物理与天体物理最新文献

{"title":"Ultrasonic imaging of spherical solids embedded in ice.","authors":"Francesco Simonetti","doi":"10.1016/j.ultras.2025.107779","DOIUrl":"10.1016/j.ultras.2025.107779","url":null,"abstract":"<p><p>The transmission of compressional ultrasonic waves into a rigid and dense solid with a doubly-curved surface is impeded when the solid is placed in a liquid medium and its surface is irradiated with waves traveling through the liquid. Measurable power transmission is only possible when the incident ultrasonic beam is close to normal to the surface. This condition is difficult to realize when the waves are excited and detected by a linear array of transducers and limits the possibility of forming cross-sectional images of the solid from the array data. Here, it is shown that the interior of the solid can be imaged with enhanced fidelity if the water is frozen. The high speed of compressional waves in polycrystalline ice (approximately 4000 ms^-1) along with its rigid behavior ensure that ultrasonic waves can be transmitted through the surface over a broad range of angles of incidence. However, due to the double curvature, the rays that form the ultrasonic beam can be deflected outside the array azimuthal plane after entering the solid. Therefore, the two-dimensional images obtained from the linear array data may not be consistent with the fully three-dimensional structure of the ray paths. The analysis of this phenomenon for the special case of solid spheres reveals that the image, to a good approximation, corresponds to a section of the sphere that is parallel to the azimuthal plane and at a standoff distance from it. The distance increases with the angle that the normal to the surface forms relative to the azimuthal plane while it decreases as the velocity contrast between ice and the material of the sphere decreases. While this property is not expected to hold for more complex surfaces, the ray-based framework used in this study is applicable to more general surface configurations and can be used to correlate the images to the structure of the solid. These findings are relevant to the inspection of metallic components with complex geometry which represents a long-standing challenge in the field of nondestructive testing.</p>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"157 ","pages":"107779"},"PeriodicalIF":4.1,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144822733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic algorithm-enabled quantitative characterization of planar defect using local resonance frequency and attenuation.","authors":"Shuang Xu, Kai Wang, Honglin Yan, Wenxin Lai, Paixin Chen, Weibin Li, Ruiqi Guan, Hua Zhang, Kaixiang Gong","doi":"10.1016/j.ultras.2025.107780","DOIUrl":"10.1016/j.ultras.2025.107780","url":null,"abstract":"<p><p>Driven by the applications of advanced manufacturing technologies which enable complex designs, the nondestructive evaluation of damage in complex structures is playing an increasingly important role across various industries. The local defect resonance (LDR) has demonstrated greater applicability to defects in complex thin-walled structures than traditional methods. However, existing LDR-based methods suffer from the low accuracy in the quantitative evaluation of defect owing to the difficulty in determining the defect boundary. A method based on the frequency and attenuation of LDR is proposed in this investigation to quantify the diameter and thickness of circular defects simultaneously using the genetic algorithm. In this method, the reflections of guided ultrasonic waves at defect boundaries are analyzed using a normal mode expansion method, and thereby the relations between the FBH parameters (i.e., diameter and thickness) and LDR attributes (i.e., the frequency and attenuation rate) are obtained. On this basis, a method based on a genetic algorithm is proposed to inversely determine the defect parameters using the LDR attributes. The proposed method is validated through numerical investigation and experimental evaluations of a series of flat bottom holes in plate structures. The proposed method enhances the accuracy and efficiency for the quantitative evaluation of defects in complex structures, advancing the application of LDR-based nondestructive evaluation techniques and providing basis for developing structural health monitoring techniques using LDR.</p>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"157 ","pages":"107780"},"PeriodicalIF":4.1,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144817593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Precise acoustic field establishment by holography-modulated acoustic intensity.","authors":"Hao Quan, Wei Zhou, Xinjia Li, Pengqi Li, Xiufang Liu, Fei Li, Lili Niu, Long Meng","doi":"10.1016/j.ultras.2025.107781","DOIUrl":"10.1016/j.ultras.2025.107781","url":null,"abstract":"<p><p>Acoustic holography, which reconstructs desired target acoustic fields by precisely controlling the phase distribution of acoustic wavefronts, holds significant promise for applications such as acoustic manipulation. However, the precise modulation of acoustic field distributions via acoustic holography to construct multifocal fields with controllable acoustic intensity ratios remains insufficiently explored. To address this limitation, this study proposes a Physics-Informed Artificial Intelligence-based Angular Spectrum method (AIAS), which deeply integrates the physical model of angular spectrum propagation into the neural network training process. Combined with a specifically designed Target-Area-Weighted Mean Squared Error loss function, AIAS establishes an explicit optimization link between the phase distribution and the amplitude error in the target region during the inverse design process. Results demonstrate that acoustic fields reconstructed by AIAS exhibit more concentrated and uniform pressure distributions (average pressure improved from 262 ± 15 kPa to 276.4 ± 5.6 kPa), providing stable acoustic fields for particle assembly. Importantly, by controlling the phase gradient distribution, AIAS successfully constructs asymmetric acoustic fields with a 2:1 intensity ratio between two focal points. The exceptional amplitude modulation capabilities of AIAS represent a key technological breakthrough for achieving more precise and personalized transcranial focused ultrasound therapy.</p>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"157 ","pages":"107781"},"PeriodicalIF":4.1,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144812477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Noncontact pulsed laser-scanning laser Doppler vibrometer (PL-SLDV) phased array imaging for damage detection in composites.","authors":"Bowen Cai, Luyu Bo, Andrew Campbell, Jiali Li, Chongpeng Qiu, Hongye Liu, Lingyu Yu, Zhenhua Tian","doi":"10.1016/j.ultras.2025.107787","DOIUrl":"10.1016/j.ultras.2025.107787","url":null,"abstract":"<p><p>Guided wave phased arrays, which use multiple sensors in compact patterns to perform damage imaging through phase delays, have garnered significant interest for the rapid inspection of large composite panels. Previous phased arrays typically used large, wired ultrasonic transducers attached to composites, limiting array reconfigurability and preventing contactless inspection from a distance. This study presents a fully noncontact guided wave phased array imaging approach, which utilizes a dual laser-based guided wave generation and sensing system, namely a pulsed laser-scanning laser Doppler vibrometer (PL-SLDV) system, along with synthetic phased array beamforming and wavefield analysis. The PL-SLDV system employs a Q-switched PL module to generate nanosecond laser pulses that excite ultrasonic guided waves through the thermoelastic effect. To ensure consistent laser-to-ultrasound energy conversion across different composites and prevent potential thermal damage to composites, the laser pulses are directed onto a thin aluminum patch bonded on the composite. The SLDV acquires guided wave signals based on the Doppler effect, and its integrated galvo mirrors can quickly steer laser beam directions to scan a composite plate, thereby acquiring guided wave signals at various array points. Time/phase delays are then applied to the acquired signals through post-processing for synthetic phased array beamforming. To generate inspection images using the acquired wave signals, an improved delay-and-sum (DAS) imaging algorithm is introduced. It uses adaptive weighting factors and incorporates phase delay and back-propagation phase shift, accounting for the frequency- and direction-dependent dispersion relation, to overcome the dispersion effect and directional dependency of waves in anisotropic materials. Moreover, the fusion of phased array imaging and a wavefield analysis approach, which can extract frequency-wavenumber dispersion relations from experimental wavefields, enables our phased array method to perform damage imaging without requiring prior knowledge of composite properties, such as mechanical properties or theoretical dispersion curves. Additionally, the noncontact wave generation/acquisition feature of our PL-SLDV system allows for inspecting composites from a distance and easily constructing phased arrays with different patterns. Proof-of-concept experiments demonstrate that multiple defects in different directions can be successfully detected. Additionally, this study reveals that PL-generated guided waves can contain multiple modes, such as A₀, S₀, SH₀, A₁, S₁, and SH₁ modes, offering valuable insights for researchers interested in using PL-generated guided waves.</p>","PeriodicalId":23522,"journal":{"name":"Ultrasonics","volume":"157 ","pages":"107787"},"PeriodicalIF":4.1,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144817594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Qualitative Study of How Hospice Workers Cope With Their Level of Exposure to Death.","authors":"Alex Sielaff, Lyla Rothschild, Dylan E Horner, Jeff Greenberg","doi":"10.1177/00302228231184297","DOIUrl":"10.1177/00302228231184297","url":null,"abstract":"<p><p>ObjectiveTo identify whether hospice workers hold unique and theoretically-informative perspectives about death, especially as they relate to terror management processes.MethodTwelve hospice workers from two hospices in Tucson, Arizona, United States, participated in semi-structured interviews. Interview and analytic practices were guided by Grounded Theory (Glaser & Strauss, 1967).ResultsThree categories were identified in relation to death attitudes: effects of chronic confrontation with death; reasons for working in hospice; and perceptions of death in others.ConclusionsTwo theoretically informative trends appeared. First, hospice workers largely manage death anxiety as identified by existing literature with the notable exception that hospice workers overall seem to integrate death and dying into their worldviews as a meaningful category, as opposed to avoiding thinking about death. Second, even among those regularly exposed to death, there seems to be a range across participants on a continuum from avoiding to confronting the topic of death.</p>","PeriodicalId":48702,"journal":{"name":"Physical Review a","volume":"80 1","pages":"356-377"},"PeriodicalIF":2.9,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84245119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NNLO QCD calculation of hadron multiplicities in light-quark jets at lepton colliders","authors":"Bin Zhou, Jun Gao","doi":"10.1103/tjy3-tdxv","DOIUrl":"https://doi.org/10.1103/tjy3-tdxv","url":null,"abstract":"We present the calculation of next-to-next-to-leading-order (NNLO) QCD corrections to hadron multiplicities in light-quark jets at lepton colliders, employing the “projection-to-Born” (P2B) method implemented in the FMNLO program. Taking the next-to-leading-order result as an example, we rigorously establish the validity of our P2B-based calculation. We then present NNLO predictions for the normalized asymmetry D</a:mi>K</a:mi>−</a:mo></a:msup></a:msub></a:math> between hadron and antihadron production in light-quark jets and compare them with SLD data. We find that a suppression of these SLD measurements relative to NPC23 predictions for <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><c:msub><c:mi>D</c:mi><c:msup><c:mi>K</c:mi><c:mo>−</c:mo></c:msup></c:msub></c:math> emerges in the intermediate <e:math xmlns:e=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><e:msub><e:mi>z</e:mi><e:mi>h</e:mi></e:msub></e:math> domain (<g:math xmlns:g=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><g:mn>0.2</g:mn><g:mo>≲</g:mo><g:msub><g:mi>z</g:mi><g:mi>h</g:mi></g:msub><g:mo>≲</g:mo><g:mn>0.7</g:mn></g:math>). We expect that incorporating these SLD data into global QCD fits will enable improved determination of fragmentation functions.","PeriodicalId":20167,"journal":{"name":"Physical Review D","volume":"9 1","pages":""},"PeriodicalIF":5.0,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145288743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reinterpretation of chiral anomaly on a lattice","authors":"Huan-Wen Wang, Bo Fu, Shun-Qing Shen","doi":"10.1103/g65h-sz4b","DOIUrl":"https://doi.org/10.1103/g65h-sz4b","url":null,"abstract":"","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":"45 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145288845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Postsphaleron darkogenesis","authors":"Sudhakantha Girmohanta, Yuichiro Nakai, Zhihao Zhang","doi":"10.1103/jyg8-y433","DOIUrl":"https://doi.org/10.1103/jyg8-y433","url":null,"abstract":"A supercooled phase transition in a nearly conformal dark sector can provide a natural setting for darkogenesis via its out-of-equilibrium dynamics, where a particle-antiparticle number asymmetry in the dark sector can be reprocessed into the visible sector, yielding the observed baryon asymmetry and an asymmetric dark matter. We consider a scenario where the number asymmetry is generated from the decay of a mother particle produced via parametric resonance during the phase transition induced due to its coupling to the dilaton associated with spontaneous breaking of scale invariance. It is shown that the correct baryon asymmetry and dark matter abundance can be realized for a dark phase transition at O</a:mi>(</a:mo>1</a:mn>)</a:mo></a:mtext></a:mtext>GeV</a:mi></a:mrow></a:math>, which can also explain the nanohertz gravitational wave signal reported by pulsar timing array experiments. The scenario will be tested further in neutron-antineutron oscillation experiments.","PeriodicalId":20167,"journal":{"name":"Physical Review D","volume":"85 1","pages":""},"PeriodicalIF":5.0,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145288744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-dimensional topological orbital Hall effect caused by magnetic hopfions","authors":"Börge Göbel, Samir Lounis","doi":"10.1103/sc9g-l9by","DOIUrl":"https://doi.org/10.1103/sc9g-l9by","url":null,"abstract":"Magnetic hopfions are noncollinear spin textures that are characterized by an integer topological invariant, called the Hopf index. The three-dimensional magnetic solitons can be thought of as a tube with a twisted magnetization that has been closed at both ends to form a torus. The tube consists of a magnetic whirl called an in-plane skyrmion or bimeron. Although hopfions have been observed by microscopy techniques, their detection remains challenging as they lack an electronic hallmark so far. Here we predict a three-dimensional orbital Hall effect caused by hopfion textures: When an electric field is applied, the hopfion generates a transverse current of orbital angular momentum. The effect arises due to the local emergent field that gives rise to in-plane and out-of-plane orbital Hall conductivities. This orbital Hall response can be seen as a hallmark of hopfions and allows us to distinguish them from other textures, such as skyrmioniums, that look similar in real-space microscopy experiments. While the two-dimensional topological invariant of a skyrmion determines its topological Hall transport, the unique three-dimensional topological orbital Hall effect can be identified with the three-dimensional topological invariant that is the Hopf index. Our results make hopfions attractive for spin-orbitronic applications because their orbital signatures allow for their detection in devices and give rise to large orbital torques.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":"67 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145288844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Femtosecond and Attosecond Phase-Space Correlations in Few-Particle Photoelectron Pulses","authors":"Rudolf Haindl, Valerio Di Giulio, Armin Feist, Claus Ropers","doi":"10.1103/lylq-m63c","DOIUrl":"https://doi.org/10.1103/lylq-m63c","url":null,"abstract":"Temporal correlations in pulsed electron beams reflect the microscopic dynamics of emission and interparticle interaction. In femtosecond electron emission from nanoscale field emitters, Coulomb interactions result in structured few-electron states with strong correlations in energy, time, and transverse momentum. Interactions with external fields may be used to both probe and further manipulate these correlated states. Here, we combine femtosecond-gated, event-based detection with inelastic electron-light scattering to directly map the photoelectron phase-space distribution of two-electron states. Our experiments demonstrate a bimodal structure in longitudinal phase space, with distinct contributions from interparticle interaction and dispersion. Moreover, we imprint a global phase modulation onto two-electron states and theoretically show that coherent shaping of few-electron phase-space distributions enables attosecond temporal correlations. This controlled phasing of few-electron states can be harnessed to produce tailored excitations and superradiance via two-electron energy postselection.","PeriodicalId":20069,"journal":{"name":"Physical review letters","volume":"13 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145288975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}