focused-beam raster and frequency-modulated continuous-wave architectures to coherent
Fourier-plane acquisition, and of augmentation techniques such as compressive sensing. Particular
attention is paid to the growing role of artificial intelligence: from convolutional neural networks and physics-informed deep learning for phase
retrieval and image reconstruction, to agentic frameworks for autonomous system design. The bottlenecks of THz imaging - acquisition speed, resolution, contrast and cost - are re-examined in the light of these innovations, and a reference-anchored technology roadmap is derived which projects an order-of-magnitude reduction in the measurement requirements of THz imaging.
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All authors Aparajita Bandyopadhyay, Hui Yuan, Willie J. Padilla, David J. Brady, Hartmut G. Roskos
Instrumentation and Methods for Astrophysics
Wavelength Calibration Accuracy Across the STIS CCD: Pipeline Update and User Guidance
Matilde Mingozzi, Robert Jedrzejewski, Matthew Siebert et al. (+3 more)
We investigate the wavelength calibration accuracy of STIS CCD spectra as a function of detector position, focusing on the E1/E2 pseudo-apertures. Comparison between measured lamp line centroids and laboratory wavelengths shows that, while the standard calstis solution is stable at the detector center, significant offsets are present toward the CCD edges and increase with time. We used a test version of calstis in which the wavelength calibration step employs a row-selected cross-correlation, leading to improved wavelength calibration accuracy for edge extractions. Motivated by these results, we implemented an update to calstis4 that applies a row-selected wavecal procedure to observations taken with the E1/E2 pseudo-apertures, while preserving the standard procedure for nominal extractions. The updated pipeline was then used to reprocess the entire STIS archive in MAST. Validation tests confirm improved agreement between nominal and E1/E2 spectra without significant side effects for more than 97% of the
datasets in the MAST archive. The main exceptions are the majority of G230MB and a few G230LB and G430M
datasets, where the lower signal-to-noise at the CCD edge makes the lamp lines harder to detect and
cosmic-ray residuals can dominate the cross-correlation, leading to incorrect wavelength shifts. A Jupyter Notebook is also provided to enable similar corrections in case the cross-correlation fails, for extractions at positions other than E1/E2, or for multiple extractions along the slit. Finally, we discuss the potential impact of the wavelength calibration accuracy on science results.
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All authors Matilde Mingozzi, Robert Jedrzejewski, Matthew Siebert, Daniel Welty, Sean Lockwood, Joleen Carlberg
Geophysics
A micro-continuum physics-based model for cohesive sediment gravity flows across mudslide, mudflow, and turbidity current regimes
Mitchell D. Jans, Cyprien Soulaine, Judy Q. Yang et al. (+1 more)
Gravity driven sediment flows are responsible for a major portion of sediment redistribution within oceans, reservoirs, and lakes, with important implications in coastal erosion, siltation, carbon burial, and contaminant migration in aquatic systems. Despite the ubiquity of this phenomenon, current mechanistic understanding of sediment
gravity flows (SGFs) remains limited. This knowledge gap is particularly acute in the case of cohesive, fine-grained sediments (i.e., muds) due to the complex properties of the clay
matrix, including low permeability, viscoplastic rheology, and flocculation. In this work, we develop a computational fluid dynamics model that accurately predicts key features of cohesive, clay-rich SGFs based on independent measurements of the relation between sediment solid fraction and rheological yield stress. In particular, the model captures the four primary flow regimes (low density turbidity currents, high density turbidity currents, mudflows, and mudslides) observed in lock-exchange experiments with slurries containing smectite or kaolinite clay. The model is validated through comparison with previous experimental observations of sediment flow morphology, speed, and runout distance. Overall, we demonstrate the ability to predict the influence of intrinsic (particle size, grain density, and rheology) and extrinsic sediment properties (sediment topography and solid fraction) in the development of self-sustaining cohesive SGFs.
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All authors Mitchell D. Jans, Cyprien Soulaine, Judy Q. Yang, Ian C. Bourg
Astrophysics of Galaxies
The Rotation Curve of the Milky Way: State of the Art, the Keplerian Decline Debate, and Implications for Dark Matter
Alessandro Melchiorri and Ruchika
For four decades, the roughly flat rotation curve (RC) of the Milky Way (MW) stood as local evidence for an extended dark matter (DM)
halo.
Gaia DR3 has changed the picture: several analyses now find a velocity decline beyond R \approx 15\kpc, and the most radical interpretation \citep{jiao2023} claims a nearly Keplerian fall-off (\vc \propto R^{-1/2}) that excludes a flat RC at 3\sigma and implies a total dynamical mass of only \sim 2 \times 10^{11}\Msun—three to five times below pre-
Gaia estimates. Taken at face value, this would make the MW exceptional among comparable spirals and challenge both \Lambda-CDM and MOND. It would also alter predictions for direct-detection experiments, although the local DM density is not fixed by virial mass alone. The Keplerian claim rests on the delicate assumptions of axisymmetric Jeans modelling, while
stellar streams, globular clusters, satellite kinematics, and the Local Group timing argument generally favour a substantially heavier
halo, and cosmological simulations reveal potentially substantial biases in Jeans-inferred outer RCs. This review offers a self-contained, pedagogical account of the debate: we derive the full formalism from first principles—the Jeans equations, the asymmetric drift correction, the standard DM
halo and baryonic mass models, the MOND flat-RC prediction, and the timing argument—present an illustrative phenomenological MCMC fit and a Gaussian Process reconstruction of the RC, and critically assess which features of the decline can be regarded as established and which remain open.
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Disordered Systems and Neural Networks · Cross-listed from math.PR
The sharp SAT/UNSAT phase transition in random ellipsoid fitting
Theodor Misiakiewicz and Garrett G. Wen
Let $x_1,\ldots,x_n$ be independent standard Gaussian vectors in $\mathbb{R}^d$. An ellipsoid fit is a
matrix $S \succeq 0$ such that $x_i^\top S x_i =d$ for every $i$, so that all the points lie on the boundary of the centered ellipsoid $\{ x : x^\top S x = d\}$. Saunderson, Parrilo and Willsky conjectured that, as $n,d \to \infty$, this semidefinite feasibility problem undergoes a sharp transition at $n \sim d^2/4$. We prove this
conjecture. If $\lim \sup n/d^2 = \alpha^* <1/4$, then, with probability tending to one, an ellipsoid fit exists; moreover, one can choose $S$ with all
eigenvalues in a fixed interval $[\lambda_- , \lambda_+] \subset (0,\infty)$ depending only on $\alpha^*$. Conversely, if $\lim \inf n/d^2 > 1/4$, then, with probability tending to one, no ellipsoid fit exists, without any spectral restriction. Our proof builds on the Gaussian-equivalence framework developed by Bandeira and Maillard (2025) and closes the two gaps left open in their work: establishing exact fitting and removing the operator-norm constraint. On the satisfiable side, the new ingredients are a head-tail decomposition of the dual vector, exact correction of the sparse head constraints, and a Gaussian comparison principle for the low-influence tail. On the unsatisfiable side, we split a candidate into a low-rank spectral head and a Schatten-3 diffuse bulk, Gaussianize the bulk conditionally on the head, and apply a projected Gordon escape argument. The threshold is governed by the statistical dimension $d(d+1)/4$ of the positive semidefinite cone.
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Astrophysics of Galaxies
Constructing X-ray Spectral Models of Galaxies: Varying Contributions from X-ray Binary Populations with Host Galaxy Properties
Emerson Gehr, Bret D. Lehmer, Antara R. Basu-Zych et al. (+7 more)
Recent work has shown that the emission from X-ray binary (XRB) populations in
galaxies varies with
stellar mass ($M_\star$),
star formation rate (SFR), and
metallicity ($Z$). Such scaling relations are widely used to predict the XRB contributions to
galaxy-integrated X-ray luminosities including studies focused on
dwarf active
galactic nuclei (AGN) and the X-ray radiation field during the epoch of heating in the early ($z \geq 8$) universe. However, as
galaxies approach low SFR and low $Z$, the relatively shallow slope of the XRB luminosity function (XLF) can yield very large
stochastic variations in the total X-ray luminosity expected from the XRB population, for fixed values of $M_\star$, SFR, and $Z$. We have created a procedure to statistically sample any XLF and model total X-ray spectra for XRB populations and their
stochastic uncertainties. We demonstrate the accuracy of this procedure using data for
galaxies ranging from high to low $M_\star$, SFR, and $Z$ and generating X-ray spectral models consistent with Chandra observations. For
galaxies that lie on the
galactic main-sequence, we can relate SFR and $Z$ to $M_\star$ using established $M_\star$-SFR and $M_\star$-$Z$ relations. Applying these relations, we construct main-sequence (MS) XRB spectral models, which provide typical XRB spectral shapes, normalizations, and uncertainties as a function of $M_\star$. The spectral model library associated with this work is available at https://doi.org/10.5281/zenodo.20126734.
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All authors Emerson Gehr, Bret D. Lehmer, Antara R. Basu-Zych, Konstantinos Kovlakas, Vianney Lebouteiller, Erik B. Monson, Izabela Pavel, Chris Richardson, Maxime Varese, Zachary Wilson
Materials Science
Light Polarization Sensitive Transistor Action in the van der Waals ferroelectric 4H-SnS2
Abhishek Bajgain, Rabindra Basnet, Subhashree Chatterjee et al. (+2 more)
Van der Waals (vdW) ferroelectric
semiconductors provide a unique platform for exploring the interplay between spontaneous polarization, electronic transport, ion migration, and photocarrier generation at the nanoscale. Here, we establish a room-temperature ferroelectric state in SnS2 and its sensitivity to structural polytype by directly contrasting the centrosymmetric 2H-phase with the polar 4H-phase. Raman spectroscopy distinguishes the 2H and 4H polymorphs of SnS2 through their characteristic
phonon fingerprints. Piezoresponse force microscopy confirms room-temperature ferroelectricity in the 4H phase, while the 2H phase exhibits no ferroelectric response. The built-in polarization in a three-terminal transistor device of the 4H-SnS2 is modulated significantly by electrostatic gating and on exposure to linear and circularly polarized light. This device reveals polarization-controlled output characteristics with distinct gate-voltage induced hysteretic response and thermally activated carrier transport, confirming p-type semiconducting behavior strongly coupled to ferroelectric polarization. The photoresponse likewise exhibits polarization-assisted carrier separation, sublinear power-law scaling, a nonmonotonic temperature response correlated with the characteristic Raman modes, ferroelectric hysteresis, and a pronounced dependence on the circular and linear polarization states of the incident
laser beam. These results establish 4H-SnS2 as a promising material system for polarization-driven electronic and optoelectronic technologies, including nonvolatile
memory and photoferroelectric functionalities.
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All authors Abhishek Bajgain, Rabindra Basnet, Subhashree Chatterjee, Alexander Samokhvalov, Ramesh C. Budhani
Medical Physics · Cross-listed from cs.CV
Motion Artifact-Aware Self-Supervised Representation Learning for 3D Brain MRI Motion Artifact Reduction
Mojtaba Safari, Shansong Wang, Zach Eidex et al. (+4 more)
Patient motion remains a source of image degradation in
brain MRI, leading to signal loss, blurring, and
geometric distortion that compromise quantitative analysis. Existing deep learning methods for motion correction typically rely on paired clean-corrupted data or k-space acquisitions, which are rarely available in clinical settings. We propose SSRL-MAR, a motion artifact-aware unpaired representation learning framework for motion artifact reduction that requires neither paired training data nor explicit motion labels. SSRL-MAR employed a three-stage training strategy: (1) contrastive learning on 3D patches to extract motion representations by contrasting clean and synthetically corrupted images, (2) a motion artifact-aware synthesis network to generate motion artifacts from clean scans, and (3) a motion artifact-aware generator to restore clean volumes using the learned degrader for self-supervised supervision. On in-silico
dataset, SSRL-MAR achieved PSNR 23.81dB, SSIM 91.55%, and NMSE 0.79%. On in-vivo MR-ART
dataset, the pretrained model reduced motion distortion, and unsupervised domain adaptation further improved anatomical fidelity. Against a source-only supervised model trained on the same simulated pairs, SSRL-MAR improved PSNR by up to 2.0 dB on MR-ART after unsupervised domain adaptation, and remained within 0.25-0.47 dB of an oracle supervised model that requires real paired data unavailable in practice. At the milder motion level, volumetric error in structures such as the corpus callosum and ventricular system decreased by more than 50%, confirming improved neuroanatomical consistency. These results indicate that SSRL-MAR provides a robust and scalable image-domain solution for 3D
brain MRI motion correction, enabling reliable structural quantification in large-scale neuroimaging studies without requiring prospectively acquired pairs or acquisition-specific calibration.
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All authors Mojtaba Safari, Shansong Wang, Zach Eidex, Matthew Goette, Tonghe Wang, Zhen Tian, Xiaofeng Yang
General Relativity and Quantum Cosmology
A parametrized test of general relativity for inspiralling eccentric binaries in LISA
Pankaj Saini, Sylvain Marsat, Lorenz Zwick et al. (+2 more)
The space-based detector
Laser Interferometer Space
Antenna (LISA) will observe inspiralling black hole binaries in the mHz band, many of which may retain orbital eccentricity. In contrast to quasicircular binaries, eccentric systems radiate through multiple orbital harmonics, while relativistic periastron precession introduces a secular phase structure in the waveform. We exploit this structure to develop a parametrized test of general relativity (GR) for eccentric bound orbits. We construct a frequency-domain eccentric waveform model in which a phenomenological deviation parameter $\delta\alpha$ modifies the GR prediction for the conservative azimuthal-to-radial frequency ratio, with $\delta\alpha=0$ corresponding to GR. We consider two parametrizations of this deformation. In the first, $\delta\alpha$ modifies only the explicit precession-dependent sideband structures of the waveform. In the second, the secular precession phase is assigned to the dominant lower-order angular carriers and retained in resummed form. The latter produces a substantially stronger response because the dominant waveform components coherently accumulate the modified phase. We implement both models within lisabeta and perform a
Bayesian analysis including the time- and frequency-dependent LISA response and associated time-delay-interferometry observables. We find that LISA can place stringent constraints on the parametrized deviation. For a binary with chirp mass $3000 M_{\odot}$, initial eccentricity $e_0=0.5$ observed for four years at an SNR of $50$, the second model yields a $90\%$ credible bound of $|\delta\alpha|\lesssim 10^{-4}$. Increasing eccentricity further sharpens the constraints by introducing additional harmonic structure and reducing degeneracies among the binary parameters. The framework developed here is general and can be extended to more complete eccentric waveform models.
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All authors Pankaj Saini, Sylvain Marsat, Lorenz Zwick, János Takátsy, Johan Samsing
Instrumentation and Methods for Astrophysics
CCD Rotation Rates From Regular Dispersion Solution Monitoring
Matilde Mingozzi and Matthew Siebert
It has been previously studied that the STIS CCD exhibits a slow rotation, evident from changes in spectral traces and flat-field
evolution. In this Instrument Science Report, we present an independent spectroscopic analysis of the CCD rotation angle and a comparison with previous studies. We describe the methodology used to derive rotation angles and rates across different gratings and central wavelengths, and report the corresponding median rotation rates over time. The results are broadly consistent within uncertainties with earlier measurements, indicating the CCD rotation has the same impact on all the CCD gratings. We also discuss key assumptions limiting our analysis. These findings contribute to the ongoing monitoring of STIS CCD rotation and its implications for calibration accuracy.
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Astrophysics of Galaxies
The Extended Mapping Obscuration to Reionization with ALMA (Ex-MORA) Survey: A Molecular Gas Line Search
V. Catán, J. González-López, M. Aravena et al. (+9 more)
Current investigations of cold gas in the interstellar medium face selection biases, as optical/near-infrared surveys favor massive, low-obscuration
galaxies and miss gas-rich passive or inefficient
star-forming systems. Overcoming this requires large-volume line surveys selected by molecular gas rather than
stellar luminosity. We present a molecular gas census across $0.5 < z < 5$ using ALMA Band 4 observations from the Extended Mapping of Obscuration to Reionization Survey (Ex-MORA), covering 577 arcmin$^2$. Combining an unbiased search for bright emitters with a targeted search using spectroscopic
redshift priors, we detect 52
galaxies in CO or \ci transitions (two showing two lines). Physical properties were derived via CIGALE with non-parametric
star-formation histories, and gas masses were estimated using
metallicity-dependent conversion factors. The sample is dominated by main-sequence (MS)
galaxies with high
stellar masses (median $\log M_*/\text{M}_{\odot} = 10.83$) and large gas reservoirs ($>10^{10}\,\text{M}_{\odot}$). Gas fraction ($\mu_{\text{gas}}$) increases with
redshift for active populations, though high-
redshift trends are influenced by a gas-rich protocluster at $z \approx 2.4$. Conversely, an overdensity at $z \approx 0.73$ mirrors the field population. Five Green Valley (GV)
galaxies exhibit a $\mu_{\text{gas}}$ peak at
cosmic noon, suggesting
stellar feedback may suppress
star formation by heating gas rather than rapidly depleting it in at least some transitional systems. Resolved kinematics show a prevalence of rotating disks. These results demonstrate that wide-area line searches effectively recover massive gas reservoirs across diverse evolutionary stages
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All authors V. Catán, J. González-López, M. Aravena, A.S. Long, C.M. Casey, D.L. Clements, E. da Cunha, M. Franco, A.M. Koekemoer, A. Man, J. Spilker, E. Treister
Cosmology and Nongalactic Astrophysics
CORN – Chronometers of Relic Nature I: The first estimate of the expansion rate of the Universe using compact relic galaxies
Krzysztof Lisiecki, Nicola Principi Cavaterra, Agnieszka Pollo et al. (+9 more)
Measuring the expansion rate of the Universe is a central challenge in cosmology. Independent and robust methods are essential to validate existing measurements and assess potential systematic effects. We employ the
cosmic chronometer (CC) approach, which uses the differential age
evolution of quiescent
galaxies to measure the Hubble parameter H(z) without assuming an underlying cosmological model. In contrast to previous CC studies, we restrict our analysis to relics – ultra compact massive
galaxies (UCMGs) hosting the oldest
stellar populations – thereby minimising uncertainties related to
star formation history and merger history. We select a sample of 189 relic
galaxies in the
redshift range 0.07< z <0.22 from the E-INSPIRE UCMGs catalogue. Using the D_n4000 spectral index of relic
galaxies and its
redshift evolution, combined with MILES
stellar population synthesis models, we derive the differential age relation required to infer H(z). We account not only for
metallicity effects but also for the impact of alpha-element enhancement, which has not been explicitly propagated into the systematic uncertainty budget of the D_n4000
cosmic chronometer method. We obtain an independent measurement of H(z=0.15) = 85\pm53 km/s/Mpc. The total uncertainty is dominated by statistical limitations. The systematic component is 13% (8.7% when alpha-enrichment is not propagated), among the tightest estimates in current CC studies. We find that alpha-enrichment plays a major role in the systematic error budget, particularly in the high
metallicity regime, and must be properly accounted for in future analyses. We demonstrate the proof of concept that relic
galaxies provide a promising pathway to reduce systematic uncertainties in the CC method. The statistical uncertainties, which dominate the error budget, can be significantly reduced by the increase of data volume expected during the next years.
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All authors Krzysztof Lisiecki, Nicola Principi Cavaterra, Agnieszka Pollo, Chiara Spiniello, Laura Hunt, Charlie Rosen, Marek Biesiada, Darko Donevski, Patryk Matera, Giuliano Lorenzon, Katarzyna Małek, John Mills
History and Philosophy of Physics
Was Schrödinger ever a determinist?
Flavio Del Santo and Nicolas Gisin
Erwin Schrödinger is often portrayed as a reactionary who resisted the indeterminism introduced by
quantum mechanics, but on closer inspection his views on determinism prove to be more complex and more radical.
Instrumentation and Methods for Astrophysics
The eXtreme Wavefront Control Toolkit: High-Contrast Imaging Instrument Control for Ground and Space-Based Coronagraphs
Jared R. Males, Joseph D. Long, Sebastiaan Y. Haffert et al. (+16 more)
We present the eXtreme Wavefront Control Toolkit (XWCTk) instrument control software system developed for the MagAO-X extreme adaptive optics (ExAO) instrument. The XWCTk is built on a foundation of the ImageStreamIO (ISIO) / MILK / CACAO low-latency image processing and high dimensional control tool chain. Instrument control is managed with the Instrument Neutral Distributed Interface (INDI). The application framework provides configuration, logging, and distributed IPC with INDI and low-latency IPC with ISIO. On MagAO-X, every detector is a potential wavefront sensor capable of sending commands to three separate DMs. MagAO-X utilizes a distributed control system, where multiple computers each manage low-latency wavefront control tasks but are capable of coordinated control. Implemented
algorithms include neural networks for nonlinear reconstruction at over 3 kHz. We have incorporated distributed raspberry pis for accelerometer data acquisition with low-latency streaming to the real-time computers for sensor fusion control. A core design principle of the XWCTk is that all data can be saved all the time. This includes full-rate WFS images, DM commands, as well as science data. To facilitate this we have implemented a custom lossless compression system capable of sustaining high data rates to disk. A python interface for scripting and experimentation, as well as a python application framework is provided which can be used for non-real-time tasks. Remote operations (e.g. from Tucson Arizona when the instrument is at LCO in Chile) are routine. The XWCTk is under continuous development for the MagAO-X instrument, and will be adapted for GMagAO-X, the planned first-light ExAO coronagraph for the
Giant Magellan
Telescope. XWCTk is the baseline for a space high contrast imaging instrument, and as such ongoing development is focused on automation for robust operation in flight.
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All authors Jared R. Males, Joseph D. Long, Sebastiaan Y. Haffert, Kyle Van Gorkom, Parker Johnson, Rico Landman, Eden McEwen, Olivier Guyon, Vincent Deo, Miles Lucas, Irina Stefan, Katie Twitchell, Jay Kueny, Joshua Liberman, Adam K. Taras, Adam Schilperoort, Matthijs Mars, Ewan S. Douglas, Laird M. Close
Instrumentation and Methods for Astrophysics
Freezing the speckles: focal plane wavefront sensing with the spatially-clipped self-coherent camera
Joshua Liberman, Sebastiaan Y. Haffert, Jared R. Males et al. (+8 more)
The next generation of Extremely Large
Telescopes (ELTs) and the Habitable Worlds Observatory (HWO) require active speckle suppression to directly image exo-Earths. Focal plane wavefront sensing and control allows us to detect and remove time-varying speckles through measurements of the electric field. Wavefront sensing approaches include pairwise probing (PWP) and the self-coherent camera (SCC). However, the PWP technique is time-consuming, requiring at least 4 images and reducing the speed at which aberrations can be eliminated. The classical SCC modifies a standard coronagraph design, creating a reference electric field that interferes with speckles in the final focal plane, forming Fizeau fringes. However, this design only works over small spectral bandwidths and requires significantly oversized optics, limiting its effectiveness. We demonstrate a new SCC variant, the Spatially-Clipped SCC (SCSCC). The SCSCC utilizes a pinhole placed close to the Lyot stop, reducing the overall beam footprint and boosting the sensor's spectral bandwidth by factors of 3, respectively. A beamsplitter and knife edge downstream of the Lyot stop splits the light into 2 channels: fringed and unfringed, enabling wavefront sensing with a single exposure. Time-varying speckles are frozen in place, making them easy to remove. We present the SCSCC optical design combined with the
photon resolving Hamamatsu Orca-Quest 2 camera. Furthermore, we demonstrate high speed wavefront control with the SCSCC, minimizing speckle intensity by 2x within a 5-11 lambda/D dark hole region on the Comprehensive Adaptive Optics and Coronagraph Test Instrument (CACTI) at the University of Arizona. These lab tests are in preparation for an on-sky demonstration of the SCSCC with the MagAO-X instrument. Our results make the SCSCC a valuable wavefront sensor for upcoming missions, including the
Giant Magellan
Telescope and HWO.
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All authors Joshua Liberman, Sebastiaan Y. Haffert, Jared R. Males, Aditya Khandelwal, Stephanie Rinaldi, Joseph D. Long, Katie M. Twitchell, Jay K. Kueny, Ewan S. Douglas, Lauren Schatz, Jhen Lumbres
High Energy Physics (Experiment)
Search for a resonance in events with four top quarks decaying into two leptons and jets in proton-proton collisions
CMS Collaboration
A search for a heavy resonance in events containing four top
quarks is presented and interpreted in models featuring a new vector, scalar, or pseudoscalar
boson that interacts exclusively with top
quarks.
Proton-
proton collision data collected by the CMS experiment at the CERN LHC at centre-of-mass energies of 13 and 13.6 TeV are analysed, corresponding to integrated luminosities of 138 and 35 fb$^{-1}$, respectively. Events with two
leptons (electrons or
muons) and jets are selected. The mass of the heavy resonance is reconstructed from a pair of jets that are formed using a variable-radius jet clustering
algorithm. A machine-learning approach is used to identify whether these jets originate from top
quarks that decay fully hadronically. The dominant background from misidentified jets is estimated from data as a function of the dijet invariant mass. No significant excess is observed in data. Upper limits at 95% confidence level are set on the resonance production cross section for resonance masses between 500 GeV and 4 TeV, and relative widths ranging from 4 to 50%. In the vector-mediator
benchmark, resonances with 50% relative width are excluded up to masses of 850 GeV, with an expected exclusion limit of 1000 GeV. This is the first dedicated search for these models in the two
lepton channel.
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Quantum Physics · Cross-listed from cs.DS
A Simple Algorithm for Best Separable State
Prashanti Anderson, Samuel B. Hopkins and Amit Rajaraman
We study the best separable state problem (BSS), which asks for the maximum acceptance probability of a
quantum measurement over unentangled states. In classical terms, the goal is to maximize $\langle(x \otimes y), M (x \otimes y)\rangle$ over unit vectors $x,y$ where $0 \preceq M \preceq I$; we call this value $\mathrm{BSS}(M)$. We study $\mathrm{BSS}$ in the "perfect completeness" regime, where given $M$ such that $\mathrm{BSS}(M) = 1$ the goal is to find the best possible solution $x,y$ – this generalizes the problem of finding a rank-one
matrix as close as possible to a given subspace of $\mathbb{R}^{n \times n}$ guaranteed to contain a rank-one
matrix. The strongest known algorithmic guarantees for this problem are: (1) an
algorithm which finds a solution with value $1-\varepsilon$ in time $\exp(\sqrt{n} (\log n)^{O(1)} / \varepsilon^2)$, due to Barak, Kothari, and Steurer, and (2) an
algorithm which finds a solution with value $q/n$ in time roughly $n^{O(q)}$, due to Bhattiprolu, Ghosh, Guruswami, Lee, and Tulsiani. We give a much simpler approach to rounding the SoS relaxation, generalizing the canonical "global correlation rounding" technique, and obtain a better running time. Given $M$ with $\mathrm{BSS}(M) = 1$, our
algorithm finds a solution with value $1-\epsilon$ in time $n^{O(\sqrt{n/\varepsilon})}$, and a solution of value $q/n$ in time $n^{O(\sqrt q)}$. Using the same techniques, we prove a new variant of the "pinning lemma", a measure-decomposition
theorem widely used in LP/SDP rounding, high-dimensional probability, and statistical physics, which we believe is of independent interest.
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Optics
Practical Evaluation of FFT-Based Thickness Extraction for Thick-Film Reflectometry
Zimu Zhou, Enrique A. Lopez-Guerra, Michael Kwan et al. (+1 more)
Fast
Fourier transform (FFT) is widely used for thick-film reflectometry because of its simplicity and computational efficiency. However, its performance under practical thick-film measurement conditions has received limited experimental evaluation. In this work, FFT, Linearized Reflectance Zero-Crossing (LRZ), and optical model fitting were compared using reflectometry measurements from a nominal 52 {\mu}m dielectric film acquired on a production wafer, with White-Light Interferometry (WLI) serving as an independent reference. Although FFT exhibited excellent repeatability, it showed systematic deviation from WLI (RMSE = 0.62 {\mu}m), whereas LRZ significantly improved accuracy (RMSE = 0.20 {\mu}m). Simulations and theoretical analysis indicate that the observed systematic deviation is consistent with spectral leakage caused by finite measurement windows and non-integer fringe periodicity. These results demonstrate that excellent repeatability does not necessarily imply high accuracy and highlight the advantages of zero-crossing-based approaches for thick-film thickness metrology.
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All authors Zimu Zhou, Enrique A. Lopez-Guerra, Michael Kwan, Chester Chien
Instrumentation and Detectors
Machine learning methods for spectroscopic information recovery under ultrafast photon pileup
Jayson R. Vavrek, Thomas D. MacDonald and Yue Shi Lai
We present methods for recovering spectroscopic information from multiple concurrent
photon interactions that would normally be lost due to pulse pileup. In particular, we focus on machine learning methods to recover information based on spatial (rather than temporal) energy deposition patterns in position-sensitive detectors. We construct two representative problems, namely (1) recovering the fraction of total energy deposition stemming from a monoenergetic signal vs. a smooth background; and (2) recovering the signal multiplicity, i.e., the number of interacting
photons, in a pure-source-term example. In the signal fraction recovery problem, we use 3D convolutional neural networks (CNNs), fully-connected neural networks (FCNNs), a network based on the PointNet++ architecture, and two non-machine-learning methods to estimate the signal fraction in synthetic data when up to 20 total piled-up
photons are present. The CNN, FCNN, and PointNet++ models reconstruct the signal energy deposition fractions with root mean square errors (RMSEs) of $14.5\%$, $18.8\%$, and $16.8\%$ given training
datasets that fit in-core, while the classical methods perform poorly and will not improve with additional training data. In the multiplicity recovery problem, we demonstrate that, when trained with synthetically-piled-up real Cs-137 data, the 3D CNN architecture can recover the multiplicity with sub-
photon RMSE, outperforming non-ML baselines. These methods can be adapted to future, more specific
photon active interrogation applications, helping to re-enable spectroscopic analyses in those domains.
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Solar and Stellar Astrophysics
A Pre-Main Sequence Binary Viewed Through its Circumbinary Disk: A New Phase for KH 15D
Catrina M. Hamilton, Adi B. Chacko, George A. Carson et al. (+16 more)
The binary T Tauri system, KH 15D, is poised to provide unprecedented detail of gas and ices located between $\sim$3-5 AU of its circumbinary disk over the next few years. We analyze for the first time a complete set of ground-based time series photometry of the KH 15D system for which the 2022 October - 2025 April data have never been presented. By combining the latest $I$-band data with historical measurements, we show that the era of large amplitude photometric variability has ended. We define a revised photometric period of $P$ = 48.365 $\pm$ 0.005 days, which accurately phases data over a time span of seventy-five years. We adopt magnitudes and colors for the
stars that define the epochs when either
star A (1995-2008) or
star B (2010-2012) is the primary source of the out-of-eclipse brightness of the system. We determine for the first time the effective optical depth for the system between 2002 and 2025 assuming gray extinction. The current out-of-eclipse system color is consistent with a combination of the light from both
stars, supporting the previously suggested model in which the trailing edge of the circumbinary disk is more transparent than the leading edge. We continue to see evidence for “clumps” and variable transparency along ingress and egress when the
stars are probing the occulting material and suggest that observations made during these phases should permit studies of the physical and chemical nature of the
planet-forming zone with the circumbinary disk.
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All authors Catrina M. Hamilton, Adi B. Chacko, George A. Carson, Aidan J. Pidgeon, C. Nicole Foley, Hillel Finder, Kyle Gimmy, Aleezah Ali, William Herbst, Dirk Froebrich, Brian A. Skiff, Bart Staels, Shawn Dvorak, Jochen Eislöffel, Teryn Huff, Gavin Frueh, Abigail Mead, Lia M. Gilmore, Robert J. Boyle