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2602.02485 2026-02-03 astro-ph.GA

DeepDive: Tracing the early quenching pathways of massive quiescent galaxies at $z>3$ from their star-formation histories and chemical abundances

Massissilia L. Hamadouche, Katherine E. Whitaker, Francesco Valentino, Jacqueline Antwi-Danso, Kei Ito, Aliza Beverage, Pengpei Zhu, Gabriel Brammer, Vasily Kokorev, Gabriella de Lucia, William M. Baker, Marion Farcy, Anna Gallazzi, Steven Gillman, Rashmi Gottumukkala, Michaela Hirschmann, Christian Kragh Jespersen, Takumi Kakimoto, Minju M. Lee, Masato Onodera, Rhythm Shimakawa, Masayuki Tanaka, John R. Weaver, Po-Feng Wu

Comments 22 pages, 10 figures (11 inc. appendix figure), submitted to ApJ. Comments welcome

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We investigate the chemical abundances and star-formation histories (SFH) of ten massive ($\mathrm{log}_{10} (M_{\star}/\mathrm{M}_{\odot})>10.5$) quiescent galaxies at $3<z<4$ using deep, medium-resolution spectroscopic data obtained as part of the \textit{JWST DeepDive} Cycle 2 GO program. Our \textit{DeepDive} sample demonstrates early formation and quenching times inferred from spectro-photometric fitting, with most galaxies having formed 50\% of their stellar mass by $z \sim 5$, and quenching by $z \sim 4$, showing good agreement across the various SFH parameterizations explored in this work. Though they differ slightly between SFH parameterizations, the inferred formation timescales for the {\it DeepDive} sample span both rapid ($\lesssim$ 100 Myr) and more extended ($\gtrsim$ 200 Myr) episodes, corresponding to star formation occurring over a few to several dynamical times given their compact sizes and high densities at $z\sim3-4$. On average, massive quiescent galaxies at $3<z<4$ are $α$-enhanced ($\langle [α/\mathrm{Fe}]\rangle$= $0.22^{+0.22}_{-0.17}$), although there is strong diversity ($\sim0.3$ dex in scatter) among individual [$α$/Fe] values. Our results for $α$-enhancement are consistent with lower-redshift studies, implying weak evolution in [$α$/Fe] from $z \sim 4$ to $z\sim 1$. The SFH timescales associated with the low [$α$/Fe] measurements suggest longer formation timescales, potentially pointing to earlier enrichment by Type Ia supernovae, or metals preferentially being removed via outflows driven either by powerful early active galactic nuclei or supernovae. Overall, this work represents the first, statistically representative combined study of the star-formation histories and chemical abundances of massive quiescent galaxies at $z>3$.

2602.02478 2026-02-03 cond-mat.str-el cond-mat.mes-hall

Orbital Magnetization of Interacting Electrons

Xi Chen, Zhi-Da Song

Comments 11 pages, 2 figures

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We derive an exact expression for the orbital magnetization of electrons with short-range interactions (such as density-density interactions) in terms of exact zero-frequency response functions of the zero-field system. The result applies to weakly and strongly correlated electrons at zero and finite temperature, provided that the local grand potential density only depends on local thermodynamic parameters. We benchmark the formula for non-interacting and weakly-coupled electrons. To zeroth and first orders in the interaction strength, it agrees with the modern theory of orbital magnetization and its recent generalization to self-consistent Hartree-Fock bands. Our work provides an exact framework of interacting orbital magnetization beyond mean-field treatments, and paves the way for quantitative studies of strongly correlated electrons in external magnetic fields.

2602.02442 2026-02-03 astro-ph.IM physics.ins-det

Depth Calibration of Double-sided Strip Germanium Detectors for the Compton Spectrometer and Imager Satellite

Field R. Rogers, Sean N. Pike, Samer Alnussirat, Robin Anthony-Petersen, Steven E. Boggs, Felix Hagemann, Sophia E. Haight, Alyson Joens, Carolyn Kierans, Alexander Lowell, Brent Mochizuki, Albert Y. Shih, Clio Sleator, John A. Tomsick, Andreas Zoglauer

Comments Manuscript accepted at NIM A. 9 pages, 8 figures

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Double-sided strip high-purity germanium detectors with three-dimensional position reconstruction capability have been developed over three decades, with space-based applications in high-energy astrophysics and heliophysics. Position resolution in three dimensions is key to reconstruction of Compton scattering events, including for the upcoming Compton Spectrometer and Imager (COSI) satellite mission. Two-dimensional position reconstruction is enabled by segmentation of the two detector faces into orthogonal strip contacts, enabling a pixelized analysis. The depth of an interaction cannot be measured directly but must be inferred from the charge collection time difference between the two faces of the detector. Here, we demonstrate for the first time the depth calibration of a detector with the COSI satellite geometry read out using an application specific integrated circuit (ASIC) developed for the COSI mission. In this work, we map collection time difference to depth using the Julia-based simulation package SolidStateDetectors$.$jl and validate it with comparison to the timing distributions observed in data. We also use simulations and data to demonstrate the depth resolution on a per-pixel basis, with >90% of pixels having <0.9 mm (FWHM) resolution at 59.5 keV and <0.6 mm (FWHM) resolution at 122.1 keV.

2512.05768 2026-02-03 astro-ph.SR astro-ph.EP astro-ph.GA

Multi-band ALMA Polarization Observations of BHB07-11 Reveal Aligned Dust Grains in Complex Spiral Arm Structures

Austen Fourkas, Leslie W. Looney, Zhe-Yu Daniel Lin, Martin Radecki, Zhi-Yun Li, John J. Tobin, Ian W. Stephens, Manuel Fernández-López, Haifeng Yang, Woojin Kwon, Rachel Harrison

Comments Accepted to ApJ, 30 pages, 21 figures

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Polarization-mode observations from the Atacama Large Millimeter/submillimeter Array (ALMA) are powerful tools for studying the dust grain populations in circumstellar disks. Many sources exhibit polarization signatures consistent with aligned dust grains, yet the physical origin of this alignment remains uncertain. One such source is BHB07-11, a Class I protobinary object in the Pipe Nebula with complex spiral arm structures in its circumbinary disk. While magnetic fields are often invoked to explain grain alignment in the interstellar medium, the contrasting conditions in circumstellar disk environments demand further investigation into grain alignment mechanisms. To determine BHB07-11's dominant polarization mechanism, we leverage ALMA polarization-mode dust continuum observations in Bands 3 ($λ$=3.1 mm), 6 ($λ$=1.3 mm), and 7 ($λ$=0.87 mm), in combination with high-resolution dust continuum and spectral line observations in Band 6. Observed polarization vectors in each band are consistent with emission from aligned grains and follow the structure of the spiral arms as shown in the high-resolution observations. Given the relationship between the observed polarization vector orientation and the spiral arms, we find that the polarization morphology is most consistent with grains aligned through a relative velocity flow between gas and dust in the spiral arms, as envisioned in the recently developed badminton birdie-like alignment mechanism, rather than alignment with a magnetic field or other known alignment mechanisms.

2602.02463 2026-02-03 physics.optics cond-mat.mtrl-sci

Numerically optimized FROG results for the study of red-shifted spectra in multi-frequency Raman generation

Sakthi Priya Amirtharaj, Zujun Xu, Donna Strickland, Borun Chowdhury, Sagnik Acharya, Priyam Samantray, Anil Prabhakar, Kisor Kumar Sahu, Franz Bamer, S. Swayamjyoti

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When multifrequency Raman scattering is driven in the transient regime by two chirped pump pulses, the resulting anti-Stokes orders exhibit asymmetric spectral broadening toward lower frequencies, leading to a characteristic double-peaked structure in each order. In this Letter, frequency-resolved optical gating (FROG) is used to investigate the spectral evolution of the first anti-Stokes Raman component. To interpret the observed features, we introduce a double-pulse interference model and employ an adaptive learning-based reconstruction algorithm using the Adam optimizer to retrieve the temporal field evolution. The simulation results show good agreement with the experimental measurements. Our analysis indicates that the observed red-shifted spectral component originates from linear Raman processes within the two-photon dressed-state framework.

2602.02461 2026-02-03 astro-ph.IM physics.space-ph

X-ray characterization of fully-depleted p-channel Skipper-CCDs for the DarkNESS mission

Phoenix Alpine, Ana M. Botti, Brenda A. Cervantes-Vergara, Claudio R. Chavez, Fernando Chierchie, Alex Drlica-Wagner, Juan Estrada, Erez Etzion, Michael Lembeck, Pilar López Maggi, Joseph Noonan, Brandon Roach, Nathan Saffold, Javier Tiffenberg

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The Dark matter Nanosatellite Equipped with Skipper Sensors (DarkNESS) mission is a 6U CubeSat designed to search for X-ray lines from decaying dark matter using Skipper-CCDs. Thick, fully-depleted p-channel Skipper-CCDs provide low readout noise and high quantum efficiency for 1-10 keV X-rays, but their X-ray performance has not yet been demonstrated in the space environment. DarkNESS will operate in low-Earth orbit, where trapped protons induce displacement damage in the sensor that increases charge-transfer inefficiency and degrades the X-ray energy resolution. This work measures the X-ray line response of Skipper-CCDs before and after proton irradiation and quantifies the associated degradation. A sensor was exposed to 217 MeV protons at a fluence of 8.4 x 10^10 protons cm^-2, corresponding to a displacement-damage dose more than an order of magnitude above the three-year expectation for representative mid-inclination and Sun-synchronous low-Earth orbits. A 55Fe source was used to compare the energy resolution of the beam-exposed quadrant to adjacent unexposed quadrants and a non-irradiated reference sensor. These measurements provide a quantitative assessment of radiation-induced spectral degradation in Skipper-CCDs and enable an estimate of the end-of-life X-ray energy resolution expected for DarkNESS operation in low-Earth orbit.

2602.02460 2026-02-03 cond-mat.stat-mech

Resolution of the Two-Dimensional Ferromagnetic Spin-3/2 Ising Model via Cluster Growth

J. Roberto Viana, Octavio D. Rodriguez Salmon, Minos A. Neto, Griffith Mendonça, F. Dinóla Neto

Comments Twelve figures, 29 pages

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We propose a computational methodology based on a hierarchical cluster growth process to solve spin-3/2 Ising models efficiently. The method circumvents the exponential complexity (\(4^{N}\)) of the canonical ensemble partition function by iteratively constructing finite magnetic clusters of size \(N_g\), where the effective spin state of a site in generation \(g+1\) is determined by the local magnetization of a cluster from generation \(g\). This approach, which shares conceptual ground with effective field theories, allows the study of systems of effectively very large size \(N = N_0 (N_g)^{g}\). We apply the formalism to the ferromagnetic spin-3/2 Ising model on a honeycomb lattice, modeling the monolayer CrI$_3$, a prototypical two-dimensional Ising magnet. The model, calibrated using the experimental transition temperature (\(T_{c} \simeq 45\) K), successfully reproduces key experimental features: the temperature dependence of the magnetization \(m(T)\), including its inflection point, and the broadened peak in the specific heat \(c_v(T)\). We also compute the entropy \(s(T)\), finding a finite residual value at low temperatures consistent with the system's double degeneracy. Our results demonstrate that this hierarchical cluster method provides a quantitatively accurate and computationally efficient framework for studying complex magnetic systems.

2602.02446 2026-02-03 cond-mat.stat-mech math.PR

Renewal theory for a run-and-tumble particle with stochastic resetting and a sticky boundary

Paul C Bressloff, Samantha Linn

Comments 18 pages, 10 figures

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We consider a run-and-tumble particle (RTP) with stochastic resetting confined to the half line $[0,\infty)$ with a sticky boundary at $x=0$. In the bulk the RTP tumbles at a constant rate $α>0$ between velocity states $\pm v$ with $v>0$ and randomly resets to its initial position and orientation $(x_0,k_0)\in(\mathbb{R}^+,\pm)$. When the RTP reaches the target at $x=0$ it attaches to the boundary for a random waiting time before either detaching and continuing to navigate the bulk domain or (permanently) entering the target. These events are the analogs of adsorption, desorption, and absorption of a particle by a partially reactive surface in physical chemistry. We use renewal theory to characterize the particle trajectory in terms of successive binding events under two distinct desorption protocols: via resetting to $(x_0,k_0)$ and via continuous movement from $x=0$ with velocity $+v$. First we derive the nonequilibrum stationary state (NESS) in the case of no absorption and characterize the accumulation at the boundary. Second, we compute the mean first passage time (MFPT) statistics. In addition to observing the usual unimodal dependence of the MFPT on bulk resetting, both the NESS and MFPT strongly depend on the initial orientation $k_0$ and the desorption protocol. For instance, if the initial orientation is toward the boundary, we find that the desorption-induced resetting protocol can reduce the MFPT more effectively than the non-resetting desorption protocol. We also show how matching the desorption kinetics with the bulk resetting or tumbling rate introduces a trade-off between minimizing the adsorption and absorption times. In this setting we find that the desorption protocol which minimizes the absorption MFPT for a given set of parameters is almost always the opposite of that favored when desorption and bulk kinetics are not the same.

2602.02434 2026-02-03 cond-mat.mes-hall cond-mat.str-el

Dynamic nuclear spin polarization in the fractional quantum Hall effect spin transitions

Haotian Zhou, Yuli Lyanda-Geller

Comments 23 Pages, 9 Figures

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Experiments suggest that nuclear spins play a significant role in the quantum Hall effect (QHE) near integer and fractional QHE spin transitions, but many of these phenomena still remain to be understood. Here we study theoretically the dynamic nuclear polarization (DNP) in the two-dimensional electron liquid near a quantum point contact (QPC) or a domain wall between spin polarized and unpolarized phases induced by electrostatic gating in the fractional QHE at a filling factor 2/3 and analyze the dependence of the spin transition on temperature and the magnitude of the flowing current. We demonstrate that nearly all nuclear spins in the QPC or in the domain wall can be polarized by the electric current. The Overhauser effective magnetic field from the DNP can be strong enough to induce (or modify) a phase transition between polarized and unpolarized phases. This changes the gate voltages and magnetic fields required for the spin transitions, and leads to the reconstruction of the boundary between two phases and a domain wall and a current path displacement. The spread of nuclear spin polarization and the domain wall displacement are strongly asymmetric with respect to the direction of the current flow. Equilibration due to hyperfine interactions and its role on the nuclear spin polarization, domain wall displacements and spin transitions is studied. Back and forth oscillatory transitions between polarized and unpolarized phases near a source contact are discussed. Hyperfine interactions of nuclear spins provide a route for observation and control of the parafermion zero modes that can be induced when the domain wall between the polarized and unpolarized regions is placed in the proximity of a superconductor

2602.02433 2026-02-03 cond-mat.str-el quant-ph

Nonlinear light cone spreading of correlations in a triangular quantum magnet: a hard quantum simulation target

A. Scheie, J. Willsher, E. A. Ghioldi, Kevin Wang, P. Laurell, J. E. Moore, C. D. Batista, J. Knolle, D. Alan Tennant

Comments 5 pages, 3 figures. 11 pages supplemental information

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Dynamical correlations of quantum many-body systems are typically analyzed in the momentum space and frequency basis. However, quantum simulators operate more naturally in real space, real time settings. Here we analyze the real-space time-dependent van Hove spin correlations $G(r,t)$ of the 2D triangular antiferromagnet KYbSe$_2$ as obtained from high-resolution Fourier-transformed neutron spectroscopy. We compare this to $G(r,t)$ from five theoretical simulations of the well-established spin Hamiltonian. Our analysis reveals non-linear sub-ballistic low-temperature transport in KYbSe$_2$ which none of the current state-of-the-art numerical or field-theoretical methods reproduce. Our observation signals an emergent collective hydrodynamics, perhaps associated with the quantum critical phase of a quantum spin liquid, and provides an ideal benchmark for future quantum simulations.

2602.02421 2026-02-03 astro-ph.SR physics.flu-dyn

Nonlinear interaction between dynamo-generated magnetic fields, mean flows and internal gravity waves in stellar stably-stratified layers: From 3D to 1D

Florentin Daniel, Ludovic Petitdemange, Charly Pinçon, Kévin Belkacem, Bruno Longo, Christophe Gissinger

Comments 32 pages, 10 figures, accepted for publication in Geophysical and Astrophysical Fluid Dynamics

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Magnetic fields have been constrained at the surface of several massive and intermediate-mass stars, but their origin and properties in deep stellar radiative interiors are still debated, despite recent detections in the core of some red giant stars. Therefore, the modelling of AM transport in stellar radiative layers only relies on theoretical and numerical estimates of magnetic fields. Recent 3D numerical simulations show that a dynamo could occur in deep radiative regions. A realistic setup for understanding AM transport in such layers thus requires to take into account the mutual interactions of IGW and dynamo-generated magnetic field. We model the dynamics induced by IGW and dynamo in rotating radiative stellar layers using a simple description applicable to various evolutionary stages. As dynamo action and the propagation of IGW are 3D processes that have characteristic timescales short compared to periods associated with structural evolution of stars, we propose a mean-field 1D model by taking advantage of the dynamo coefficients computed from 3D spherical simulations. In this model, the necessary mean shear flow to trigger the dynamo results from the dissipation of monochromatic IGW generated in existing adjacent convective layers, which are expected to drive the formation of an oscillating rotational shear layer, the so-called Shear Layer Oscillation (SLO). In turn, magnetic effects can act on the mean flow through the Lorentz force. We show that the inclusion of magnetic fields adds up to the already very complex nonlinear problem and gives rise to the emergence of new dynamical regimes. Particularly, the fast SLO generated very close to the place where IGW are generated is perturbed by magnetic fields. This dynamical change can filter the wave energy spectrum transmitted towards further layers, with potential influence on the long-term evolution of the inner rotation.

2602.02410 2026-02-03 astro-ph.CO astro-ph.IM

Mitigating half-wave plate systematics at the map-making level: calibration requirements for LiteBIRD

N. Raffuzzi, A. Carones, M. Monelli, S. Giardiello, L. Pagano, Y. Sakurai, H. Ishino, E. Allys, A. Anand, J. Aumont, A. J. Banday, G. Barbieri Ripamonti, R. B. Barreiro, N. Bartolo, S. Basak, A. Basyrov, A. Besnard, M. Bortolami, T. Brinckmann, F. Cacciotti, E. Calabrese, P. Campeti, F. Carralot, F. J. Casas, J. Chandran, K. Cheung, M. Citran, L. Clermont, F. Columbro, A. Coppolecchia, F. Cuttaia, P. de Bernardis, T. de Haan, M. De Lucia, P. Diego-Palazuelos, H. K. Eriksen, F. Finelli, C. Franceschet, U. Fuskeland, G. Galloni, M. Galloway, M. Gerbino, M. Gervasi, T. Ghigna, C. Gimeno-Amo, A. Gruppuso, M. Hazumi, S. Henrot-Versillé, L. T. Hergt, E. Hivon, K. Kohri, L. Lamagna, M. Lattanzi, C. Leloup, F. Levrier, A. I. Lonappan, M. López-Caniego, G. Luzzi, J. Macias-Perez, V. Maranchery, E. Martínez-González, S. Masi, S. Matarrese, T. Matsumura, S. Micheli, M. Migliaccio, G. Morgante, L. Mousset, R. Nagata, T. Namikawa, P. Natoli, A. Novelli, F. Noviello, A. Occhiuzzi, A. Paiella, D. Paoletti, G. Pascual-Cisneros, G. Patanchon, F. Piacentini, G. Piccirilli, M. Pinchera, G. Polenta, L. Porcelli, M. Remazeilles, A. Ritacco, M. Ruiz-Granda, L. Salvati, J. Sanghavi, V. Sauvage, D. Scott, M. Shiraishi, G. Signorelli, R. M. Sullivan, Y. Takase, L. Terenzi, M. Tomasi, M. Tristram, L. Vacher, B. van Tent, P. Vielva, S. Vinzl, I. K. Wehus, G. Weymann-Despres, E. J. Wollack

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Although half-wave plates (HWPs) are becoming a popular choice of polarization modulators for cosmic microwave background (CMB) experiments, their non-idealities can introduce systematic effects that should be carefully characterized and mitigated. One possible mitigation strategy is to incorporate information about the non-idealities at the map-making level, which helps to reduce the HWP-induced distortions of the reconstructed CMB. Nevertheless, the non-idealities can only be known with finite precision. In this paper we investigate the consequences of discrepancies between their true frequency profiles and those assumed by the map-maker. We present an end-to-end framework, including a blind component-separation step, and use it to translate these discrepancies into a bias on the tensor-to-scalar ratio, $r$, for the LiteBIRD satellite mission. We subsequently derive realistic and conservative measurement requirements for accurately characterizing the HWP non-idealities to ensure they do not compromise LiteBIRD's ambitious scientific goals. We find that the obtained results are robust against sky models with varying complexity.

2602.02407 2026-02-03 physics.optics

Impact of interference between two infrared pulses driving high harmonic generation

Sarang Dev Ganeshamandiram, Jahanzeb Muhammad, Marvin Schmoll, Ronak Shah, Frank Stienkemeier, Giuseppe Sansone, Lukas Bruder

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Extreme ultraviolet (XUV) interferometry is technically challenging to implement. One approach to generating interference between two XUV pulses relies on driving high-harmonic generation in a gas jet with two collinearly overlapping infrared laser pulses. We investigate this scheme through a combined experimental and theoretical study, with particular emphasis on the regime of temporal overlap between the driving pulses. A special phase-modulation interferometry technique is implemented to increase the sensitivity for the comprehensive mapping of the strong-field induced high-order nonlinear response. We find that the dynamics arising from the interference of the two electric fields can be adequately described by the non-perturbative model developed by Lewenstein and co-workers.

2602.02402 2026-02-03 cs.RO cs.AI cs.CV physics.app-ph

SoMA: A Real-to-Sim Neural Simulator for Robotic Soft-body Manipulation

Mu Huang, Hui Wang, Kerui Ren, Linning Xu, Yunsong Zhou, Mulin Yu, Bo Dai, Jiangmiao Pang

Comments Project page: https://city-super.github.io/SoMA/

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Simulating deformable objects under rich interactions remains a fundamental challenge for real-to-sim robot manipulation, with dynamics jointly driven by environmental effects and robot actions. Existing simulators rely on predefined physics or data-driven dynamics without robot-conditioned control, limiting accuracy, stability, and generalization. This paper presents SoMA, a 3D Gaussian Splat simulator for soft-body manipulation. SoMA couples deformable dynamics, environmental forces, and robot joint actions in a unified latent neural space for end-to-end real-to-sim simulation. Modeling interactions over learned Gaussian splats enables controllable, stable long-horizon manipulation and generalization beyond observed trajectories without predefined physical models. SoMA improves resimulation accuracy and generalization on real-world robot manipulation by 20%, enabling stable simulation of complex tasks such as long-horizon cloth folding.

2602.02399 2026-02-03 hep-ph

Study of Form Factors and Observables in $B_c^- \rightarrow D_{s}^{*-}\ell^+\ell^-$ and $B_c^- \rightarrow D_{s}^{*-}ν\barν$ decays

Utsab Dey, Soumitra Nandi

Comments 51 pages, 25 tables, 11 figures

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We investigate the decays $B_c^- \rightarrow D_{s}^{(*)-}\ell^+\ell^-$ and $B_c^- \rightarrow D_{s}^{(*)-}ν\barν$ within the Standard Model (SM), employing perturbative QCD form factors that are sensitive to the wave functions of $B_c$ and $D_{s}^{(*)}$ mesons. We determine the shape parameters of these mesons and the $B_c \to D_s^{(*)}$ form factors at $q^2 = 0$ from available lattice QCD inputs for $B_s \to D_s^{(*)}$ and $B_c \to D_s$ transitions. To obtain the $q^2$ dependence of the $B_c \to D_s^*$ form factors, we employ heavy-quark spin symmetry and an appropriate parametrisation scheme over the allowed $q^2$ region. Based on these inputs, we present predictions for branching ratios and lepton-flavour-sensitive observables. Furthermore, we perform a detailed angular analysis of the cascade decay $B_c^- \to D_s^{*-}(\to D_s^- π^0)\,\ell^+\ell^-$, providing Standard Model predictions for several angular observables.

2602.02392 2026-02-03 astro-ph.EP

What to make of the Earth's curiously intermediate land fraction?

David Kipping

Comments Accepted to AJ

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Approximately two-thirds of the Earth, the only known inhabited planet, is covered in ocean. Why not 0.01% or 99.99%? It has been previously suggested that this may represent a certain degree of fine-tuning, and thus perhaps observers are a-priori more likely to develop on those rare worlds with nearly equal land-ocean ratios, such as our own. In this work, we take the single datum of the Earth and then use Bayesian inference to compare four models for the probability distribution of a planet becoming inhabited by observers as a function of land-fraction, $f$, which we classify as i) land-centric ii) ocean-centric iii) equi-centric and iv) indifference. We find that no model is strongly favoured over the others, but that 1) the land-centric model is disfavoured over all others, and, 2) the equi-centric model is favoured over all competitors. Further, we show that more extreme models with heavy tail-weighting are strongly disfavoured even when conditioned upon the Earth alone. For example, a land-centric model where the median planet has $f=0.82$ (or greater) is in strong tension with our existence. Finally, we consider the potential addition of more data via Mars or exoplanets. Should paleo-Mars have once harboured life and had $f<0.20$, then this would strongly favour the ocean-centric model for life, over a land-centric hypothesis. We show that strong evidence for/against the equi-centric model versus its competitors would likely require at least a dozen inhabited exoplanets, offering a well-motivated sample size for future experiments.

2602.02390 2026-02-03 astro-ph.HE astro-ph.CO astro-ph.GA hep-ph

Evaluating the Contribution of Active Galactic Nuclei to the Diffuse High-Energy Neutrino Flux

Samyak Jain, Dan Hooper, Francis Halzen

Comments 24 pages, 8 figures

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The detection of high-energy neutrinos from NGC 1068 and TXS-0506+56 suggests that active galactic nuclei (AGN) may contribute significantly to the the diffuse neutrino flux measured by IceCube. Using 10 years of publicly available IceCube data, we performed a systematic population analysis of X-ray-bright and gamma-ray-bright AGN to evaluate the extent to which this diffuse flux could originate from these sources. We find that gamma-ray-bright blazars can account for no more than 16\% of IceCube's total diffuse flux. Although we find no evidence of neutrino emission from gamma-ray-bright, non-blazar AGN, we cannot exclude the possibility that these sources contribute significantly to the diffuse flux. In contrast, we report (pre-trials) evidence of neutrino emission from several nearby, X-ray-bright, Seyfert-type AGN, including \mbox{NGC 1068} ($4.9σ$), SWIFT J1041.4-1740 ($2.6σ$), SWIFT J0202.4+6824A/B ($2.6σ$), SWIFT J0744.0+2914 (2.6$σ$), NGC 4151 ($2.5σ$), and NGC 3079 ($2.5σ$). Although not fully conclusive, these results suggest that IceCube may be detecting neutrinos from a larger population of Seyfert galaxies. The fact that these sources are not gamma-ray bright indicates that their neutrino production must be taking place in optically thick environments, such as in the coronae surrounding these galaxies' supermassive black holes. We also identify a $4.2σ$ correlation between the neutrinos detected by IceCube and members of the Swift-BAT catalog of X-ray-bright AGN, although this correlation is dominated by NGC 1068. We estimate that this class of sources contributes between 11.2\% and the entirety of IceCube's total diffuse neutrino flux. These results strengthen the emerging case for the prevalence of gamma-ray-obscured AGN as significant sources of high-energy neutrinos.

2602.02367 2026-02-03 astro-ph.HE astro-ph.IM

Multi-Messenger Modeling of Low-Luminosity Gamma-Ray Bursts

Shiqi Yu, Bing Theodore Zhang

Comments 14 pages plus 3 pages of appendix. 11 figures and 5 tables in total. accepted by APJ

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Low-luminosity gamma-ray bursts (LL GRBs), a subclass of the most powerful transients in the Universe, remain promising sources of high-energy astrophysical neutrinos, despite strong IceCube constraints on typical long GRBs. In this work, a novel approach is introduced to study a sample of seven LL~GRBs with their multi-wavelength observations to investigate leptohadronic processes during their prompt emission phases. The relative energy densities in magnetic fields, non-thermal electrons, and protons are constrained, with the latter defining the cosmic-ray (CR) loading factor. Our results suggest that LL~GRBs exhibit diverse emission processes, as confirmed by a machine-learning analysis of the fitted parameters. Across the seven LL~GRBs, we find the posterior medians of the CR loading factor in the range of $ξ_p \sim 0.2$--$1.6$. GRB~060218 and GRB~100316D, the lowest-luminosity bursts ($L_{γ, \rm iso} \sim 10^{46}$-$10^{47}\rm~erg~s^{-1}$) consistent with the shock-breakout (SBO) scenario, yield the highest CR loading factor and therefore are expected to produce neutrinos more efficiently. Our model predicts the expected number of neutrino signals that are consistent with current limits but would be detectable with next-generation neutrino observatories. These results strengthen the case for LL~GRBs as promising sources of high-energy astrophysical neutrinos and motivate real-time searches for coincident LL~GRB and neutrino events. Next-generation X-ray and MeV facilities will be critical for identifying more LL~GRBs and strengthening their role in multi-messenger astrophysics.

2602.02364 2026-02-03 quant-ph cs.CR

Guaranteeing Privacy in Hybrid Quantum Learning through Theoretical Mechanisms

Hoang M. Ngo, Tre' R. Jeter, Incheol Shin, Wanli Xing, Tamer Kahveci, My T. Thai

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Quantum Machine Learning (QML) is becoming increasingly prevalent due to its potential to enhance classical machine learning (ML) tasks, such as classification. Although quantum noise is often viewed as a major challenge in quantum computing, it also offers a unique opportunity to enhance privacy. In particular, intrinsic quantum noise provides a natural stochastic resource that, when rigorously analyzed within the differential privacy (DP) framework and composed with classical mechanisms, can satisfy formal $(\varepsilon, δ)$-DP guarantees. This enables a reduction in the required classical perturbation without compromising the privacy budget, potentially improving model utility. However, the integration of classical and quantum noise for privacy preservation remains unexplored. In this work, we propose a hybrid noise-added mechanism, HYPER-Q, that combines classical and quantum noise to protect the privacy of QML models. We provide a comprehensive analysis of its privacy guarantees and establish theoretical bounds on its utility. Empirically, we demonstrate that HYPER-Q outperforms existing classical noise-based mechanisms in terms of adversarial robustness across multiple real-world datasets.

2602.02363 2026-02-03 astro-ph.CO

Reconstructing the largest scales of the Universe with field-level inference applied to the Quaia Quasar Catalogue

Adam Andrews, Arthur Loureiro, Jens Jasche, Stuart McAlpine, Guilhem Lavaux, Florent Leclercq

Comments 25 pages, 22 figures. Comments welcome!

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The recently released Quaia quasar catalogue, with its broad redshift range and all-sky coverage, enables unprecedented three-dimensional reconstructions of matter across cosmic time. In this work, we apply the field-level inference algorithm BORG to the Quaia catalogues to reconstruct the initial conditions and present-day matter distribution of the Universe. We employ a physics-based forward model of large-scale structure using Lagrangian perturbation theory, incorporating light-cone effects, redshift-space distortions, quasar bias, and survey selection effects. This approach enables a detailed and physically motivated inference of the three-dimensional density field and initial conditions over the entire cosmic volume considered. We analyse both the G < 20.0 (Quaia Clean) and G < 20.5 (Quaia Deep) samples, where G denotes the Gaia broad optical-band magnitude, imposing conservative sky cuts to ensure robustness against foreground contamination. The resulting reconstructions span a comoving volume of (10h^{-1} Gpc)^3 with a maximum spatial resolution of 39.1 h^{-1}Mpc, making this the largest field-level reconstruction of the observable Universe in terms of comoving volume to date. We validate our reconstructions through a range of internal and external consistency checks, including the cross-correlation of the inferred density fields with Planck CMB lensing, where we detect a signal at ~4σsignificance. Beyond delivering high-fidelity data products, including posterior maps of initial conditions, present-day dark matter, and velocity fields, this work establishes a framework for exploiting quasar surveys in field-level cosmology.

2602.02362 2026-02-03 hep-ph

Pseudo-Goldstone Neutrinos and Majoron Phenomenology from Spontaneous $U(1){Lμ-L_τ}$ Breaking

Gayatri Ghosh

Comments 28 pages, 9 Figures

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We present a predictive framework for neutrino mass generation based on the spontaneous breaking of a leptonic $U(1)_{L_μ-L_τ}$ symmetry within a supersymmetric setting. The breaking of the global symmetry gives rise to a Majoron-like axion-like particle and a pseudo-Goldstone right-handed neutrino whose mass is naturally suppressed by supersymmetry-breaking effects. The interplay between the pseudo-Goldstone neutrino and the low-scale seesaw mechanism leads to a structured neutrino mass matrix capable of reproducing the observed neutrino masses, mixing angles, and CP-violating phase without invoking extreme parameter hierarchies. We perform a numerical fit to current neutrino oscillation data and identify representative benchmark solutions consistent with laboratory constraints as well as cosmological and astrophysical bounds. A characteristic outcome of the framework is the emergence of correlated relations linking the symmetry breaking scale, heavy neutrino masses, Majoron couplings, and neutrino lifetimes. Majoron-induced invisible neutrino decay arises generically and can significantly modify cosmological neutrino mass constraints for sufficiently low symmetry breaking scales. We discuss the phenomenological implications across neutrino oscillation experiments, cosmology, and collider searches for long-lived heavy neutrinos. While a detailed experimental simulation is beyond the scope of this work, existing sensitivity projections indicate that portions of the parameter space may become accessible in future facilities. The combined interplay of laboratory probes and cosmological observations provides a consistent and testable picture of neutrino mass generation tied to spontaneous leptonic symmetry breaking and axion-like physics.

2602.02357 2026-02-03 hep-th gr-qc

Black Hole Evaporation as a Topological Tunneling

Victor H. Alencar

Comments 15 pages and 4 figures

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We present the quantization of the electromagnetic field near the event horizon of a Schwarzschild black hole using Euclidean path integrals. Our result for the vacuum energy describes a black hole surrounded by a finite volume of photons at $T_{H} = \frac{1}{8πG M}$, the black hole quantum atmosphere. The total entropy includes contributions from this atmosphere, and the Bekenstein entropy, which arises from the Gibbons--Hawking--York boundary term, which encodes topological information. We show that the contribution of the quantum atmosphere to the black hole specific heat is positive, indicating that the system may become thermodynamically stable. By analyzing homology groups, we show that the black hole evaporation is a tunneling between topologically distinct spacetimes: Schwarzschild ($χ= 2)$ transitions to the flat spacetime ($χ= 1$) via Hawking radiation, where $χ$ is the Euler characteristic, a topological invariant. This process resembles instanton-driven tunneling in Yang-Mills theories, where topologically non-trivial solutions dominate the vacuum amplitude. In our case, the Gibbons--Hawking--York term dominates the transition amplitude, which induces the evaporation process. These results corroborate the Parikh-Wilczek picture of Hawking radiation and the interpretation of Euclidean black holes as gravitational instantons.

2602.02351 2026-02-03 hep-ph cs.AI cs.LG

Artificial Intelligence and Symmetries: Learning, Encoding, and Discovering Structure in Physical Data

Veronica Sanz

Comments 25 pages, 9 figures. This manuscript is an invited review at the International Journal of Modern Physics A

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Symmetries play a central role in physics, organizing dynamics, constraining interactions, and determining the effective number of physical degrees of freedom. In parallel, modern artificial intelligence methods have demonstrated a remarkable ability to extract low-dimensional structure from high-dimensional data through representation learning. This review examines the interplay between these two perspectives, focusing on the extent to which symmetry-induced constraints can be identified, encoded, or diagnosed using machine learning techniques. Rather than emphasizing architectures that enforce known symmetries by construction, we concentrate on data-driven approaches and latent representation learning, with particular attention to variational autoencoders. We discuss how symmetries and conservation laws reduce the intrinsic dimensionality of physical datasets, and how this reduction may manifest itself through self-organization of latent spaces in generative models trained to balance reconstruction and compression. We review recent results, including case studies from simple geometric systems and particle physics processes, and analyze the theoretical and practical limitations of inferring symmetry structure without explicit inductive bias.

2602.02339 2026-02-03 astro-ph.CO

Negentropy as Diagnostic of Cosmic Density Fields and Dynamical Dark Energy Models

Suman Sarkar

Comments 25 pages (including appendix), 5 figures, 4 tables. Comments and suggestions are welcome

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We employ negentropy ($J$), defined as the difference between the information content of a non-Gaussian probability distribution and a Gaussian with identical variance, as an information-theoretic probe of non-Gaussianity in the cosmic density field. We quantify its sensitivity to dynamical dark energy by studying the evolution of $J(a)$ and its derivatives $Γ_1(a)$ and $Γ_2(a)$ across three parameterisation schemes: CPL, JBP, and BA. We determine the characteristic redshift $z_{NG}$, marking the epoch of maximal non-Gaussian structure formation, and the turnaround redshift $z_{TA}$, when information production transitions due to dark-energy domination, finding $z_{NG}\sim0.81$ and $z_{TA}\sim0.18$ for $Λ$CDM. Our diagnostics clearly discriminate between thawing and freezing quintessence models and phantom dark energy at low redshifts. Thawing models show small departures from $Λ$CDM, freezing models display higher $z_{TA}$, while phantom models exhibit lower $z_{TA}$, reflecting late-time evolution. We provide a practical prescription for measuring negentropy from discrete galaxy distributions, establishing a framework that can be applied to simulations and observations. This information-theoretic approach offers a robust and complementary tool for probing dark energy dynamics, enabling sensitive discrimination between evolving and cosmological-constant scenarios.

2602.02337 2026-02-03 physics.soc-ph nlin.AO

Patterns in Conflict Dynamics in Yemen and Syria

Moussa Abdou, Neil F. Johnson

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Conflict fatalities tend to follow heavy-tailed statistical distributions. A 2005 fusion-fission theory predicts mathematically that for armed groups operating in dynamically evolving clusters within a given conflict, the number of fatalities per conflict event will follow an approximate power-law distribution with exponent near 2.5, with the specific exponent value offering insight into the relative robustness of larger versus smaller clusters of fighters in that armed group. Since Yemen and Syria are current hotspots for future conflict, yet their most recent conflicts (2023-2025) have not been studied at the event level, we use ACLED data to determine their best-fit exponent value as each conflict evolved. We find that the exponent lies between 2.5 and 3.5 predominantly throughout each conflict, which suggests that the fighters in each of these conflicts continued to operate in smaller clusters as the conflict evolved. Moreover, temporary reductions in the exponent value -- which suggests a temporary increase in the robustness and involvement of larger clusters of fighters -- appear to arise during major crises ahead of the largest battles. Though the lack higher-quality data for these conflicts prevents us from establishing this more firmly, such a temporary reduction in the exponent value hints at its potential use as an early-warning signature.

2602.02336 2026-02-03 nucl-th nucl-ex

Investigation of the shape of uranium in relativistic $^{238}$U+$^{238}$U collisions with nuclear densities from covariant density functional theory

Yuan Li, Hao-jie Xu, Dandan Zhang, Guo-Liang Ma

Comments 7 pages, 5 figures

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Relativistic $^{238}$U+$^{238}$U collisions have recently been used to extract the quadrupole shape of $^{238}$U. In this study, we employ state-of-the-art three-dimensional (3D) lattice covariant density functional theory (CDFT) with pairing correlations to calculate the density of uranium, including its octupole and hexadecaople deformations, as input for hydrodynamic simulations of these collisions. We find that while the CDFT density well describes elliptic flow, a clear mismatch emerges with transverse-momentum-related observables, indicating a tension in the effective quadrupole deformation. Furthermore, constraining the octupole deformation with triangular flow $v_{3}$ proves to be difficult due to significant sensitivity to the uncertain nuclear structure of the gold reference system. Our results underscore the necessity of realistic nuclear densities for both colliding species and highlight the need for further investigation of correlations related to both flow and transverse momentum to fully characterize nuclear deformation.

2602.02332 2026-02-03 cond-mat.str-el

Critical behavior and evidence of dimensional crossover in quasi-two-dimensional Li$_2$FeSiO$_4$

Waldemar Hergett, Kevin Ackermann, Erik Walendy, Sven Spachmann, Martin Jonak, Mahmoud Abdel-Hafiez, Maurits W. Haverkort, R. Klingeler

Journal ref Phys. Rev. B 113, 024435 (2026)

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We report thermal expansion and heat capacity studies on Li$_2$FeSiO$_4$ single crystals which enable us to investigate the critical behavior in the magnetically quasi-two-dimensional (2D) material. Pronounced $λ$-shaped anomalies at the magnetic ordering temperature $T_{\rm N}$ imply significant magneto-elastic coupling. Our analysis of both the thermal expansion and the specific heat data implies the crossover from 2D Ising-like behavior for $|(T-T_{\rm N})/T_{\rm N}|>0.3$ to 3D Ising behavior \rev{below $\simeq 1.3\times T_{\rm N}$. The 2D-like behavior is further supported by density functional calculations which show minimal dispersion perpendicular to the crystallographic $ac$ planes of the layered structure, thereby indicating the 2D nature of magnetism at higher temperatures.} Our results extend the available model materials of quasi-2D magnetism to a high-spin $S=2$ system with tetrahedrally coordinated Fe$^{2+}$-ions, thereby illustrating how magnetic order evolves in a 2D Ising-like system with orbital degrees of freedom.

2602.02330 2026-02-03 physics.space-ph

Geoelectric Field Caused by Flux Transfer Events in an Ionosphere-Coupled Vlasiator Simulation

Konstantinos Horaites, Markku Alho, Yann Pfau-Kempf, Urs Ganse, Abiyot Workayehu, Jonas Suni, Fasil Tesema, Liisa Juusola, Giulia Cozzani, Sanni Hoilijoki, Ivan Zaitsev, Shiva Kavosi, Minna Palmroth

Comments 28 pages, 7 figures, Supporting Information (1 figure and 3 movies) included in peer-reviewed submission to JGR

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We report on the relationship between flux transfer events (FTEs) at Earth's magnetopause and the geoelectric field that is induced near the FTEs' magnetic footpoints. We study this system using the global hybrid-Vlasov code Vlasiator, which has recently been extended to model ionospheric physics. We also highlight the significance of 3D magnetic null points, which in our simulation can separate the FTEs into multiple flux ropes. Near the null points, the coiled FTE magnetic field lines are rerouted towards Earth, so that the magnetic footpoints are planted near the Region 1 ionospheric current system. The helicities of the flux ropes are organized by the y-component (GSE) of the magnetic field at the Earth's magnetopause. This occurs in our simulation due to the absence of a y-component of the interplanetary magnetic field, which would normally supply the FTE guide field that determines the helicity. We observe Alfvenic, Earthward-flowing field-aligned currents generated near the magnetopause that correlate with the passage of FTEs nearby. These pulses of current coincide with the formation of rotational geoelectric field structures, that appear near the noon meridian and propagate around the auroral oval towards the nightside.

2602.02327 2026-02-03 nucl-ex

Statistical properties of $^{133}$Xe and the $^{132}$Xe$(n,γ)$ cross section

H. C. Berg, V. W. Ingeberg, S. Siem, M. Wiedeking, D. L. Bleuel, A. Ratkiewicz, A. A. Avaa, T. D. Bucher, M. V. J. Chisapi, A. Görgen, P. Jones, B. V. Kheswa, K. L. Malatji, S. H. Mthembu, G. O'Neill, P. Papka, L. Pellegri, T. Seakamela, O. Shirinda, B. R. Zikhali

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$^{133}$Xe is an interesting case for plasma physics to explore nuclear excitation by electron capture, as the process can be studied using statistical properties of $^{133}$Xe. In this work we present results on $^{133}$Xe from the inverse-Oslo method where we extract the nuclear level density and the $γ$-strength function, which is used to calculate the (n,$γ$) cross section on $^{132}$Xe. The $γ$-strength function of $^{133}$Xe can constrain the estimated decay rate from nuclear excitation by electron capture. The $\mathrm{d}(^{132}\mathrm{Xe},\mathrm{p})^{132}\mathrm{Xe}$ reaction was used to create the compound nucleus $^{133}$Xe, which was recorded with an annular particle telescope and a scintillator array consisting of \la and BGO-shielded HPGe Clover detectors. With the inverse-Oslo method, it is possible to study nuclei that are impossible or unable to manufacture targets from, short lived isotopes, or as in this work, noble gases. We present the extracted nuclear level density, and $γ$-strength function for $^{133}$Xe, along with shell-model calculations of the statistical properties of $^{133}$Xe. These are the first statistical properties extracted below 6 MeV for any xenon isotope. We constrain the $^{132}$Xe(n,$γ$) $^{133}$Xe cross section and reaction rate using the TALYS reaction code.

2602.02323 2026-02-03 astro-ph.GA

PRISMS. UNCOVER-26185, a metal-poor SFG at z=10.05 with no evidence for a X-ray-luminous AGN

J. Álvarez-Márquez, L. Colina, A. Crespo-Gomez, S. Kendrew, J. Zavala, R. Marques-Chaves, C. Prieto-Jiménez, Abdurro'uf, C. Blanco-Prieto, L. A. Boogaard, M. Castellano, A. Fontana, Y. Fudamoto, S. Fujimoto, M. García-Marín, Y. Harikane, S. Harish, T. Hashimoto, T. Hsiao, E. Iani, A. K. Inoue, D. Langeroodi, R. Lin, J. Melinder, L. Napolitano, G. Ostlin, P. G. Pérez-González, P. Rinaldi, B. Rodríguez Del Pino, P. Santini, Y. Sugahara, T. Treu, A. Varo-O'ferral, G. Wright

Comments 14 pages, 5 figures, submitted to A&A

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This work presents the first results of the PRImordial galaxy Survey with MIRI Spectroscopy (PRISMS), a JWST cycle 4 program (PID 8051) aimed at the characterization of a relatively large sample of ten galaxies about 500 Myr after the Big Bang. Here, we present deep (13.9 hours) spectroscopy with the MIRI LRS of the lensed galaxy UNCOVER-26185 at a redshift of z=10.054. It is a faint UV galaxy (UV absolut magnitude of -18.83 mag) previously identified as a X-ray luminous AGN. MIRI LRS detects the H$β$+[OIII]4960,5008 complex and H$α$ emission line with a significance of 10$σ$ and 8$σ$, respectively, as well as the optical continuum emission at rest-frame 0.45 $μ$m and 0.57 $μ$m with a signal-to-noise ratio of 6-7. The UV-to-optical spectral energy distribution, combining continuum and emission lines, is compatible with: (i) a low stellar (A$_V$= 0.2) and nebular (A$_V$=0.0) extinction, (ii) a SFH composed by a young (7 Myr) starburst and an intermediate-age (65 Myr) stellar population, and (iii) a total stellar mass of 1.7$\times$10$^{8}$ M$_{\odot}$. The H$α$-derived star-formation rate is 1.3 M$_{\odot}$ yr$^{-1}$. The low optical emission line ratios locate UNCOVER-26185 as the most metal-poor (Z = 0.04 Z$_{\odot}$), and as outlier with the lowest ionization (logU=-2.5) galaxy identified so far at redshifts above 9. With no evidence of an active galactic nuclei in the rest-frame UV-to-optical spectrum, UNCOVER-26185 has the properties of a metal-poor, main-sequence star-forming galaxy at redshift 10, with ISM and ionization properties very different than those of the already studied UV-bright galaxies at redshifts beyond 10. PRISMS is starting to explore the population of intermediate-UV luminosity galaxies at z=10, covering UV absolute magnitudes in the range of -17.9 to -20.5, fainter than those of UV-bright galaxies studied so far.