Peer Revenue Publish or profit

Papers

Fresh from arXiv, typeset properly. Highlighted words trade on the market.

Physics

Watch Physics

Wednesday 2 September

Mathematical Physics

Ruelle–Pollicott Theory for Metastable Systems: A Unified Framework for Tipping Transitions

Mickaël D. Chekroun and Valerio Lucarini

Tipping points—abrupt, potentially irreversible reorganizations of a system's statistical state—are commonly anticipated through critical slowing down: recovery slows, autocorrelation and variance rise, and spectra redden. This paradigm is powerful near simple equilibrium bifurcations but is not a general theory for stochastic, multistable, or metastable systems. We develop such a theory from the Ruelle–Pollicott (RP) spectrum of Kolmogorov generators of hypoelliptic Itô diffusions. Resolving the sensitivity of invariant statistics on RP spectral blocks shows that each contribution factorizes into a spectral denominator and a residue coupling the block to both the observable and perturbation direction. Small denominators permit large responses; residues produce them. Thus a closing RP gap is not sufficient for an early warning, while growing residues can generate the classical signature with no gap closure. An early-warning signal is therefore a property of a triple: RP block, observable, and perturbation direction. We demonstrate this on a stochastic non-normal system whose RP spectrum is exactly frozen, yet classical indicators become more alarming than during genuine gap closure. The RP decomposition attributes this to residue growth and yields an index $\mathcal{N}(f)$ satisfying $\mathcal{N}(f)\leq 1$ for reversible dynamics; hence $\mathcal{N}(f)>1$ certifies residue-driven amplification. For metastable systems, one killed problem yields two complementary spectral objects: the Doob $Q$-process isolates in-well recovery, while escape clocks and committor-weighted destination probabilities govern interwell transitions. In a one-dimensional fold, these scale as $(\epsilon_c-\epsilon)^{1/2}$ and $(\epsilon_c-\epsilon)^{3/2}$, separating bifurcation-induced from noise-induced tipping. Doob drift also connects to optimal Girsanov sampling.
Read the full abstract

Statistical Mechanics

Thermodynamic optimization of thermal landscapes and energy barriers in a Brownian heat engine

Mesfin Taye

Spatial temperature fields in Brownian heat engines are commonly prescribed a priori, and the resulting transport and thermodynamic properties are then calculated. Here we formulate the complementary inverse-design problem: determining the temperature profile and barrier height that optimize a chosen thermodynamic objective. We consider an overdamped Brownian particle in a symmetric triangular periodic potential under a constant opposing load and derive the exact stationary current and probability density for an arbitrary bounded temperature field, $\Tc\le T(x)\le\Th$. In the quasistatic limit, the efficiency becomes an exact functional of two inverse-temperature integrals over the uphill and downhill branches. Its rigorous global maximum under the pointwise temperature bounds is $\eta_{\max}=1-\Tc/\Th$, attained uniquely, up to sets of measure zero, by the hot-uphill/cold-downhill piecewise-constant profile. At finite current, however, the optimization changes qualitatively because the current is determined jointly by the cycle affinity and a nonlocal transport resistance. We derive the exact functional gradient and the corresponding box-constrained optimality conditions, showing that the current- or power-maximizing profile generally differs from the quasistatic efficiency optimum. For any prescribed temperature field, the current-maximizing barrier satisfies an exact balance between the marginal gain in thermal rectification and the marginal increase in transport resistance, with the characteristic estimate $U_0^*\simeq T_{\rm act}$, where $T_{\rm act}^{-1}=(2/L)\int_0^{L/2}\dd x/T(x)$.
Read the full abstract

Soft Condensed Matter

The Universal Role of Fragility on the Yielding Transition of Active Glass under Oscillatory Shear

Arnab Mandal, Roni Chatterjee and Smarajit Karmakar

The yielding transition marks the onset of irreversible plastic deformation in amorphous solids and plays a central role in determining the mechanical stability and failure of metallic glasses, colloidal suspensions, and biological assemblies. Despite extensive research, the microscopic factors governing the nature of yielding, particularly the transition between brittle and ductile mechanical responses, remain poorly understood. Recent studies have identified kinetic fragility as a key parameter governing yielding in passive glasses; whether this connection persists in active glasses remains open. Here, using molecular dynamics simulations of a Kob-Andersen glass former doped with Run-and-Tumble (RTP) active particles under oscillatory shear, we show that activity systematically reduces kinetic fragility and consequently alters the mechanical response. The common yield point $\gamma_c$ decreases monotonically with activity and exhibits a power-law dependence on the Arrhenius activation barrier. Increasing activity suppresses the dependence of the yield strain on thermal history and transforms the response from brittle-like to increasingly ductile, with smoother stress relaxation and reduced stress discontinuities. The timescale to reach steady state near yielding retains a critical power-law divergence, indicating that activity does not alter the underlying critical character of the transition. Active glasses also develop broader, more diffuse shear bands. Our results establish kinetic fragility as a unifying parameter governing yielding in both passive and active glasses and demonstrate that activity offers a powerful route to tune the mechanical response of amorphous materials.
Read the full abstract

High Energy Physics (Phenomenology)

Dark Matter at the Kinematic Edge: Interpreting the 248 keV LZ Nuclear-Recoil Candidate

Mattia Di Mauro

The LUX-ZEPLIN (LZ) Collaboration recently reported one event consistent with a $248$ keV nuclear recoil in a $2.84$ tonne-year exposure, with a maximum local significance of $3.4\sigma$ and a global significance of $2.6\sigma$. We investigate whether the dark matter (DM)–nucleon interactions favored by this high-energy event can arise from particle DM models that simultaneously reproduce the observed relic abundance and satisfy indirect-detection constraints. Using the published LZ efficiency and operator significances, we show that elastic spin-independent (SI) scattering poorly explains an isolated high-energy recoil because its spectrum is concentrated at lower energies, whereas elastic spin-dependent (SD) $\mathcal{O}_4$ scattering remains viable. Endothermic scattering instead naturally suppresses the low-energy rate and shifts the recoil spectrum toward the observed energy. A thermal pseudo-Dirac fermion with an off-diagonal vector interaction provides a simple realization of this mechanism. For $m_\chi\simeq1$ TeV, the relic-density requirement predicts $\sigma_N\simeq6.5\times10^{-43}\,\mathrm{cm}^2$, while a splitting $\delta\simeq297$ keV shifts the recoil spectrum into the LZ event region. Present-day indirect-detection signals can be strongly suppressed because freeze-out proceeds mainly through coannihilation, while the excited state is depleted at late times. A thermal Higgsino provides a more predictive realization: its relic abundance fixes the mass near $1.1$ TeV, while a splitting $\delta\simeq 377$ keV is required to reproduce the event. This interpretation is testable through the associated gamma-ray line signal. Overall, combining direct detection, relic density, and indirect detection significantly restricts the viable interpretations of the LZ event and provides concrete targets for future searches.
Read the full abstract

Optics

Spatially-resolved multiphoton photoemission from a lateral transition metal dichalcogenide heterostructure

Lina Hansen, Paul Martin, Sai Shradha et al. (+7 more)

Transition metal dichalcogenides (TMDs) in their monolayer form offer a premier platform for next-generation optoelectronics, particularly through the local manipulation of their robust excitonic states using nanoscale electric fields. These localized states can be dynamically controlled through spatial structuring as well as through ultrafast field modulations driven by tailored optical pulses. Characterizing the resulting rapid, nanoscale charge carrier dynamics requires a technique with exceptional spatial and temporal resolution. Here, we report on the spatio-temporally resolved investigation of ground state and excited state photoemission from a lateral heterostructure built of monolayers of WSe$_2$ and MoSe$_2$ using few-cycle light pulses with a photon energy of 0.62 eV. We utilize photoemission electron microscopy to spatially resolve the highly nonlinear photoemission from the monolayer structure with few tens of nanometer resolution. By varying the laser pulse energy, we extract the nonlinearity of the photoemission process and thus the dynamic binding energy of the photoelectrons before and after optical excitation with high spatial and temporal resolution.
Read the full abstract

All authors Lina Hansen, Paul Martin, Sai Shradha, Julian Picker, Arvid Klösgen, Kerstin Harland, Katrin Meier, Andrey Turchanin, Bernhard Urbaszek, Jan Vogelsang

High Energy Physics (Phenomenology)

$D\rightarrow \pi$ transitions from QCD Light-Cone Sum Rules with the chiral currents

Di Gao, Jiangshan Lan, Duojie Jia et al. (+2 more)

We present a systematic study of the transition form factors for the semileptonic decays $D\rightarrow Pe^{+}v_{e}$ and $D\rightarrow P\mu^{+}\bar{v}_{\mu}$ using QCD light-cone sum rules with chiral currents, with emphasis on the nonperturbative structure of the pion. The distribution amplitudes of the meson $\pi$, including twist-2 and higher-twist components, are analyzed and incorporated in our computation, employing both Gegenbauer polynomial expansions and the Basis Light-Front Quantization (BLFQ) method, where the latter yields a distribution that rapidly converges to the asymptotic form. Two relations linking transition form factors are derived and found to be consistent with the chiral symmetry of QCD. Our numerical predictions for the $D$-to-pion form factors agee well with BES\uppercase\expandafter{\romannumeral3} measurements and lattice QCD calculations. Furthermore, the differential decay widths obtained thereby for the $D$-to-pion decay also show consistency with the BES\uppercase\expandafter{\romannumeral3} data in the high-momentum-transfer ($q$) region with the $q^{2}>1\ \rm{GeV^2}$, implying new opportunities for the precise extraction of the CKM matrix element and the exploration of physics beyond the Standard Model.
Read the full abstract

All authors Di Gao, Jiangshan Lan, Duojie Jia, Xingbo Zhao, Yanjun Sun

Earth and Planetary Astrophysics

Drift-dominated dust evolution. A multiwavelength analysis of dust rings in CY Tau and DoAr25

Anastasia Topalidou, Nienke van der Marel, Paola Pinilla et al. (+3 more)

Context. Protoplanetary disks are the birthplaces of planets, and understanding the distribution and evolution of dust within them is essential for tracing the early stages of planet formation. Aims. Following the DSHARP survey, we aim to constrain the radial distribution of the dust surface density and the maximum emitting grain size in the disks of CY Tau and DoAr 25 and assess the relative importance of dust trapping and radial drift in shaping the dust population in disks. Methods. We present multiwavelength continuum observations of CY Tau and DoAr 25 from ALMA at 2.4 and 1.25 mm and archival VLA data at 8.8 mm. Combining the observations with dust continuum forward modeling, we sought to infer a radial profile of the two systems of the dust surface density and maximum emitting grain size. Results. For DoAr 25, the results reveal a prominent dust ring at 111 AU and evidence for large (centimeter-sized) grains extending to the outer disk. In contrast, CY Tau exhibits a more compact and smoother structure, with both the dust surface density and grain size decreasing monotonically with radius. A tentative shoulder feature in the radial profiles, located between 20-40 AU, may point to a marginal substructure, possibly a weak dust trap. Conclusions. DoAr 25 shows evidence for a dust trap capable of halting inward drift, while CY Tau exhibits behavior consistent with evolution dominated by radial drift. Together, these results highlight how dust evolution processes shape the disk morphology and grain-size distributions, even in the low-mass stellar regime.
Read the full abstract

All authors Anastasia Topalidou, Nienke van der Marel, Paola Pinilla, Haochang Jiang, Osmar M. Guerra-Alvarado, Brodie J. Norfolk

Soft Condensed Matter

Multivariate hyperdensity functional theory for inhomogeneous equilibrium fluids: From first principles to simulation-based machine learning

Florian Sammüller and Matthias Schmidt

Hyperdensity functional theory facilitates the investigation of the equilibrium behavior of a general order parameter or statistical mechanical observable in spatially inhomogeneous classical many-body systems. The approach is based on applying the exact Mermin-Evans classical density functional mapping to an extended ensemble. Here we present the multivariate generalization for investigating simultaneously the properties and interrelations of several different hyperobservables of choice. The resulting framework gives rise to a systematic characterization and prediction scheme for general many-body phenomena. All pertinent equilibrium averages, variances, and covariances constitute universal density functionals, as we demonstrate explicitly. Associated one-body hyperfluctuation profiles quantify the degree of correlation of the local density with first- and second-order combinations of hyperobservables. These multivariate hyperfluctuation profiles are accessible in many-body simulations and they satisfy exact hyper-Ornstein-Zernike equations, which we derive from the minimization principle in the extended multivariate ensemble. The formal structure of the theory integrates naturally with supervised machine learning, which renders all hyperdensity functionals accessible in practice via training of neural networks on simulation data. We demonstrate all salient techniques using the illustrative case of clustering in confined hard rod fluids, thereby choosing the total number of particles and the largest cluster size as the representative hyperobservables of interest. Our numerical methodology enables the efficient and successful prediction of all statistical quantities induced by the chosen hyperobservables, which we verify via comparison to test data and which we attribute to the tight interplay of first-principles and machine-learning concepts that our general approach combines.
Read the full abstract

Quantum Physics

The advantages of extended nonreciprocal quantum batteries

Meng-Long Song, Zan Cao, Hai-Tao Dong et al. (+4 more)

This study investigates the performance of extended nonreciprocal quantum batteries (QBs), as well as its advantages in energy storage and energy transfer compared to reciprocal charging and the original nonreciprocal batteries. After analyzing the detuning between the charging system and the external pump, we discover that resonance is a key factor in maintaining high-energy batteries and high charging power; furthermore, the detuning of the charger or battery determines the stability of the charging process for different structures. Research on steady-state energy storage in batteries revealed that single-threaded or multi-threaded charging can achieve nearly infinite energy storage in weakly localized environments, thereby demonstrating the significant energy advantages of extended nonreciprocal quantum batteries. Finally, by considering the energy distribution within the charging system, we observe that nonreciprocal charging offers energy transfer advantages unmatched by reciprocal charging; the former achieves a comprehensive balance between charging cost and energy storage capacity that the latter cannot match. As a novel and superior charging protocol, our findings are expected to provide a potent reference for the promotion and practical implementation of nonreciprocal charging.
Read the full abstract

All authors Meng-Long Song, Zan Cao, Hai-Tao Dong, Si-Yu Zhang, Xue-Ke Song, Liu Ye, Dong Wang

Optics

Exceptional Topological Signatures of Non-Hermitian Photonic Hopf-Link Braids

Samit Kumar Gupta

Non-Hermitian physics endows the non-Abelian systems with exceptional topology characterized by non-commutative braid patterns. Interplay of distinct competing sources of non-Hermiticity may induce novel topological effects. Here, we provide a generalized Hatano-Nelson model with higher-order nonreciprocal hoppings, non-Abelian gauge fields, and staggered gain-loss processes showing the exceptional topological structure of the Hopf-link braids that undergoes a EP-mediated topological phase transition. We demonstrate that mixing multiple nonreciprocal channels drives the system into highly intricate, nested complex energy Hopf-link braids and expands the topological landscape up to higher-order braiding sectors. Furthermore, utilizing biorthogonal eigenvector tracking, we map the structural evolution of the exceptional phase boundaries via the maximum Petermann factor in the phase angle parameter planes. We show that the gain-loss non-Hermiticity drives a topological crossover where the extended exceptional contours constrict into isolated regimes. The demonstration of EP-mediated topological phase transition of Hopf-link braids and the associated rich exceptional phase portraits may offer new physical insights with promising applications in robust, fault-tolerant communication channels and quantum computing platforms.
Read the full abstract

Statistical Mechanics

Memory-driven Topological Defects and Unconventional Long-Range Order

Ziyang Ding and Zi Cai

We investigate many-body systems with time-delayed self-interactions mediated by a memory-feedback mechanism. We show that such temporal interactions generate non-equilibrium orders and unique topological defects absent in equilibrium-specifically, helical vortices wherein opposite vorticities propagate in reverse directions along domain walls. In one dimension, memory feedback stabilizes true long-range order against weak noise, thereby circumventing the Mermin-Wagner theorem and resulting in an unconventional finite-temperature phase transition with a dynamical exponent $z = 4$. Physical realizations of these memory-driven non-equilibrium systems using active mechatronic metamaterials has also been proposed. These results demonstrate engineered temporal interactions as a powerful paradigm for non-equilibrium many-body physics.
Read the full abstract

High Energy Physics (Experiment)

Measurement of inelastic scattering $\Lambda(\overline{\Lambda})+p\to\Sigma^{0}(\overline{\Sigma}^{0})+p$ via $e^+e^-\to J/\psi\to\Lambda\overline{\Lambda}$

BESIII Collaboration: M. Ablikim, M. N. Achasov, P. Adlarson et al. (+774 more)

Using a sample of $(10087\pm44)\times10^{6}$ $J/\psi$ events collected with the BESIII detector, we investigate the inelastic scattering processes $\Lambda+p\to\Sigma^{0}+p$ and $\overline{\Lambda}+p\to\overline{\Sigma}^{0}+p$, exploiting hyperons from $J/\psi\to\Lambda\overline{\Lambda}$ decays as an effective beam and the beam-pipe materials as targets. The processes $\Lambda+{}^{9}\mathrm{Be}\to\Sigma^{0}+p+{}^{8}\mathrm{Li}$ and $\overline{\Lambda}+{}^{9}\mathrm{Be}\to\overline{\Sigma}^{0}+p+{}^{8}\mathrm{Li}$ are measured at a hyperon momentum of $1.074~\mathrm{GeV}/c$, with cross sections of $(10.1\pm1.4_{\rm stat}\pm0.7_{\rm syst})$ mb and $(1.7\pm0.6_{\rm stat}\pm0.4_{\rm syst})$ mb, respectively. Under the assumption of surface-dominated hyperon-nucleus scattering, these measurements are used to extract the corresponding proton-target cross sections. Independently, direct measurements using the hydrogen component of the beam-pipe oil yield $(3.2\pm1.1_{\rm stat}\pm0.5_{\rm syst})$ mb for $\Lambda+p\to\Sigma^{0}+p$ and $(1.5\pm0.5_{\rm stat}\pm0.1_{\rm syst})$ mb for $\overline{\Lambda}+p\to\overline{\Sigma}^{0}+p$, consistent with the indirect determinations. The combined cross sections are $(4.7\pm0.7)$ mb and $(1.1\pm0.3)$ mb, respectively. The $\overline{\Lambda}+p\to\overline{\Sigma}^{0}+p$ signal constitutes the first evidence for anti-hyperon inelastic scattering with baryonic final states, with a significance of $3.1\sigma$. The pronounced difference between the $\Lambda p$ and $\overline{\Lambda}p$ inelastic scattering cross sections provides new experimental constraints on hyperon-nucleon and anti-hyperon-nucleon interactions.
Read the full abstract

All authors BESIII Collaboration: M. Ablikim, M. N. Achasov, P. Adlarson, X. C. Ai, C. S. Akondi, R. Aliberti, A. Amoroso, Q. An, M. S. Anderson, Y. Bai, O. Bakina, H. R. Bao, X. L. Bao, M. Barbagiovanni, V. Batozskaya, K. Begzsuren, N. Berger, M. Berlowski, M. B. Bertani, D. Bettoni, F. Bianchi, E. Bianco, A. Bortone, I. Boyko, R. A. Briere, A. Brueggemann, D. Cabiati, H. Cai, M. H. Cai, X. Cai, A. Calcaterra, G. F. Cao, N. Cao, S. A. Cetin, X. Y. Chai, J. F. Chang, T. T. Chang, G. R. Che, Y. Z. Che, C. H. Chen, Chao Chen, G. Chen, H. S. Chen, H. Y. Chen, M. L. Chen, S. J. Chen, S. M. Chen, T. Chen, W. Chen, X. R. Chen, X. T. Chen, X. Y. Chen, Y. B. Chen, Y. Q. Chen, Z. K. Chen, J. Cheng, L. N. Cheng, S. K. Choi, X. Chu, G. Cibinetto, F. Cossio, J. Cottee-Meldrum, H. L. Dai, J. P. Dai, X. C. Dai, A. Dbeyssi, R. E. de Boer, D. Dedovich, C. Q. Deng, Z. Y. Deng, A. Denig, I. Denisenko, M. Destefanis, F. De Mori, E. Di Fiore, X. X. Ding, Y. Ding, Y. X. Ding, J. Dong, L. Y. Dong, M. Y. Dong, X. Dong, Z. J. Dong, M. C. Du, S. X. Du, Shaoxu Du, X. L. Du, Y. Q. Du, Y. Y. Duan, Z. H. Duan, P. Egorov, G. F. Fan, J. J. Fan, K. X. Fan, Y. H. Fan, J. Fang, Jin Fang, S. S. Fang, W. X. Fang, Y. Q. Fang, L. Fava, F. Feldbauer, G. Felici, C. Q. Feng, J. H. Feng, Q. X. Feng, Y. T. Feng, M. Fritsch, C. D. Fu, J. L. Fu, Y. W. Fu, H. Gao, Xu Gao, Y. Gao, Y. N. Gao, Y. Y. Gao, Yunong Gao, Z. Gao, S. Garbolino, I. Garzia, L. Ge, P. T. Ge, Z. W. Ge, C. Geng, A. Gilman, K. Goetzen, J. Gollub, J. B. Gong, J. D. Gong, L. Gong, W. X. Gong, W. Gradl, M. Greco, M. D. Gu, M. H. Gu, C. Y. Guan, A. Q. Guo, H. Guo, J. N. Guo, L. B. Guo, M. J. Guo, R. P. Guo, X. Guo, Y. P. Guo, Z. Guo, A. Guskov, J. Gutierrez, J. Y. Han, T. T. Han, X. Han, F. Hanisch, J. Y. Hao, K. D. Hao, X. Q. Hao, F. A. Harris, C. Z. He, K. K. He, K. L. He, F. H. Heinsius, C. H. Heinz, Y. K. Heng, C. Herold, P. C. Hong, G. Y. Hou, X. T. Hou, Y. R. Hou, Z. L. Hou, H. M. Hu, J. F. Hu, Q. P. Hu, S. L. Hu, T. Hu, Y. Hu, Y. X. Hu, Z. M. Hu, G. S. Huang, K. X. Huang, L. Q. Huang, P. Huang, X. T. Huang, Y. P. Huang, Y. S. Huang, T. Hussain, N. Hüsken, N. in der Wiesche, J. Jackson, Q. Ji, Q. P. Ji, W. Ji, X. B. Ji, X. L. Ji, Y. Y. Ji, L. K. Jia, X. Q. Jia, D. Jiang, S. J. Jiang, X. S. Jiang, Y. Jiang, J. B. Jiao, J. K. Jiao, Z. Jiao, L. C. L. Jin, S. Jin, Y. Jin, M. Q. Jing, X. M. Jing, T. Johansson, S. Kabana, X. L. Kang, X. S. Kang, B. C. Ke, V. Khachatryan, A. Khoukaz, O. B. Kolcu, B. Kopf, L. Kröger, L. Krümmel, Y. Y. Kuang, M. Kuessner, X. Kui, N. Kumar, A. Kupsc, W. Kühn, Q. Lan, W. N. Lan, T. T. Lei, M. Lellmann, T. Lenz, C. Li, C. H. Li, C. K. Li, Cong Li, D. M. Li, F. Li, G. Li, H. B. Li, H. J. Li, H. L. Li, H. N. Li, H. P. Li, Hui Li, J. N. Li, J. S. Li, J. W. Li, K. Li, K. L. Li, L. J. Li, L. K. Li, Lei Li, M. H. Li, M. R. Li, M. T. Li, P. L. Li, P. R. Li, Q. M. Li, Q. X. Li, R. Li, S. Li, S. X. Li, S. Y. Li, Shanshan Li, T. Li, T. Y. Li, W. D. Li, W. G. Li, X. Li, X. H. Li, X. K. Li, X. L. Li, X. Y. Li, X. Z. Li, Y. Li, Y. H. Li, Y. B. Li, Y. C. Li, Y. G. Li, Y. P. Li, Yi Li, Z. H. Li, Z. J. Li, Z. L. Li, Z. X. Li, Z. Y. Li, Zaiyi Li, C. Liang, H. Liang, Y. F. Liang, Y. T. Liang, Z. Z. Liang, G. R. Liao, L. B. Liao, M. H. Liao, Y. P. Liao, J. Libby, A. Limphirat, C. C. Lin, C. X. Lin, D. X. Lin, T. Lin, B. J. Liu, B. X. Liu, C. Liu, C. X. Liu, F. Liu, F. H. Liu, Feng Liu, G. M. Liu, H. Liu, H. B. Liu, H. M. Liu, Huihui Liu, J. B. Liu, K. Liu, K. Y. Liu, Ke Liu, Kun Liu, L. Liu, L. C. Liu, Lu Liu, M. H. Liu, P. L. Liu, Q. Liu, S. B. Liu, T. Liu, W. M. Liu, W. T. Liu, X. Liu, X. K. Liu, X. L. Liu, X. P. Liu, X. T. Liu, X. Y. Liu, Y. Liu, Y. B. Liu, Yi Liu, Z. A. Liu, Z. D. Liu, Z. Q. Liu, Z. X. Liu, Z. Y. Liu, Ziqiang Liu, X. C. Lou, H. J. Lu, J. G. Lu, X. L. Lu, Y. Lu, Y. H. Lu, Y. P. Lu, Z. H. Lu, C. L. Luo, J. R. Luo, J. S. Luo, M. X. Luo, T. Luo, X. L. Luo, Z. Y. Lv, X. R. Lyu, Y. F. Lyu, Y. H. Lyu, C. L. Ma, F. C. Ma, H. L. Ma, Heng Ma, J. L. Ma, L. L. Ma, L. R. Ma, Q. M. Ma, R. Q. Ma, R. Y. Ma, T. Ma, X. T. Ma, X. Y. Ma, F. E. Maas, I. MacKay, M. Maggiora, S. Maity, S. Malde, Y. J. Mao, Z. P. Mao, S. Marcello, A. Marshall, F. M. Melendi, Y. H. Meng, Z. X. Meng, G. Mezzadri, H. Miao, T. J. Min, R. E. Mitchell, X. H. Mo, B. Moses, N. Yu. Muchnoi, J. Muskalla, Y. Nefedov, F. Nerling, H. Neuwirth, Z. Ning, S. Nisar, Q. L. Niu, W. D. Niu, Y. Niu, C. Normand, S. L. Olsen, Q. Ouyang, I. V. Ovtin, S. Pacetti, Y. Pan, C. Y. Pang, A. Pathak, Y. P. Pei, M. Pelizaeus, G. L. Peng, H. P. Peng, X. J. Peng, Y. Y. Peng, K. Peters, K. Petridis, J. L. Ping, R. G. Ping, S. Plura, V. Prasad, L. Pöpping, F. Z. Qi, H. R. Qi, L. Y. Qian, S. Qian, W. B. Qian, C. F. Qiao, J. H. Qiao, J. J. Qin, J. L. Qin, L. Q. Qin, L. Y. Qin, P. B. Qin, X. P. Qin, X. S. Qin, Z. H. Qin, J. F. Qiu, Z. H. Qu, J. Rademacker, K. Ravindran, C. F. Redmer, A. Rivetti, M. Rolo, G. Rong, S. S. Rong, F. Rosini, Ch. Rosner, M. Q. Ruan, W. R. Ruangyoo, N. Salone, A. Sarantsev, Y. Schelhaas, M. Schernau, K. Schoenning, M. Scodeggio, W. Shan, X. Y. Shan, Z. J. Shang, J. F. Shangguan, L. G. Shao, M. Shao, C. P. Shen, H. F. Shen, W. H. Shen, X. Y. Shen, B. A. Shi, Ch. Y. Shi, H. Shi, J. L. Shi, J. Y. Shi, M. H. Shi, S. Shi, S. Y. Shi, X. Shi, H. L. Song, J. J. Song, M. H. Song, T. Z. Song, W. M. Song, Zirong Song, S. Sosio, S. Spataro, S. Stansilaus, F. Stieler, M. Stolte, S. S Su, G. B. Sun, G. X. Sun, H. Sun, H. K. Sun, J. F. Sun, K. Sun, L. Sun, R. Sun, S. S. Sun, T. Sun, W. Y. Sun, Y. C. Sun, Y. H. Sun, Y. J. Sun, Y. Z. Sun, Z. Q. Sun, Z. T. Sun, H. Tabaharizato, N. T. Tagsinsit, C. J. Tang, G. Y. Tang, J. Tang, J. J. Tang, L. F. Tang, Y. A. Tang, Z. H. Tang, L. Y. Tao, M. Tat, J. X. Teng, J. Y. Tian, W. H. Tian, Y. Tian, Z. F. Tian, K. Yu. Todyshev, I. Uman, E. van der Smagt, B. Wang, Bin Wang, Bo Wang, C. Wang, Chao Wang, Cong Wang, D. Y. Wang, F. K. Wang, H. J. Wang, H. R. Wang, J. Wang, J. H. Wang, J. J. Wang, J. P. Wang, K. Wang, L. L. Wang, L. W. Wang, M. Wang, Mi Wang, N. Y. Wang, S. Wang, Shun Wang, T. Wang, W. Wang, W. P. Wang, X. F. Wang, X. L. Wang, X. N. Wang, Xin Wang, Y. Wang, Y. D. Wang, Y. F. Wang, Y. H. Wang, Y. J. Wang, Y. L. Wang, Y. N. Wang, Yanning Wang, Yaqian Wang, Yi Wang, Yuan Wang, Z. Wang, Z. L. Wang, Z. Q. Wang, Z. Y. Wang, Zhi Wang, Ziyi Wang, D. Wei, D. H. Wei, D. J. Wei, H. R. Wei, F. Weidner, H. R. Wen, S. P. Wen, U. Wiedner, G. Wilkinson, M. Wolke, J. F. Wu, L. H. Wu, L. J. Wu, Lianjie Wu, S. G. Wu, S. M. Wu, X. W. Wu, Z. Wu, H. L. Xia, L. Xia, B. H. Xiang, D. Xiao, G. Y. Xiao, H. Xiao, Y. L. Xiao, Z. J. Xiao, C. Xie, K. J. Xie, Y. Xie, Y. G. Xie, Y. H. Xie, Z. P. Xie, T. Y. Xing, D. B. Xiong, G. F. Xu, H. Y. Xu, Q. J. Xu, Q. N. Xu, T. D. Xu, X. P. Xu, Y. Xu, Y. C. Xu, Z. S. Xu, F. Yan, L. Yan, W. B. Yan, W. C. Yan, W. H. Yan, W. P. Yan, X. Q. Yan, Y. Y. Yan, H. J. Yang, H. L. Yang, H. X. Yang, J. H. Yang, L. Y. Yang, N. Yang, R. J. Yang, X. Y. Yang, Y. Yang, Y. G. Yang, Y. H. Yang, Y. M. Yang, Y. Q. Yang, Y. Z. Yang, Youhua Yang, Z. B. Yang, W. J. Yao, Z. P. Yao, M. Ye, M. H. Ye, Z. J. Ye, K. Yi, Junhao Yin, Z. Y. You, B. X. Yu, C. X. Yu, G. Yu, J. S. Yu, L. W. Yu, T. Yu, X. D. Yu, Y. C. Yu, Yongchao Yu, C. Z. Yuan, H. Yuan, J. Yuan, Jie Yuan, L. Yuan, M. K. Yuan, S. H. Yuan, Y. Yuan, C. X. Yue, Ying Yue, A. A. Zafar, F. R. Zeng, S. H. Zeng, X. Zeng, Y. J. Zeng, Yujie Zeng, Y. C. Zhai, Y. H. Zhan, B. L. Zhang, B. R. Zhang, B. X. Zhang, D. H. Zhang, G. Y. Zhang, Gengyuan Zhang, H. Zhang, H. C. Zhang, H. H. Zhang, H. L. Zhang, H. Q. Zhang, H. R. Zhang, H. Y. Zhang, Han Zhang, J. Zhang, J. J. Zhang, J. L. Zhang, J. Q. Zhang, J. S. Zhang, J. W. Zhang, J. X. Zhang, J. Y. Zhang, J. Z. Zhang, Jianyu Zhang, Jin Zhang, Jiyuan Zhang, L. M. Zhang, Lei Zhang, N. Zhang, P. Zhang, Q. Zhang, Q. Y. Zhang, Q. Z. Zhang, R. Y. Zhang, S. H. Zhang, S. N. Zhang, Shulei Zhang, X. M. Zhang, X. Y. Zhang, Y. T. Zhang, Y. H. Zhang, Y. P. Zhang, Yao Zhang, Yu Zhang, Yu Zhang, Z. Zhang, Z. D. Zhang, Z. H. Zhang, Z. L. Zhang, Z. R. Zhang, Z. X. Zhang, Z. Y. Zhang, Zh. Zh. Zhang, Zhaoke Zhang, Zhilong Zhang, Ziyang Zhang, Ziyu Zhang, G. Zhao, J.-P. Zhao, J. Y. Zhao, J. Z. Zhao, L. Zhao, Lei Zhao, M. G. Zhao, R. P. Zhao, Y. B. Zhao, Y. L. Zhao, Y. P. Zhao, Y. X. Zhao, Z. G. Zhao, A. Zhemchugov, B. Zheng, B. M. Zheng, J. P. Zheng, W. J. Zheng, W. Q. Zheng, X. R. Zheng, Y. H. Zheng, B. Zhong, C. Zhong, X. Zhong, H. Zhou, J. Q. Zhou, S. Zhou, X. Zhou, X. K. Zhou, X. R. Zhou, X. Y. Zhou, Y. X. Zhou, Y. Z. Zhou, A. N. Zhu, J. Zhu, K. Zhu, K. J. Zhu, K. S. Zhu, L. X. Zhu, Lin Zhu, S. H. Zhu, W. D. Zhu, W. J. Zhu, W. Z. Zhu, Y. C. Zhu, Z. A. Zhu, X. Y. Zhuang, M. Zhuge, J. H. Zou, J. Zu

Quantum Physics

Long-lived telecom-heralded single-photon storage in an absorptive spin-rephased quantum memory

Alberto E. Rodríguez-Moldes, Félicien Appas, Jonathan Hänni et al. (+3 more)

Long-lived storage of single photons under the form of atomic excitations is at the foundation of long-distance entanglement distribution in quantum networks. To mitigate decoherence effects induced by the environment, rephasing of the hyperfine coherences using microwave pulses have been implemented in a variety of single-emitter and ensemble-based solid-state systems. However, the demonstration of storage of single photons in an absorptive quantum memory including such spin rephasing mechanism remains elusive. In this work, we show non-classical storage of telecom-heralded single photons in a Pr$^{3+}$:Y$_2$SiO$_5$ rare-earth ion doped crystal quantum memory using the atomic frequency comb (AFC) spin-wave protocol combined with a XY4 spin rephasing sequence. Long-lived AFC photon echoes are first observed in the classical regime for storage times of up to approximately 3 ms. We then demonstrate non-classical correlations between heralding photons and stored signal photons generated by a cavity-enhanced parametric photon-pair source for storage times of up to 180 $\mu$s and with measured cross-correlation values as high as 4.6(4). Together with the capacity of Pr$^{3+}$:Y$_2$SiO$_5$ QMs to support highly efficient and multiplexed storage, this result represents a significant step towards scalable long-distance quantum repeater links.
Read the full abstract

All authors Alberto E. Rodríguez-Moldes, Félicien Appas, Jonathan Hänni, Jelena V. Rakonjac, Samuele Grandi, Hugues de Riedmatten

Instrumentation and Methods for Astrophysics

3.5-meter Segmented-Mirror Robotic Space Telescope Mission White Paper III. Key Scientific Mission: Exoplanet Science with a Coronagraph

Juhan Kim, Sang Hyun Lee, Yong-Woo Kang et al. (+22 more)

This volume defines the exoplanet science program enabled by the dedicated high-contrast coronagraph in the baseline science payload of the 3.5-meter Segmented-Mirror Robotic Space Telescope. The observatory architecture incorporates the optical interfaces, wavefront sensing and control, pointing stability, and operations software required for coronagraphic observations from the outset. The observing strategy gives priority to the nearest stellar systems because they provide the most accessible laboratories for planetary exploration and the most likely destinations of future interstellar missions. The diffraction limit sets a reflected-light horizon of roughly 10–15 pc for planets at 1 AU and roughly 50–80 pc for Jupiter analogs. Within those horizons, the telescope can image nearby giant planets, obtain reflected-light spectra of their atmospheres, survey young systems and circumstellar disks, and support the habitability and biosignature programs that larger future missions will pursue. The wide-field imager complements the coronagraph through transit photometry, occurrence-rate statistics, and long-term monitoring of stellar magnetic activity. A systematic census of the nearest stellar neighbors provides a lasting reference for exoplanet science and future space exploration.
Read the full abstract

All authors Juhan Kim, Sang Hyun Lee, Yong-Woo Kang, Jeong-Yeol Han, Sungwook E. Hong, Bongkon Moon, Donguk Song, Juhyung Kang, Myeong-Gu Park, Sang Chul Kim, Chung-Uk Lee, Sangmo Tony Sohn, Arman Shafieloo, David Parkinson, Hong Soo Park, Dohyeong Kim, Chan Park, Jungjoo Sohn, Young-Beom Jeon, Jong-Hak Woo, Hyung Mok Lee, Hong Bae Ann, Myungkook James Jee, Mansoo Choi, Changbom Park

Instrumentation and Methods for Astrophysics

3.5-meter Segmented-Mirror Robotic Space Telescope Mission White Paper II. Key Scientific Mission: Wide-Field Cosmology and Galaxy Evolution

Juhan Kim, Yong-Woo Kang, Sang Hyun Lee et al. (+22 more)

The 3.5-meter Segmented-Mirror Robotic Space Telescope uses an image slicer for all spectroscopic observations. The planning baseline uses $R \simeq 1000$ for the wide survey and retains selectable $R \simeq 5000$ bands for precision line measurements. The central science case is a dense emission-line galaxy redshift survey for baryon acoustic oscillations and redshift-space distortions. Supernova and quasar programs exploit the stability, multiplexing, and repeatability of space operations. The supernova tier measures rest-frame U and near-ultraviolet magnitudes that separate optical twins at subgroup precision to $z \simeq 0.9$–$1.1$ in standard visits and to $z \simeq 1.3$–$1.5$ in ten-hour stacks. Every wide-survey tile receives three spectroscopic orientations, and a joint scene reconstruction uses their different overlap geometries to recover the spectra. The flagship survey covers 100–300 deg$^2$ and targets $10^6$–$3 \times 10^6$ emission-line galaxies. A deep pencil-beam tier and a supernova time-domain tier complement the wide survey. The same observations provide a census of ultra-diffuse and low-surface-brightness galaxies, map intracluster light, and test cold, self-interacting, and fuzzy dark matter through dwarf-galaxy structure and low-mass halo abundance.
Read the full abstract

All authors Juhan Kim, Yong-Woo Kang, Sang Hyun Lee, Jeong-Yeol Han, Sungwook E. Hong, Bongkon Moon, Donguk Song, Juhyung Kang, Myeong-Gu Park, Sang Chul Kim, Chung-Uk Lee, Sangmo Tony Sohn, Arman Shafieloo, David Parkinson, Hong Soo Park, Dohyeong Kim, Chan Park, Jungjoo Sohn, Young-Beom Jeon, Jong-Hak Woo, Hyung Mok Lee, Hong Bae Ann, Myungkook James Jee, Mansoo Choi, Changbom Park

Quantum Gases

Magnetic-Field-Calibration-Free Determination of the Hyperfine Constant $A$ in Ultracold Fermi gases of $^{40}$K

Yajing Yang, Biao Shan, Yuhang Zhao et al. (+8 more)

Hyperfine constant $A$ is a key parameter of the hyperfine structure and underpins precision spectroscopy and metrology. In this Letter, we develop a magnetic-field-calibration-free method for determining the ground-state hyperfine constant $A$ in an ultracold $^{40}$K Fermi gas by utilizing a pair of magnetically insensitive ("clock") transitions. This overcomes the stringent magnetic-field calibration requirements of conventional methods. We measure the transition frequency between these two magnetically insensitive transitions with Hz-level resolution over a range of magnetic fields, and obtain the ground-state hyperfine constant $A = -h\times 285.730536(2)\,\mathrm{MHz}$, corresponding to an absolute uncertainty of about $2\,\mathrm{Hz}$. Our value reduces the uncertainty by nearly three orders of magnitude compared with previous determinations, providing a substantially improved reference for high-precision spectroscopy and metrology with $^{40}$K.
Read the full abstract

All authors Yajing Yang, Biao Shan, Yuhang Zhao, Jiahui Shen, Zhuxiong Ye, Liangchao Chen, Zengming Meng, Pengjun Wang, Wei Han, Jing Zhang, Lianghui Huang

Instrumentation and Methods for Astrophysics

3.5-meter Segmented-Mirror Robotic Space Telescope Mission White Paper I. Overall Architecture and Scientific Mission

Yong-Woo Kang, Sang Hyun Lee, Juhan Kim et al. (+22 more)

We present the preliminary science concept and mission architecture of a 3.5-meter segmented-mirror robotic space telescope currently under study. The observatory is conceived as a versatile platform supporting wide-field cosmology and galaxy evolution, direct imaging and characterization of nearby planetary systems, time-domain and multi-messenger observations, compact-object studies, and Solar-System small-body science. These programs share requirements for angular resolution, photometric stability, rapid target acquisition, spectroscopy, and long-term observing efficiency. The telescope employs an 18-segment 3.5-meter primary mirror for high-angular-resolution imaging from the near-ultraviolet through the optical and near-infrared. The current baseline covers 0.2–1.5 $\mu$m, with the wavelength for diffraction-limited performance to be set by the final wavefront-error budget. Wide-field imaging is intended for deep surveys, precision photometry, and repeated monitoring over approximately 10' $\times$ 10' to 30' $\times$ 30'. Spectroscopic modes with $R \sim 1000$ and higher-resolution options approaching $R \sim 5000$ are being considered for galaxy surveys, transient classification, compact-object spectroscopy, and targeted studies. A dedicated coronagraph is also being studied for direct observations of nearby exoplanetary systems, with a current raw-contrast goal of order $10^{-8}$ and further gains expected from calibration and post-processing. Candidate mission configurations include the Sun–Earth L2 region and alternative Earth orbits, with the final choice driven by science performance, thermal stability, communications, operations, and mission cost. This paper defines the current science requirements, baseline technical configuration, and engineering trade space for further development of the 3.5mST concept.
Read the full abstract

All authors Yong-Woo Kang, Sang Hyun Lee, Juhan Kim, Jeong-Yeol Han, Sungwook E. Hong, Bongkon Moon, Donguk Song, Juhyung Kang, Myeong-Gu Park, Sang Chul Kim, Chung-Uk Lee, Sangmo Tony Sohn, Arman Shafieloo, David Parkinson, Hong Soo Park, Dohyeong Kim, Chan Park, Jungjoo Sohn, Young-Beom Jeon, Jong-Hak Woo, Hyung Mok Lee, Hong Bae Ann, Myungkook James Jee, Mansoo Choi, Changbom Park

Quantum Physics

Thouless pumping and generation of squeezed Fock-state superpositions in a Fock-state lattice

Ruo Kun Cai, Ling Lin, Chun Wang Wu et al. (+2 more)

In this paper, Thouless pumping in a one-dimensional semi-infinite Fock-state lattice is investigated. A distinctive feature of such lattices is the intrinsic $\sqrt{n}$-dependent coupling arising from the bosonic mode, which leads to spatially nonuniform hopping amplitudes. In the dimer limit, the topological invariants and the quantized transport dynamics in the Fock-state basis are numerically evaluated and analyzed. By introducing an additional inter-cell coupling and applying a squeezing transformation, the framework is then extended to Thouless pumping in the squeezed Fock-state basis, where a topologically protected scheme for preparing superpositions of squeezed Fock states is proposed. This study establishes Thouless pumping in Fock-state lattices as a useful tool for quantum state engineering, shifting the focus from observing topological transport to harnessing it for the preparation of non-classical states of the bosonic mode.
Read the full abstract

All authors Ruo Kun Cai, Ling Lin, Chun Wang Wu, Zhi Jiao Deng, Ping Xing Chen

Mesoscale and Nanoscale Physics

Direct Observation of the Zigzag Edge States of a Supramolecular Diatomic Kagome Lattice

Ryohei Nemoto, Xiangzhi Meng, Behzad Mortezapour et al. (+11 more)

Lattice geometry plays a fundamental role in the behavior of Bloch electrons in a crystal. The diatomic Kagome lattice, an extension of the honeycomb and Kagome lattices, is predicted to give rise to emergent and topological phenomena, but its experimental investigation has been limited thus far. Here, we fabricate a diatomic Kagome lattice through self-assembly of a triptycene derivative with phenazine moieties (Trip-Phz)—a $\mathrm{C_3}$-symmetric, non-planar $\pi$-conjugated molecule. Our scanning tunneling microscopy (STM) observations show that Trip-Phz forms a highly ordered diatomic Kagome lattice terminated by zigzag-type edges on the Pb(111) surface. Combined STM measurements and tight-binding calculations provide direct evidence for the existence of the edge states that correspond to those of graphene. These states are topological edge states dictated by the quantization of the Zak phase and the bulk-edge correspondence.This work reveals an ideal platform for exploring quantum materials with unique lattice geometries using supramolecular technology.
Read the full abstract

All authors Ryohei Nemoto, Xiangzhi Meng, Behzad Mortezapour, Alexander Weismann, Saya Nakano, Masahisa Tsuchiizu, Ryuichi Arafune, Noriaki Takagi, Sho Nakamura, Katsunori Wakabayashi, Rie Suizu, Richard Berndt, Takashi Uchihashi, Kunio Awaga

Earth and Planetary Astrophysics

Photometric characterization of near-Earth asteroids: rotation, taxonomy, and candidate evidence for internal cohesion

A. Carbognani, A. Buzzoni, M. Barbetta et al. (+1 more)

We present the results of a survey of previously uncharacterized near-Earth asteroids (NEAs) conducted between the second half of 2024 and the first months of 2026 using broadband $BVR_{c} I_{c}$ photometry and time-resolved lightcurve observations. Color indices were obtained for 14 NEAs of the 15 observed, with a dimension range between 0.11 and 2.5 km, and used to derive taxonomic classifications through comparison of a sample of reference reflectance curves. The sample appears to be dominated by S-, X-, and C-complex and V-type asteroids; absolute magnitudes and effective diameters were estimated using taxonomically appropriate albedos. Rotation periods were determined or constrained for several targets. Some large objects appear to rotate faster than the classical cohesionless spin barrier at $P\simeq 2.2$~h, although in some cases the period determinations remain tentative due to limited temporal coverage. A cohesive rubble-pile model provides a plausible explanation for the observed rapid rotation within the uncertainties of the derived physical parameters, and modest cohesive strengths of order $10^{2}$–$10^{4}$~Pa are sufficient to account for the observed rotation rates.
Read the full abstract

All authors A. Carbognani, A. Buzzoni, M. Barbetta, R. Gualandi

Quantum Physics

Combinatorial optimization of connected UAV communication bridges for emergency response

Matteo Vandelli and Daniele Dragoni

We present a combinatorial optimization problem for the strategic deployment of UAVs equipped with 5G antennas to assist rescue operations in regions hit by natural disasters. Our goal is to optimize the placement of UAVs to provide coverage in flying ad-hoc networks among given candidate sites. Our formulation aims to maximize signal coverage and minimize interference while ensuring network connectivity. To mitigate interference effects, we incorporate the use of multiple frequencies. We formulate this problem as an integer quadratic program (IQP). We present numerical solutions obtained via the CPLEX solver and conduct a preliminary analysis of the problem's scalability in realistic network configurations. Our findings reveal a significant exponential increase in Time-to-Solution (TTS) as the number of sites grows, which poses a critical challenge in urgent, time-sensitive scenarios. To address this issue, approximate suboptimal solutions can be produced by enforcing a time limit on the solver. Although these solutions are not optimal, they preserve connectivity in most cases, providing a practical trade-off between solution quality and computational times that remain within feasible limits for real-time UAV redeployment. Recognizing the limitations of classical solvers in these contexts, we explore quantum computing as a promising alternative. Specifically, we reformulate the problem as a quadratic unconstrained binary optimization (QUBO) problem, suitable for most quantum algorithms. Through high-performance computing emulation, we show that the quantum adiabatic algorithm (QAA) can accurately solve small-scale instances, paving the way for future application of quantum computing to large-scale, time-critical optimization problems in disaster response.
Read the full abstract

Quantum Physics

Optimal Fusion Strategies for Quantum Computation

Kenneth Goodenough, Andrew Landahl, Joon Lee et al. (+2 more)

Logical fusions are important for a number of tasks in quantum information, such as quantum error correction and quantum repeaters. In the photonic setting one must contend with the fact that physical fusions can fail, i.e. individual qubits are measured in a user-controlled product state basis with some probability, which can lead to a failure on the logical level. The choice of failure basis of each qubit is known as a fusion strategy, and finding good fusion strategies is important for optimizing performance of fusion-based quantum computation. Here we provide a complete characterization when $k=1$ qubits are encoded, and in particular characterize those codes and fusion strategies such that all but one physical fusion can fail, i.e.~perfect fusion strategies. In doing so, we recover previously known perfect fusion strategies, and find perfect fusion strategies for quantum parity-check codes, answering an open question. We furthermore show that perfect fusion strategies are generic: random $[[n, 1, d]]$ graph codes admit a perfect fusion strategy with probability exponentially close to $1$. Additionally we motivate the study of a new graph parameter, namely the maximum degree of a graph at a given vertex taken over all LC-equivalent graphs, by giving a new operationally meaningful interpretation of it.
Read the full abstract

All authors Kenneth Goodenough, Andrew Landahl, Joon Lee, Antonio Russo, Kevin Thompson

Astrophysics of Galaxies

Constraining reionization-era Ly$\alpha$ escape with JELS-MUSE: a highly complete H$\alpha$-selected sample at $z\sim6.1$

A. L. Patrick, K. J. Duncan, Z. Li et al. (+16 more)

The Ly$\alpha$ escape fraction, $f_{\rm{esc}}^{\rm{Ly}\alpha}$, probes both the interstellar medium (ISM) conditions governing ionizing photon escape and the rising neutral fraction of the IGM through the Epoch of Reionization (EoR). Characterising the intrinsic, ISM-driven distribution of $f_{\rm{esc}}^{\rm{Ly}\alpha}$ before IGM attenuation becomes dominant is essential to interpret the observed decline in Ly$\alpha$ visibility through the EoR. We present $f_{\rm{esc}}^{\rm{Ly}\alpha}$ measurements for a highly complete, H$\alpha$-flux-limited sample of 24 star-forming galaxies at $z \approx 6.1$, drawn from the JWST Emission Line Survey (JELS) and observed in Ly$\alpha$ with VLT/MUSE as part of the JELS-MUSE Large Area Survey. We detect Ly$\alpha$ in 12 of 24 sources and a Ly$\alpha$ emitter fraction of $X_{\rm{Ly}\alpha} = 33 \pm 12$ per cent using the canonical EW(Ly$\alpha$) $> 25 \, \mathring{\rm{A}}$ definition. Incorporating non-detections via reverse Kaplan-Meier survival analysis yields $\langle f_{\rm{esc}}^{\rm{Ly}\alpha} \rangle = 0.07^{+0.04}_{-0.03}$, consistent with an independent stacked-flux estimate of $0.08^{+0.02}_{-0.02}$. Using reionization simulations matched to the area, depth, and redshift range of our survey, we find that all galaxies are expected to experience broadly similar IGM transmission, so we postulate that the large scatter in $f_{\rm{esc}}^{\rm{Ly}\alpha}$ reflects genuine ISM-driven variance rather than differences in the surrounding IGM. Among the detections, higher $f_{\rm{esc}}^{\rm{Ly}\alpha}$ galaxies tend to have lower nebular dust attenuation, bluer UV slopes, and lower stellar mass, consistent with feedback-regulated escape through localised, low-column-density ISM channels around star-forming regions. These results benchmark intrinsic Ly$\alpha$ escape at the end of reionization, against which IGM suppression at $z > 7$ can be interpreted.
Read the full abstract

All authors A. L. Patrick, K. J. Duncan, Z. Li, C. A. Pirie, A. M. Swinbank, L. C. Keating, S. R. Flury, R. Begley, P. N. Best, M. Brinch, A. C. Carnall, F. Cullen, J. S. Dunlop, E. Ibar, J. Matthee, D. J. McLeod, A. Puglisi, H. M. O. Stephenson, J. P. Stott

Solar and Stellar Astrophysics

Solar Soft X-ray Coronal Dimming in a Failed Eruption Associated with Plasma Cooling

Xinyue Wang, Astrid M. Veronig, Hechao Chen et al. (+1 more)

Coronal dimmings are observed as sudden and localized reductions in the extreme-ultraviolet and X-ray emission of the solar corona. Traditionally, significant dimmings of spectral lines formed at temperatures of 1-2 MK are regarded as indicators of coronal mass ejections (CMEs), reflecting the density depletion caused by plasma escaping into interplanetary space. In this Letter, we report a peculiar deep coronal dimming event predominantly observed in high-temperature spectral lines following an M8.8-class confined solar flare associated with a failed filament eruption. Sun-as-a-star measurements from the Geostationary Operational Environmental Satellite and the Extreme Ultraviolet Variability Experiment reveal intensity reductions exceeding 30% in soft X-ray (SXR) and measurable decreases in Fe XVIII (6.5 MK) and Fe XX (9.3 MK). Spatially resolved observations from the Atmospheric Imaging Assembly demonstrate that the dimming originates from the active region core, while the Solar Terrestrial Relations Observatory-A shows no evidence for CME-driven mass loss. Differential emission measure analysis reveals plasma at temperatures >5 MK cooling into lower temperatures, supporting plasma cooling as the dominant contributor to the hot-band dimming rather than CME-associated plasma escape. This event demonstrates that deep hot SXR dimmings can occur without substantial CME-driven mass loss, suggesting that alternative physical mechanisms may also account for unresolved stellar dimmings in addition to the commonly inferred CME signatures.
Read the full abstract

All authors Xinyue Wang, Astrid M. Veronig, Hechao Chen, Hui Tian

Quantum Physics

Experimental Evaluation of Passive Polarization Compensation Techniques for Fiber-Distributed Polarization-Entangled Photons

Gayatri Thik, Amit Loyal, Srinivasan K et al. (+1 more)

Entanglement distribution through optical fibers is essential for quantum communication networks; however, fiber transmission can alter photon polarization and modify the observed correlations of polarization-entangled states, necessitating polarization compensation to recover the desired entangled state in the measurement basis. Here, we experimentally evaluate two passive polarization compensation techniques: a free-space Quarter-Half-Quarter (QHQ) waveplate configuration and an in-fiber three-paddle Fiber Polarization Controller (FPC). The polarization transformation along each downconverted-photon path is independently compensated through a systematic path-by-path optimization procedure. Using both techniques, we recover high-quality polarization correlations and entanglement, with visibilities exceeding $93\%$ in three mutually unbiased bases and fidelities above $94.5\%$. The results demonstrate comparable restoration using free-space waveplate-based and fiber-based control, establishing a systematic framework for laboratory and short-reach quantum communication links.
Read the full abstract

All authors Gayatri Thik, Amit Loyal, Srinivasan K, Raghavan G

Optics

Comparative study of noise-like pulse emission from Mamyshev oscillator and conventional passively mode-locked fiber laser

Oumaima Ougrige, Florent Bessin and François Sanchez

We perform an in-depth comparison of noise-like pulse emission from Mamyshev oscillator and mode-locking through nonlinear polarization rotation (NPR) in fiber lasers. NLP's temporal and spectral characteristics are analyzed in both normal and anomalous dispersion regimes. The output coupling coefficient is modified to optimize the energy of the output pulses. It is demonstrated that the pulse energy is systematically higher in NPR-based mode-locking fiber lasers than in Mamyshev oscillators. This is due to the filtering effect in the Mamyshev oscillator which rejects ultrashort pulses whose energy is insufficient to successfully pass through the two shifted optical filters.
Read the full abstract

High Energy Astrophysical Phenomena

Are jet speeds governed by accretion modes?

Hong Tu, Xinwu Cao and Andrzej A. Zdziarski

Relativistic jets are observed in both stellar-mass black hole X-ray binaries (BHXRBs) and active galactic nuclei (AGNs), yet their bulk Lorentz factors differ systematically—those in black hole X-ray binaries are typically below $\sim2$, whereas AGN jets can reach $\sim50$. The origin of this discrepancy remains unclear. Searching the literature, we compile a sample of 333 AGNs with well-measured jet component motions, consisting of 270 quasars, 47 BL Lac objects, 10 FRI, and 6 FRII galaxies. We find that quasars/FRIIs exhibit minimal bulk Lorentz factors ranging from $\sim$1.0 to 41.5, with a mean of 11.5 (median 9.5). In contrast, BL Lac objects/FRIs show $\Gamma_{\rm jet}\sim$1.0–21.9, averaging 4.2 (median 1.5). These values, particularly the median, closely resemble those of BHXRBs, implying a strong correlation between jet speed and accretion mode. The Lorentz factor of a magnetically driven jet is mainly determined by the ratio of the magnetic pressure to rest mass energy density at the jet base. In BL Lacs/FRIs/BHXRBs, the field is maintained by the advection-dominated accretion flow (ADAF), and the gas at the ADAF surface is magnetically driven into the jets. In quasars/FRIIs, the field is maintained by the disc, while the jet base is connected to the corona. Our model calculations show that the disc field is always much stronger than that of the ADAF, and therefore leads to a larger $\Gamma_{\rm jet}$, which can explain the systematic difference in $\Gamma_{\rm jet}$ between these two types of sources.
Read the full abstract

Solar and Stellar Astrophysics

Visual Discovery of Fading Events in the Wolf-Rayet Star WR 80

Rod Stubbings

Long-term visual and CCD V-band monitoring of the heavily reddened Wolf-Rayet star WR 80 from 2017-2026 reveals optical fading events that depart from its long-term stable baseline. On 26 April 2017 (JD 2457870), I discovered a deep minimum using a 22-inch (0.56-m) telescope, with the source plunging from a baseline of magnitude 14.6 down to magnitude 15.8. This 6-day event was subsequently verified via archival ASAS-SN V-band records. In July 2018, my visual observations identified a short duration fade to magnitude 15.4 that went undetected in concurrent electronic V band data streams, indicating a masking effect likely caused by near-infrared red leak contamination in the CCD filters. Following a stable phase recorded by continuous CCD V-band tracking from 2023 through early 2026, a mid-2026 visual detection caught a full 16-day fading event reaching a minimum magnitude of 15.3. These combined datasets establish that WR 80 undergoes highly variable optical obscuration events.
Read the full abstract

Atmospheric and Oceanic Physics

Did recent sea surface temperature warming reinforce the extreme East Asian summer monsoon precipitation in 2020?

Taeho Mun, Haerin Park, Dong-Hyun Cha et al. (+3 more)

We analyzed the possible effects of recent sea surface temperature (SST) warming on the extraordinary East Asian summer monsoon (EASM) precipitation in 2020 summer. The dynamic and thermodynamic impacts of SST are examined by conducting regional climate model experiments with observed SST and cold SST where the 22-year SST trend is removed. In the presence of warm SST, precipitation increases in low latitudes but decreases in the EASM region. This dipolar precipitation change pattern opposes the precipitation anomalies in 2020 summer, indicating that the extraordinary 2020 EASM precipitation is not likely driven by recent SST warming. The warm SST suppresses the western North Pacific subtropical high expansion and weakens the southwesterly from the South China Sea toward the EASM region. In terms of large-scale atmospheric circulations, SST-induced wind changes strengthen the local Walker circulation in the South China Sea and the Philippines and the local Hadley circulation across the EASM region. These support the reduced EASM rainfall in the control experiment compared to the cold SST experiment and imply that the precipitation reduction by dynamical effects could exceed the precipitation increase by thermodynamic effects in the EASM region under warm SST.
Read the full abstract

All authors Taeho Mun, Haerin Park, Dong-Hyun Cha, Chang-Keun Song, Seung-Ki Min, Seok-Woo Son

Mathematical Physics

Bimaterial Eshelby's inclusion problem for polyhedra

Chunlin Wu and Huiming Yin

This paper presents the closed-form Eshelby's tensor for an arbitrarily oriented polyhedral inclusion in a bimaterial domain under general uniform eigenstrain. Existing bimaterial solutions are mainly restricted to special inclusion shapes or dilatational eigenstrains, because the bimaterial Green's function contains two Boussinesq's displacement potentials in addition to the harmonic and biharmonic potentials in Kelvin's solution. This paper derives the missing domain integrals of the two Boussinesq's potentials by reducing the volume integrals to surface and elementary line integrals. The formulae provide the complete elastic and thermoelastic bimaterial Eshelby's tensors, which are verified against analytical solutions for spherical and cuboidal inclusions parallel to the bimaterial interface, and finite element results of an inclined cuboid. Singularity analysis demonstrates that the interface-related contribution remains regular when the inclusion is separated from the bimaterial interface, while additional logarithmic singularities arise when an edge or vertex touches the interface without increasing the dominant singularity order.
Read the full abstract