Medical Physics
Circulating Lymphocytes Preservation in Lung Cancer Stereotactic Body Radiation Therapy with Ultra-Fast Proton Delivery Using Modularized Pin Ridge Filters
Duncan Bohannon, Ahmal Jawad Zafar, Sibo Tian et al. (+9 more)
Purpose: Radiation-induced lymphopenia is an increasingly recognized toxicity in lung radiotherapy and has been linked to radiation exposure to circulating lymphocytes (CL). In intensity-modulated
proton therapy (IMPT), prolonged pencil beam scanning (PBS) delivery may increase CL dose. We recently developed a patient-specific pin ridge filter (pRF) framework that enables ultra-fast
proton delivery with a single beam energy. This study evaluated whether pRF-based lung stereotactic body radiotherapy (SBRT) plans delivered at conventional (pRFCONV) and FLASH dose rates (pRFFLASH) improve immune sparing using time-resolved blood dose accumulation and CL survival modeling. Methods: pRF plans were created for 10 lung SBRT patients previously treated with IMPT. PBS delivery simulations modeled spot delivery, scanning, and energy switching. Blood dose-volume histograms (bDVHs) were calculated with the hematological dose framework. CL survival fractions (SF) were estimated from bDVHs with saturation and linear-quadratic models derived from in-vitro survival data for CD4/CD8 CL. Results: Compared with IMPT, pRFCONV/pRFFLASH plans reduced delivery time (mean reductions: 85.3/99.9%) and irradiated blood volume per fraction (mean reductions: 52.9/81.3%). pRFCONV/pRFFLASH plans reduced blood V5cGy by 26.4/39.4%, and V50cGy by 4.5/6.9%, respectively. pRF plans improved modeled CL survival across all models and subpopulations. Unstimulated CD4/CD8 CL had the largest SF differences, for which mean saturation-model SF improved by 7.9/8.6% for pRFCONV (p=0.03/0.02) and 9.6/10.4% for pRFFLASH (p=0.02/0.01), respectively. Conclusion: pRF plans improved modeled CL survival by significantly shortening delivery time and reducing irradiation of circulating blood. Our findings suggest that pRF's ultra-fast delivery may provide a practical strategy for immune sparing in
proton lung SBRT.
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All authors Duncan Bohannon, Ahmal Jawad Zafar, Sibo Tian, Williams Stokes, Zachary S. Buchwald, Sunil W. Dutta, William A. LePain, Zachary Diamond, Anees Dhabaan, Hania Al-Hallaq, Xiaofeng Yang, Jun Zhou
Earth and Planetary Astrophysics
The JDISC Survey: Inner Disk Chemistry of Class I/FS Disks and Tentative Evidence for Early Pebble Drift
Ke Zhang, Andrea Banzatti, Colette Salyk et al. (+22 more)
We present the first chemical survey of Class I and Flat-Spectrum (I/FS) disks using JWST MIRI/MRS, targeting sixteen sources in the Ophiuchus
star-forming region. Through empirical line luminosity measurements and multi-component slab modeling, we characterize the molecular reservoir of these young systems and compare them to twelve Class II disks of similar
stellar mass. Water, HCN, C$_2$H$_2$, and CO$_2$ are frequently detected in I/FS sources with inclinations $i < 70^{\circ}$, whereas edge-on systems show significantly suppressed emission. Compared to Class II disks, I/FS sources show suggestive—though not yet statistically significant—evidence for elevated cold water ($\sim$200\,K) mass and lower CO$_2$ excitation temperatures. Statistical analyses identify
accretion luminosity as the primary correlate of molecular mass across both evolutionary stages. Once this dependence is removed, cold water and CO$_2$ masses anti-correlate with mm-
dust disk radius, while hot water remains insensitive to disk size. These patterns are qualitatively consistent with pebble drift models that predict early water enrichment followed by delayed CO$_2$ delivery, suggesting an evolutionary progression from molecular-poor Class 0 sources, through water-rich Class I/FS disks, to Class II disks with reduced cold water excess. This work provides an initial evolutionary framework for disk chemistry that requires larger, multi-region samples to confirm.
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All authors Ke Zhang, Andrea Banzatti, Colette Salyk, Abygail Waggoner, Klaus Pontoppidan, María José Colmenares, Ilaria Pascucci, Lucas A. Cieza, Miguel Vioque, Paola Pinilla, Geoffrey A. Blake, Joan Najita, Joe Williams, Sebastiaan Krijt, Till Kaeufer, Jane Huang, Feng Long, Chengyan Xie, Minjae Kim, Eshan Raul, Dary A. Ruíz-Rodríguez, Nicole Arulanantham, Benoît Tabone, Mayank Narang, Karina Mauco
Astrophysics of Galaxies
The role of filaments in the large-scale conformity signal
Daniela Palma, Ivan Lacerna, Noelia Pérez et al. (+8 more)
We investigate the large-scale conformity signal and its connection with the large-scale structure, focusing on low-mass central
galaxies, after excluding
galaxies that were satellites in the past. We measure the signal across different environments identified with the DisPerSE
algorithm, including group outskirts, cluster outskirts, filaments, filament outskirts, and other environments (voids and walls) in order to assess how each population contributes to the large-scale conformity signal. We use the
galaxy catalogs from the IllustrisTNG300 simulation and the semi-analytic model MDPL2-SAG. In SAG,
galaxies embedded in filamentary regions emerge as the primary contributors to the large-scale conformity signal, closely reproducing its overall shape and amplitude. In TNG300,
galaxies located in filamentary regions also exhibit a coherent, albeit weaker, conformity signal once
galaxies that were satellites in the past are excluded. We also examine whether the signal depends on the adopted filament definition. We find no substantial differences when varying the filament thickness or considering
galaxies in overlapping regions. Instead, the signal remains strong and largely insensitive to these differences. We then investigate the dependence of the conformity signal on filament linear density, length, and mass. The signal is enhanced in high-linear density, short, and high-mass filaments, but remains present in low-linear density, long, and low-mass filaments, although with a slightly lower amplitude. Finally, we find that low-mass central
galaxies located in close proximity to interacting massive systems show an amplified conformity signal extending up to 4 Mpc/h. Overall, our results indicate that filamentary regions, and the
tidal forces from neighboring massive systems play a fundamental role in shaping the large-scale conformity signal.
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All authors Daniela Palma, Ivan Lacerna, Noelia Pérez, Luis Pereyra, Antonio D. Montero-Dorta, Constanza A. Soto-Suárez, Laerte Sodré Jr., M. Celeste Artale, Amrutha Belwadi, Facundo Rodriguez, Nelvy Choque-Challapa
Solar and Stellar Astrophysics
1000 cataclysmic variables identified from DESI spectroscopy
K. Inight, B. T. Gänsicke, A. Aungwerojwit et al. (+41 more)
Most cataclysmic variables (CVs) are discovered when they have an outburst generating an inherent selection bias against CVs that rarely, or never, outburst. CVs discovered by virtue of their spectroscopic characteristics are particularly valuable to offset this bias and we have used an established machine-learning technique to assist in searching 98 966 000 spectra obtained by the Dark Energy Spectroscopic Survey (DESI) to find such CVs. DESI observations are much deeper than previous spectroscopic surveys and we have identified 1029 CVs, 221 of which are new including ten of the AM CVn subtype. We have spectroscopically confirmed 441 CV candidates and obtained 84 new or improved orbital periods. We present revised space density estimates based upon this new data. We have also added ten more to the eight known examples of an intriguing class of CVs which exhibit peculiar changes in
accretion.
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All authors K. Inight, B. T. Gänsicke, A. Aungwerojwit, P. Izquierdo, C. J. Manser, A. D. Myers, A. Swan, J. R. Thorstensen, J. Aguilar, S. Ahlen, D. Bianchi, D. Brooks, T. Claybaugh, A. de la Macorra, Biprateep Dey, P. Doel, A. Font-Ribera, J. E. Forero-Romero, Satya Gontcho A Gontcho, G. Gutierrez, J. Guy, R. Joyce, S. Juneau, S. E. Koposov, A. Kremin, M. Landriau, L. Le Guillou, A. Meisner, R. Miquel, J. Moustakas, J. Najita, I. Pérez-Ràfols, W. J. Percival, F. Prada, G. Rossi, E. Sanchez, D. Schlegel, M. Schubnell, H. Seo, J. Silber, G. Tarlé, B. A. Weaver, R. Zhou, H. Zou
Astrophysics of Galaxies
Unsupervised selection and characterisation of little red dots in JWST surveys with manifold learning
Michele Ginolfi, Filippo Mannucci, Alessandro Marconi et al. (+9 more)
Little red dots (LRDs) are compact, red sources discovered at high
redshifts by JWST, and their physical nature and selection function remain a topic of debate. Here, we investigate whether an unsupervised machine-learning approach applied to multi-band photometry has the capacity to identify LRD-like objects, along with other populations, without relying on predefined colour-cuts. Using UMAP, a
manifold-learning (dimensionality-reduction) method, we placed ~242,000 isolated, well-measured sources from the ASTRODEEP-JWST catalogue on a 2D map, where objects with similar broadband colours, morphology, and photometric
redshift lie close together. We then used spectroscopically confirmed LRDs to identify where LRD-like objects lie within this map. We compared the resulting areas with published colour cuts and validated our data-driven selection against archival NIRSpec spectra from the DJA. We find that the spectroscopically selected LRDs are concentrated in two well-defined regions with no colour-cut imposed, tracing populations that differ mainly in
redshift; a difference that is imprinted on their broadband colours. The main region reaches a purity of ~0.78 at ~0.82 completeness on the spectroscopically classified subset. This result is competitive with (or cleaner than) literature colour-cuts, and yields ~100 additional candidates. We also tested the method as a general tool for population discovery: the
manifold recovers the locations of brown
dwarfs and broad-line active
galactic nuclei with no explicit criterion and isolates rare pathological outliers. Overall, unsupervised
manifolds, anchored by sparse high-confidence spectroscopic labels, provide an efficient, assumption-light framework for characterising populations, comparing selection methods on a common basis, and discovering rare objects in large photometric
datasets.
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All authors Michele Ginolfi, Filippo Mannucci, Alessandro Marconi, Francesco D'Eugenio, Giacomo Venturi, Francesco Belfiore, Giovanni Cresci, Caterina Bracci, Stefano Carniani, Alessandra Cozzi, Roberto Maiolino, Guido Risaliti
Astrophysics of Galaxies
Reionization driven by the few: the ionizing budget of galaxies at z=5-10 from JWST/NIRSpec
Emma Giovinazzo, Pascal A. Oesch, Anne Verhamme et al. (+5 more)
The sources responsible for the Epoch of Reionization (EoR), the last major phase transition of the Universe, remain highly elusive. While JWST has begun to illuminate the properties of early
galaxies, the direct detection of their ionizing
photons is virtually impossible due to the neutral intergalactic medium (IGM) at z>6. A direct estimate of the escape fraction of ionizing
photons (fesc) is thus not possible. However, the escape fraction is encoded in spectral features that trace a low opacity to ionizing
photons, namely the reduction of nebular emission with increasing fesc. Here, we exploit the large archive of JWST/NIRSpec spectra at 5<z<10 from the DAWN JWST Archive to provide new constraints on the ionizing emissivity of EoR
galaxies and on the timeline of reionization. Through detailed spectral fitting of 1428
galaxies with a picket-fence model for the escape of ionizing
photons, we derive posteriors of fesc together with the effective ionizing output. This approach yields the escaping ionizing output of each
galaxy while bypassing the usual decomposition into the ionizing
photon production efficiency and fesc. Combining these measurements with UV luminosity functions (LFs), we derive the hydrogen ionizing LFs, resulting in an observationally-derived ionizing
photon budget at 5<z<15, integrated down to MUV=-13. Under standard assumptions, our budget yields an
evolution of the IGM neutral fraction consistent with independent probes, with reionization ending at z~5.8. Given the evolving shape of the ionizing LF, bright sources (MUV ~ -20) dominate the
cosmic ionizing emissivity nion at lower
redshift (z=5-6), whereas at z>6 faint
galaxies (MUV > -18) contribute roughly equally. Remarkably, a mere ~20% of sources, those with fesc>10%, produce ~87% of the ionizing
photons. Overall, our results support a picture in which a few strongly leaking
galaxies drive most of reionization.
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All authors Emma Giovinazzo, Pascal A. Oesch, Anne Verhamme, Romain A. Meyer, Callum Witten, John Chisholm, Rui Marques-Chaves, Charlotte Simmonds
Strongly Correlated Electrons
New class of exactly flat topological bands - compact localised states protected by local graph topology
Tamaghna Hazra
Strongly correlated
quantum matter is fundamentally defined by the tension between non-commuting
quantum operators.
Hamiltonians exhibiting macroscopic degeneracies are of general interest in this field because they imply an infinite susceptibility to any non-commuting perturbation. In moiré
heterostructures, engineering such extensive degeneracies in the kinetic
Hamiltonian creates a fertile garden for exotic strongly correlated phases of matter to emerge from the resulting flat bands. Here, we introduce a prescription to construct an infinite family of exact flat band
Hamiltonians supported on the faces of arbitrary graphs. We demonstrate this
algorithm on the faces of four Bravais
lattices. Using a discrete graph generalization of the Atiyah-Singer index
theorem, we prove that the extensive degeneracies of such face-graph
Hamiltonians are protected by the local
topology of the face-graph connectivity. The resulting macroscopic null spaces yield compact localised states that remain localised over time due to frustration in hopping pathways. We discuss the broad implications of such non-dispersing
quantum modes in diverse settings, from arrested dynamics in
quantum networks and
quantum machine learning
algorithms to Majorana-free topological
quantum computation.
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Medical Physics
Agentic Autoresearch for CT Reconstruction
Andreas Maier, Lucas Kachelriess, Siming Bayer et al. (+4 more)
Comparing CT reconstruction methods fairly is labor-intensive and largely manual, and many
benchmarks use idealized data. We ask whether a large
language model (LLM)
agent can do the labor of reconstruction research on its own, and whether a ranking measured on ideal data predicts behavior under realistic noise. We built an agentic loop: the
agent edits a solver, runs a short cluster job, reads one frozen metric, and revises. The metric is a calibrated headroom score against the FBP baseline, inside the field of view; every method shares the same differentiable fan-beam projector. We benchmarked 26 methods on Mayo low-dose CT (noise-limited) and a 128-view sparse-view breast task from the noiseless DL-Sparse-View Challenge, with validation-selected iterations scored on a held-out test set. Every trained breast model was then re-scored on noisy inputs (I_0 = 10^5
photons) without retraining, and separately retrained on matched noise. The
agent independently implemented, tuned, and benchmarked all 26 methods, and recombined them into a compact solver of 969 parameters that ties the top Mayo tier at the 1% level using 0.4% of the champion's parameters. Benchmarking gives a tier of statistically indistinguishable top methods, not one winner. Mild input noise nearly inverts the breast ranking: the noiseless champion (a supervised image denoiser, hr 0.89) collapses to 0.00, while a learned primal-dual method rises to champion (0.72 to 0.93). An ideal-data leaderboard therefore does not predict robustness. The inversion is a transfer effect, not a permanent deficit: retraining on matched noise restores much of the clean ranking (Spearman rho 0.04 to 0.61). Noise is only the easiest confounder in an open-ended set (beam hardening, scatter, anatomy, disease), so no single-factor challenge certifies generality.
Benchmarks should model a broad spectrum of realistic factors at once.
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All authors Andreas Maier, Lucas Kachelriess, Siming Bayer, Yixing Huang, Yan Xia, Amber Simpson, Moritz Zaiss
Solar and Stellar Astrophysics
BOSS-CLAM: Utilizing a Constrained Linear Absorption Model to Infer Stellar Parameters from BOSS Spectra
Ilija Medan, Andrew R. Casey, Alexander P. Ji et al. (+13 more)
Large spectroscopic surveys require robust pipelines capable of inferring
stellar parameters over a wide range of the Hertzsprung-Russell (HR) diagram from data of varying quality. SDSS-V is one such survey, where the data from the lower-resolution, optical BOSS spectrograph will provide a large
dataset covering a wide range of
Galactic stellar populations. To better analyze these data, we present BOSS-CLAM, a generative, forward modeling pipeline for inferring effective temperature ($T_\mathrm{eff}$), surface
gravity ($\log g$),
metallicity ($[\mathrm{Fe/H}]$), and $\alpha-$abundance ($[\alpha/\mathrm{M}]$) from continuum-normalized BOSS spectra. BOSS-CLAM maps
stellar labels to Non-negative
Matrix Factorization (NMF) basis vector weights via a
polynomial mapping jointly optimized with the spectral decomposition, which provides a more flexible framework for working with the lower-resolution BOSS data. Additionally, training labels are drawn from four complementary sources (ASPCAP, BOSS-MINESweeper, wide binaries, and a hot
star validation sample), which enables coverage from cool M
dwarfs through hot OB
stars, and across a wide range of
metallicity. We infer parameters for 1,708,214 BOSS spectra, with a recommended clean catalog of 915,514 sources. Validation against open and globular clusters demonstrates homogeneous, accurate abundances across a wide range of
metallicity. Wide binary tests yield abundance uncertainties of $\sigma_{[\mathrm{Fe/H}]} \approx 0.15$ dex and $\sigma_{[\alpha/\mathrm{M}]} \approx 0.06$ dex at SNR = 10. Finally, we demonstrate that the BOSS-CLAM catalog recovers known chemical structure of the Milky Way disk and is well-suited for
Galactic archaeology, chemical tagging, and
stellar population modeling. The pipeline, trained model, and catalog are publicly released as part of SDSS-V DR20.
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All authors Ilija Medan, Andrew R. Casey, Alexander P. Ji, Jonah M. Otto, Kayvon Sharifi, Zachary Way, Madeleine McKenzie, Natalie R. Myers, Keivan G. Stassun, Peter J. Smith, Andrew Tkachenko, Vedant Chandra, Michael R. Blanton, Peter M. Frinchaboy, Guy S. Stringfellow, Sean Morrison
Earth and Planetary Astrophysics
SCoRE: the Surface Composition of Rocky Exoplanets
Leon Sereinig and Oliver Herbort
Context. The crust composition of rocky
exoplanets with a substantial atmosphere can not be observed directly. However, recent developments are starting to allow for the observation and characterisation of their atmospheres. Understanding the link between atmospheres and crusts could allow for constraints on the crusts' composition based on atmospheric observations. Aims. We aim to understand the link between the thermal stability of specific condensates and atmospheric compositions. This allows constraints on the mineralogical composition of the surface by potentially observable atmospheric features. In order to achieve this, a grid study of atmospheric and crustal compositions is conducted. Methods. We use a diverse range of total element abundances inspired by various rock compositions as the compositional base for our crust-atmosphere models, for which thermo-chemical and phase
equilibrium is assumed. In this work, we investigate a temperature range of 500 K to 1000 K and a surface pressure of 1 bar. The resulting atmospheric compositions are classified using atmospheric types based on the most abundant gas-phase elements C, H, N, O, and S. Results. Some of the changes in surface mineralogy coincide with changes in atmospheric type, independent of the given total elemental abundances. In total, a link has been revealed between 23 thermally stable minerals and their corresponding atmospheric types, which is independent of the ratio of the refractory elements present. Especially, the sulphur chemistry of the minerals and the average iron oxidation state can be constrained by the corresponding atmospheric type.
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Quantum Physics
Practical advantage beyond the quadratic speedup limit with fully-quantum walks
Massimiliano Incudini and Guglielmo Mazzola
We introduce a new class of fully-
quantum Metropolis walks in which both the proposal and acceptance steps are intrinsically
quantum. Unlike standard
quantum walks obtained by quantizing classically efficient Markov chains, our
algorithm employs
Hamiltonian simulation as a
quantum-native proposal mechanism, enlarging the class of
quantum walks beyond classical counterparts. We target the problem of sampling from the low-temperature Gibbs distribution of classical dense Ising models, within a fixed error in total variation distance. This approach achieves about a cubic
polynomial asymptotic advantage over previous
quantum-walks, resulting in a total sixth-degree
polynomial queries speedup compared to the best classical walk. This shows that speedups beyond the widely assumed quadratic limit are possible within the
quantum walk formalism. We perform a complete fault-tolerant compilation of all algorithmic primitives and
benchmark against CPU, GPU, and FPGA implementations of the best classical Markov chain. Under identical hardware assumptions, the resulting advantage runtime crossover is reduced from approximately $10^3$ years for conventional
quantum walks to less than one day. These results identify fully-
quantum Markov chains as a promising route toward practical
quantum advantage.
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High Energy Physics (Phenomenology)
$\texttt{SNuDD}$: Solar Neutrinos for Direct Detection
Dorian W. P. Amaral, David Cerdeño, Andrew Cheek et al. (+2 more)
We introduce
Solar Neutrinos for Direct Detection ($\texttt{SNuDD}$): an open-source Python package that enables the computation of the
solar neutrino rate spectrum at direct detection experiments. $\texttt{SNuDD}$ can be used to determine the differential rate for both
nuclear and electron
recoils within the Standard Model and in the presence of beyond Standard Model physics effects, such as those arising from neutral-current non-standard interactions (NSI). The package accounts for matter effects during
neutrino propagation through both the Sun and the Earth and for modifications to the scattering cross sections at the interaction site. We employ $\texttt{SNuDD}$ to place new limits on the effective NSI couplings using results from the xenon-based direct detection experiments LZ, XENONnT, and PandaX-4T, and we project the sensitivity of a future xenon detector based on the planned XLZD and PandaX-xT observatories. We find that current direct detection experiments are rapidly approaching sensitivities comparable to those of dedicated
neutrino experiments and that future xenon detectors can provide leading constraints. We recommend that $\texttt{SNuDD}$ be used to combine incoming direct detection data with those from
neutrino experiments in future global fits, placing direct detection within the broader landscape of
neutrino physics.
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All authors Dorian W. P. Amaral, David Cerdeño, Andrew Cheek, Valeria Costa, Patrick Foldenauer
Cosmology and Nongalactic Astrophysics
Relativistic Chiral MHD with application to the early Universe
Deepen Lark and Jennifer Schober
We present a systematic derivation of the equations of relativistic
chiral magnetohydrodynamics (MHD) for a
plasma of charged
fermions in an expanding universe. Through a combination of a coordinate transformation and a rescaling of the dynamical variables, we bring the full system to the same form as in the Minkowski metric, with the Hubble expansion surviving only in the chirality-flipping rate and the kinematic viscosity. Retaining all four contributions to both the electric and the axial current yields terms absent from standard
chiral MHD: charge-density corrections to the
evolution equations for the chemical potentials, and an electric current proportional to the charge chemical potential $\mu$ and the bulk velocity. The latter is mandated by current conservation, requires no chirality imbalance, and drives the charge-flow instability studied in a follow-up paper. For the radiation-dominated era, we evaluate all the coefficients in physical units and use them to estimate the
magnetic Reynolds number, the attainable
magnetic field strength, and the minimum temperature at which the
chiral dynamo can operate. The resulting equations are cast in a form ready for direct numerical implementation.
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Cosmology and Nongalactic Astrophysics
A charge-flow instability in plasmas with charge fluctuations
Deepen Garg and Jennifer Schober
We present a linear instability in magnetized
plasmas with charge fluctuations. It is driven by an electric current proportional to the charge chemical potential $\mu$ and the bulk velocity. This charge-flow (C-flow) instability has hitherto not been considered in standard magnetohydrodynamics or its
chiral extensions. We derive its dispersion relation and maximum growth rate, and confirm them with direct numerical simulations. We also show that the C-flow instability persists even for zero-mean fluctuations of $\mu$, vanishing resistivity, and a
magnetic Prandtl number of unity.
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Astrophysics of Galaxies
Charting the Galactic Underworld I: Comprehensive simulations of the kinematics, rates, and demographics of Milky Way black holes
Tom Wagg, Katelyn Breivik, Adrian M. Price-Whelan et al. (+3 more)
With upcoming data from Roman,
Gaia DR4, and spectroscopic surveys, we will soon have an unprecedented
dataset of Milky Way black holes (BHs) to constrain their formation and
evolution. To prepare, we simulate the intrinsic population of Milky Way BHs with cogsworth, self-consistently accounting for their binary
evolution and trajectories through the
Galactic potential. We report the rate, demographics, and kinematics of these BHs, and their sensitivity to 32 variations in binary
evolution,
supernova physics, and
Galactic potentials. In the fiducial model, ~$1.7 \times 10^8$ BHs have formed in the Milky Way (though this total spans an order of magnitude across our variations), where the vast majority (~91%) are currently isolated and ~3% have escaped the
Galaxy. Most of the ~$10^7$ BHs in binaries have another BH or a white
dwarf companion, but ~$10^5$ retain a luminous
stellar companion. BHs are distributed more diffusely than visible
stars, with a scale height around ~$2.5\times$ larger. BH masses correlate with present-day location: the most massive BHs are preferentially close to the
Galactic plane. This correlation is especially strong for BH-
star binaries, which separate into tight, low-mass post-common-envelope systems and wide, high-mass non-interacting ones. The BH mass distribution and kinematics are highly sensitive to the remnant mass prescription and natal kick model, so observations could constrain explodability criteria and BH kicks. Accounting for the time-
evolution of the
Galactic potential more than doubles the escape fraction and increases the bound population's scale height by ~20%, whilst neglecting binary interactions overestimates it by 30%.
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All authors Tom Wagg, Katelyn Breivik, Adrian M. Price-Whelan, Mathieu Renzo, Julianne J. Dalcanton, Natasha S. Abrams
High Energy Physics (Phenomenology)
Agentic Re-Casting using Agentic Re-Simulations
Sascha Diefenbacher, Tilman Plehn, Daniel Schiller et al. (+1 more)
Analysis re-casting at the LHC is highly standardized and nevertheless requires resources, time, and physics input. Building on the new MadAgents.v3, we show how a global SFitter analysis can be updated by an agentic system with a physicist in the loop. The agentic interface allows us to make the advanced SFitter methodology available to a wider audience. All physical and technical aspects of this agentic re-casting study can be trivially generalized beyond SFitter.
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All authors Sascha Diefenbacher, Tilman Plehn, Daniel Schiller, Nikita Schmal
Astrophysics of Galaxies
Speeding up Gravitational Lens Mass Models with Machine Learning: Applications in X-ray Astronomy
Alex Ostridge, Rafael Martínez-Galarza, Júlia M. Sisk-Reynés et al. (+2 more)
Multi-wavelength observations of quadruply lensed
quasars constitute a powerful probe of cosmology, dark matter substructure along the line of sight, and the structure of X-ray emitting regions in high-
redshift quasars. These investigations are conditional on acquiring an accurate model for the surface mass density of matter
lensing these
quasars. We propose a simulation-based machine learning method to accelerate parameter inference in real quadruply lensed systems by several orders of magnitude. We simulate a grid of quadruply lensed sources with Singular Isothermal Ellipsoid (SIE) lenses and use the projected positions of the four lensed images to train two fully connected neural networks that predict the mass parameter and ellipticity. For a large fraction of simulated systems, the neural network-initialised mass models converge in time-scales of a few minutes and recover the source position at the <0.”005 level for a broad range of lens masses and ellipticities. We apply our neural networks to seven quadruply lensed
quasars, lensed by isolated
galaxies or a
galaxy-perturber pair, which have archival Chandra observations. The final optimised mass models for each
quasar predict the observed lensed image positions in
Gaia Data Release 3. These mass models enable the caustic method, which locates the X-ray-to-optical emission regions to milliarcsecond precision in these otherwise unresolvable systems, improving the effective angular resolution of Chandra at high-z by up to two orders of magnitude. Our approach accelerates this mass modelling by supplying informed initial parameters, enabling application to the many new quadruply lensed systems expected from forthcoming surveys.
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All authors Alex Ostridge, Rafael Martínez-Galarza, Júlia M. Sisk-Reynés, Daniel A. Schwartz, Anna Barnacka
Quantum Physics
Wigner negativity and stellar rank for SU(1,1) states
A. B. Klimov, A. Muñoz, G. Leuchs et al. (+2 more)
Quasiprobability distributions for systems endowed with SU(1,1) dynamical
symmetry have received surprisingly little
attention, despite the central role of this
symmetry in two-
photon physics, squeezed states, and nonlinear interferometry. Here, we fill this gap by constructing a full covariant family of $s$-ordered quasiprobability distributions defined on the two-sheeted hyperboloid, or equivalently, on the Poincaré unit disk via stereographic projection. A key result is that the Wigner function is strictly positive for all Perelomov SU(1,1) coherent states, in sharp contrast to the SU(2) case. This positivity endows Wigner negativity with an unambiguous operational meaning: any negative volume is a direct signature of genuinely
quantum behavior. We further examine the
stellar rank of SU(1,1) states, defined through the zeros of the Husimi $Q$-function, and show how it compares with Wigner negativity as a geometry-adapted witness of nonclassicality in this setting. We further introduce a hierarchy of generalized multipoles through a harmonic expansion of the density operator on the hyperboloid, providing a complementary framework for probing quantumness. This offers a comprehensive toolkit for characterizing and quantifying
quantum resources in SU(1,1) systems.
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All authors A. B. Klimov, A. Muñoz, G. Leuchs, J.-P. Gazeau, L. L. Sanchez-Soto
High Energy Physics (Phenomenology)
Axion isocurvature and the model-building problem of low-scale inflation
Sarunas Verner
The pre-inflationary QCD
axion is often said to require low-scale inflation. We derive a general isocurvature bound for a light
axion with a scale-invariant spectrum, treating its inflationary normalization $f_I$ independently of the late-time decay constant $f_a$ and allowing for an arbitrary
axion dark matter fraction, nontrivial perturbation transfer, and the full anharmonic abundance response. In the minimal
benchmark, where
axions constitute all of the dark matter, $f_I=f_a\leq M_{\rm Pl}$, and the angular perturbation is conserved, the least restrictive CMB limit considered gives the 95% C.L. upper bound $H_I<1.25\times10^{10}\,\mathrm{GeV}$ on the inflationary Hubble scale. For an initial misalignment angle $\theta_i=1$, the bound strengthens to $H_I<2.2\times10^7\,\mathrm{GeV}$, with still stronger constraints near the hilltop. Combining the isocurvature and tensor spectra yields
axion-tensor and
axion-conditioned Lyth bounds. If the observed
curvature perturbation is generated by a canonical cold single-field slow-roll inflaton and the tensor amplitude varies slowly across the observable CMB window, these relations limit the inflaton excursion to $\Delta\phi_{\rm CMB}/M_{\rm Pl}\lesssim10^{-7}\text{-}10^{-4}$ and require $|M_{\rm Pl}V'/V|\sim10^{-8}\text{-}10^{-5}$ while $M_{\rm Pl}^2V''/V\sim-10^{-2}$. This hierarchy favors models with independent control of the inflationary scale, potential derivatives, exit, and reheating, including hybrid, running-mass, and inflection-point models. Reheating and the requirement of Peccei-Quinn non-restoration sharpen these conditions, while nonminimal scenarios can relax them by modifying the
primordial fluctuation, its transfer, or the relic abundance.
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General Relativity and Quantum Cosmology
Entropic Chaplygin-Gas cosmology and late-universe tension diagnostics
Kelvis A. Kulhkampa, Carlos H. Coimbra-Araújob, Abraão J. S.Capistrano et al. (+2 more)
We investigate an entropic generalized Chaplygin-gas (gCg) cosmology in which a single dark fluid accounts for both dark matter and dark energy. We constrain the model using DESI
baryon acoustic oscillations,
redshift-space-distortion measurements, compressed Planck 2018 distance and
lensing information, and Type Ia
supernova likelihoods with PantheonPlus+SH0ES (PPS) and DES–Dovekie. For Planck+DESI+RSD+PPS, the entropic gCg model yields a Hubble constant of $H_{0}=68.64\pm0.52\,{\rm km\,s^{-1}\,Mpc^{-1}}$ and the amplitude of matter fluctuations parameter of $S_{8}=0.797\pm0.021$, compared with $H_{0}=67.31\pm0.28\,{\rm km\,s^{-1}\,Mpc^{-1}}$ and $S_{8}=0.809\pm0.021$ in $\Lambda$CDM. The simultaneous upward shift in $H_{0}$ and downward shift in $S_{8}$ occurs in the directions required for a partial alleviation of both tensions. We also show that when PPS is replaced by DES–Dovekie, the parameter shifts are smaller, the best-fit improvement is negligible, and the
Bayesian evidence favours $\Lambda$CDM. Thus, the entropic gCg model provides a potentially interesting simultaneous shift of the Hubble constant and the matter-clustering amplitude, but its statistical support depends on the adopted
supernova likelihood.
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All authors Kelvis A. Kulhkampa, Carlos H. Coimbra-Araújob, Abraão J. S.Capistrano, Luiz A. Cabral, José A. P. F. Marão
Physics and Society
Gravitational GateWave: Gravitational waves as LFO modulation amplitude
Carlos Darío Badilla Cerdas
We present an audio gate plugin that uses real gravitational wave strain data from the LIGO and Virgo detectors as low frequency oscillator (LFO) modulation sources. Conventional audio gates rely on synthetic waveforms, sine, triangle, sawtooth, whose fixed harmonic content produces predictable pumping effects. By contrast, gravitational wave chirps from compact binary coalescences sweep through frequency and amplitude on subsecond timescales; when time scaled to LFO rates (0.1 to 10)Hz, these chirps yield modulation signals with continuously evolving harmonic structure. The plugin demonstrates that astrophysical signals can serve as musically compelling modulation sources, bridging sonification and creative audio processing.
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High Energy Physics (Theory)
Comments on deformed phase-space cosmology, SUSY and black holes
O. López-Aguayo, J. C. López-Domínguez, G. E. Pérez-Cuéllar et al. (+1 more)
This paper presents the construction of the supersymmetric (SUSY) deformed version of the time dependent metric that describes the interior of the Schwarzschild BH. First, the noncommutative bosonic model is constructed by inducing the deformation in the minisuperspace coordinates and the associated canonical momentum. Following the methods of SUSY
quantum mechanics, the supercharges of the deformed models are constructed and the deformed SUSY Wheeler-DeWitt equation is obtained. The classical dynamics are also obtained using the WKB approximation, we find the classical solutions and the conditions to satisfy the
Hamiltonian constraint for both the SUSY and bosonic cases. Finally, the effects of the deformation in the context of deformed phase space cosmology and black holes are discussed.
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All authors O. López-Aguayo, J. C. López-Domínguez, G. E. Pérez-Cuéllar, M. Sabido
Cosmology and Nongalactic Astrophysics
Probing Dark Matter Substructure with Wave-Optics Distortions of Strongly Lensed LISA Gravitational Waves
Tonghua Liu, Kai Liao, Marek Biesiada et al. (+1 more)
Strong
lensing changes the phase of a gravitational-wave signal as well as its amplitude and arrival time. We study whether this phase information can distinguish between three dark-matter structures in the lens: a Navarro–Frenk–White
halo (NFW), a self-interacting dark matter (SIDM)
halo, and a fuzzy-dark-matter field (FDM). We generate waveforms for the detectable lensed massive-black-hole-binary population of a four-year LISA mission and fit every signal with the same smooth singular-isothermal-ellipsoid lens with external shear. In 132 lens systems, 311 images are resolved as separate signals in time. NFW and SIDM produce real waveform changes, but their slowly varying part is largely degenerate with the constant, gradient, and Hessian of the smooth Fermat potential at the image. The coherent density fluctuations of FDM leave a larger frequency-dependent residual after this fit. The NFW–FDM and SIDM–FDM populations become distinguishable with about 60 and 110 resolved image waveforms, respectively. These results show that repeated lensed LISA signals can probe the spatial form of dark matter in lens
galaxies, rather than only the total
lensing mass.
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All authors Tonghua Liu, Kai Liao, Marek Biesiada, Jieci Wang
High Energy Physics (Theory)
Exact Nambu-Goto 4-Surfaces and Octonionic Cayley Selection in 8D
Graeme Donald Robertson
We study four-dimensional Euclidean Nambu-Goto
embeddings in eight dimensions in the presence of the
Spin(7)-invariant four-form constructed from octonionic structure constants. A broad class of holomorphic maps is shown by direct substitution to satisfy the nonlinear Nambu-Goto Euler-Lagrange equations. For a compatible
Spin(7) structure these same
embeddings satisfy the Cayley calibration condition. The calculation therefore gives a discrete octonionic selection rule for the relative orientation of an exact Nambu-Goto 4-surface and the
Spin(7) structure of the target.
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Medical Physics · Cross-listed from eess.IV
Metric Surface Reconstruction of Neurosurgical Scenes from Monocular Operating Microscope Images and Microscope Pose
Thomas Bucher, Didier Neuenschwander, Thomas Petutschnigg et al. (+4 more)
Objective: We evaluated whether metric 3D geometry of neurosurgical operative exposure can be recovered from standard
monocular operating-microscope images combined with microscope pose data. Methods: In a phantom-based laboratory study, two aneurysm training phantoms were imaged with a ZEISS Pentero 800 microscope integrated with Brainlab Cranial
Navigation. Microscope images from the standard composite
video output were stored with synchronous microscope poses. After intrinsic and extrinsic calibration, depth was estimated with the pretrained Depth Anything 3 model without task-specific fine-tuning. Fused point clouds were converted to meshes using Poisson surface reconstruction. Reconstructions were compared with reference surfaces from structured-light scanning and fine-slice CT. Results: For phantom A, representing a deeper
surgical corridor, reconstruction accuracy ranged from 1.95 $\pm$ 1.70 mm to 2.33 $\pm$ 2.15 mm. For phantom B, representing a directly exposed surface, accuracy ranged from 1.02 $\pm$ 0.93 mm to 1.52 $\pm$ 1.21 mm. Larger image sets mainly improved completeness, while accuracy remained within a narrower range. Corridor analysis showed preservation of overall geometry with local deviations in incompletely reconstructed regions. Conclusions: Standard
monocular microscope images combined with
navigation-derived pose data can reconstruct millimeter-range 3D surfaces using a foundation-model-based pipeline. These results show technical feasibility in a controlled phantom setting and support further development toward objective quantification of operative exposure, image fusion, and characterization of working spaces for future
surgical instrumentation.
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All authors Thomas Bucher, Didier Neuenschwander, Thomas Petutschnigg, Michael Murek, David Bervini, Andreas Raabe, Manuela Eugster
Astrophysics of Galaxies
LBT-MODS spectroscopy of young stellar objects in the distant metal-poor star forming region Sh2-284: Stellar and accretion properties
Katia Biazzo, Juan Manuel Alcalá, Felice Cusano et al. (+9 more)
We present a spectroscopic survey of young
stellar objects (YSOs) in Sh2-284, a distant (~4.5 kpc), low-
metallicity (Z~1/3 Zsun)
star-forming region (SFR) toward the
Galactic anticenter. Candidate YSOs were selected using mid-infrared Spitzer/IRAC data with optical and near-infrared photometry. Follow-up spectroscopy was conducted with MODS at the Large Binocular
Telescope. We characterize the
stellar and
accretion properties of the disk-bearing population in a metal-poor environment, probing
stellar masses from ~2.95 Msun to ~0.35 Msun. This work constitutes the first wide-field (~45'x45') spectroscopic investigation of YSOs in Sh2-284, providing a comprehensive view of
star formation in this
Galactic environment. We provide tentative first estimates of iron abundance for three low-mass targets and lithium abundance for a limited number of objects, offering an initial characterization of the chemical properties of these
stars. We adopt a multi-diagnostic approach based on nine tracers, exploiting the spectral coverage of the instrument, using H_alpha, H_beta, H_gamma, CaII infrared triplet, Pa_eta, Pa_
zeta, and Pa_epsilon emission lines. We derive key
accretion properties and compare them with those measured in nearby,
solar-
metallicity SFRs to explore potential
metallicity-driven differences in
accretion behavior and disk
evolution. We tentatively find indications of a flattening in the flux-flux relations of the metal-poor YSOs compared to
solar-
metallicity samples, a behavior that is recovered across diagnostics. Our observations indicate that the selected disk-bearing YSOs in this metal-poor environment exhibit resilient
accretion activity, spanning from ~2.3x10^(-10) Msun/yr and ~1.0x10^(-6) Msun/yr, and a median rate of ~2.2x10^(-8) Msun/yr. Overall, this demonstrates that gas
accretion can be efficiently sustained in sub-
solar metallicity environments.
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All authors Katia Biazzo, Juan Manuel Alcalá, Felice Cusano, Mario Guarcello, Diego Paris, Ester Marini, Roberta Carini, Teresa Giannini, Brunella Nisini, Simone Antoniucci, Guido De Marchi, Maria Gabriela Navarro Ovando
Mesoscale and Nanoscale Physics
Supermoiré-trapped quadrupolar exciton
Anish Kumar, Suman Chatterjee, Kenji Watanabe et al. (+2 more)
Moiré-trapped dipolar interlayer
exciton in heterobilayers offers a rich platform to explore interaction-driven phenomena. Extending the number of layers to three and beyond leads to highly intriguing multipolar
exciton - a superposition state of vertically aligned phase-coherent
excitons. However, in experiments, unintentional twist-angle mismatch among layers may degrade the strength and homogeneity of the vertical Coulomb coupling. Here we propose that the supermoiré effect in a heterotrilayer comes to the rescue by creating periodic pockets of vertically aligned atomic registries that facilitate the formation of quadrupolar
excitons trapped in such pockets. Using WS$_2$/WSe$_2$/WS$_2$ stack, we show interaction between multiple confined levels of the top and bottom moiré interfaces, creating electric field tunable multi-level hybridized bright (symmetric) and dark (anti-symmetric) quadrupolar states. Our work underscores the critical role of supermoiré effect in quadrupolar
excitons. The discovery of reduced sensitivity on precise angle-
alignment will ignite exploration of complex excitonic states in multi-layered
heterostructures.
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All authors Anish Kumar, Suman Chatterjee, Kenji Watanabe, Takashi Taniguchi, Kausik Majumdar
Statistical Mechanics
Extreme First-Passage Time of Many Interacting Particles
Ruicheng Bao
Extreme first-passage events are broadly relevant to biological, chemical, and physical processes in which the first successful arrival determines the outcome. Existing theories are largely confined to noninteracting searchers. Interacting extreme-statistics problems are notoriously difficult because correlations destroy probability factorization. We establish a general framework for interacting extreme search. A no-go
theorem shows that broad classes of short-range interactions cannot beat the $1/\ln N$ extreme timescale of $N$ independent Brownian searchers, and complementary upper bounds prove that this scale is exact for repulsive interactions. We then identify three sharp mechanisms beyond the logarithmic class and derive a unified interaction-driven acceleration limit. In particular, deterministic pairwise interaction can at most reduce the extreme search time to order $1/N$, while
stochastic pairwise forcing attains $1/(N\ln N)$. Our results separate acceleration due to statistical redundancy from that generated by coherent many-body transport or amplified fluctuations, deepening our understanding of interacting many-body systems.
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Statistical Mechanics
Effective field theories of nonlinear fluctuating hydrodynamics in one dimension
Matija Koterle and Enej Ilievski
Describing emergent macroscopic phenomena in low spatial dimensions is known to be notoriously challenging, primarily due to strong interactions that render perturbative approaches inapplicable. On the other hand, low-dimensional systems host a wealth of unorthodox phenomena. A prominent example is the emergence of superdiffusive transport in one-dimensional interacting systems, traditionally studied in the framework of nonlinear fluctuating hydrodynamics. After identifying and discussing internal inconsistencies in the previous formulations, in this work we develop a general and systematic approach for constructing effective field theories of one-dimensional hydrodynamic systems in the form of coupled
stochastic Langevin-type equations compatible with the physical requirements of local
equilibrium states - the thermodynamic Maxwell relation and fluctuation-dissipation
symmetry. To exemplify our construction, we devise a numerical integration scheme and implement it on a simple model of two interacting hydrodynamic modes with a non-Gaussian stationary
equilibrium measure.
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Optics
Optomechanical systems with a Fano membrane in the middle
Lei Du, Aymeric Frerejean, Witlef Wieczorek et al. (+2 more)
Conventional membrane-in-the-middle (MIM) optomechanical systems offer limited control over the optical linewidth, which can limit their performance when operating in the unresolved-sideband regime. We investigate cavity optomechanics with a photonic-
crystal Fano membrane placed at the center of a Fabry-Pérot (FP) cavity. In contrast to a conventional dielectric membrane, the photonic-
crystal membrane supports a localized optical resonance, which hybridizes with the cavity field and enables spectral engineering of the relevant optical modes. Besides the usual dispersive optomechanical coupling associated with cavity-length changes, the membrane motion also modifies the Fano-mode resonance and its hybridization with the cavity field. We consider two limits set by the membrane reflectivity: a transparent-membrane regime with a single FP-like mode, and a reflective-membrane regime with two coupled subcavity modes. In the latter case, only the symmetric cavity mode hybridizes with the Fano mode, while the antisymmetric mode remains decoupled. Using
quantum Langevin equations together with a transfer-
matrix description of the optical scattering problem, we show that the Fano-induced hybridization can generate narrow optical normal modes that remain efficiently accessible to the external drive for experimentally realistic parameters. These modes can provide effective sideband resolution and enable ground-state cooling of the membrane motion even when the bare cavity is in the unresolved-sideband regime. Our results establish Fano MIM systems as a promising platform for spectral and optomechanical engineering.
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All authors Lei Du, Aymeric Frerejean, Witlef Wieczorek, Janine Splettstoesser, Juliette Monsel