bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photon ring test of the Kerr hypothesis: Variation in the ring shape
Authors: Paugnat H. , Lupsasca A. , Vincent F. H. , Wielgus M. 
Published: September 2022

Context. The Event Horizon Telescope (EHT) collaboration recently released horizon-scale images of the supermassive black hole M87*. These images are consistently described by an optically thin, lensed accretion flow in the Kerr spacetime. General relativity (GR) predicts that higher-resolution images of such a flow would present thin, ring-shaped features produced by photons on extremely bent orbits. Recent theoretical work suggests that these “photon rings” produce clear interferometric signatures that depend very little on the astrophysical configuration and whose observation could therefore provide a stringent consistency test of the Kerr hypothesis.
Aims. We wish to understand how the photon rings of a Kerr black hole vary with its surrounding emission. Gralla, Lupsasca, and Marrone (GLM) found that the shape of high-order photon rings follows a specific functional form that is insensitive to the details of the astrophysical source, and proposed a method for measuring this GR-predicted shape via space-based interferometry. We wish to assess the robustness of this prediction by checking it for a variety of astrophysical profiles, black hole spins, and observer inclinations.
Methods. We use the ray tracing code Gyoto to simulate images of thin equatorial disks accreting onto a Kerr black hole. We extract the shape of the resulting photon rings from their interferometric signatures using a refinement of the method developed by GLM. We repeat this analysis for hundreds of models with different emission profiles, black hole spins, and observer inclinations.
Results. We identify the width of the photon ring and its angular variation as a main obstacle to the method’s success. We qualitatively describe how this width varies with the emission profile, black hole spin, and observer inclination. At low inclinations, our improved method is robust enough to confirm the shape prediction for a variety of emission profiles; however, the choice of baseline is critical to the method’s success. At high inclinations, we encounter qualitatively new effects that are caused by the ring’s non-uniform width and require further refinements to the method. We also explore how the photon ring shape could constrain black hole spin and inclination.
Fossil group origins
Authors: Zarattini S. , Aguerri J. A. L. , Calvi R. , Girardi M. 
Published: September 2022

Aims. We analyse the large-scale structure out to 100 Mpc around a sample of 16 confirmed fossil systems using spectroscopic information from the Sloan Digital Sky Survey Data Release 16.
Methods. We computed the distance between our fossil groups (FGs) and the centres of filaments and nodes from the literature. We also studied the density of bright galaxies, since this parameter is thought to be a good mass tracers, as well as the projected over-densities of galaxies. Finally, we applied a friends-of-friends (FoF) algorithm to detect virialised structures around our FGs and obtain an estimate of the mass available in their surroundings.
Results. We find that FGs are mainly located close to filaments, with a mean distance of 3.7 ± 1.1 R200 and a minimum distance of 0.05 R200. On the other hand, none of our FGs were found close to intersections, with a mean and minimum distance of 19.3 ± 3.6 and 6.1 R200, respectively. There is a correlation that indicates FGs at higher redshifts are found in denser regions, when we use bright galaxies as tracers of the mass. At the same time, FGs with the largest magnitude gaps (Δm12 >  2.5) are found in less dense environments and tend to host (on average) smaller central galaxies.
Conclusions. Our results suggest that FGs formed in a peculiar position within the cosmic web, close to filaments and far from nodes, whereby their interaction with the cosmic web itself may be limited. We deduce that FGs with brightest central galaxies (BCGs) that are relatively faint, high values of Δm12, and low redshifts could, in fact, be systems that are at the very last stage of their evolution. Moreover, we confirm theoretical predictions that systems with the largest magnitude gap are not massive.
FilDReaMS
Authors: Carrière J.-S. , Ferrière K. , Ristorcelli I. , Montier L. 
Published: September 2022

Context.Both simulations and observations of the interstellar medium show that the study of the relative orientations between filamentary structures and the magnetic field can bring new insight into the role played by magnetic fields in the formation and evolution of filaments and in the process of star formation.Aims.We provide a first application ofFilDReaMS, the new method presented in the companion paper to detect and analyze filaments in a given image. The method relies on a template that has the shape of a rectangular bar with variable width. Our goal is to investigate the relative orientations between the detected filaments and the magnetic field.Methods.We applyFilDReaMSto a small sample of fourHerschelfields (G210, G300, G82, G202) characterized by different Galactic environments and different evolutionary stages. First, we look for the most prevalent bar widths, and we examine the networks formed by filaments of different bar widths as well as their hierarchical organization. Second, we compare the filament orientations to the magnetic field orientation inferred fromPlanckpolarization data and, for the first time, we study the statistics of the relative orientation angle as functions of both spatial scale and H2column density.Results.We find preferential relative orientations in the fourHerschelfields: small filaments with low column densities tend to be slightly more parallel than perpendicular to the magnetic field; in contrast, large filaments, which all have higher column densities, are oriented nearly perpendicular (or, in the case of G202, more nearly parallel) to the magnetic field. In the two nearby fields (G210 and G300), we observe a transition from mostly parallel to mostly perpendicular relative orientations at an H2column density ≃ 1.1 × 1021cm−2and 1.4 × 1021cm−2, respectively, consistent with the results of previous studies.Conclusions.Our results confirm the existence of a coupling between magnetic fields at cloud scales and filaments at smaller scale. They also illustrate the potential of combiningHerschelandPlanckobservations, and they call for further statistical analyses with our dedicated method.
Cultural Sensitivity and Ethical Considerations
Authors: Bobel Matthew Cronon , Al Hinai Alreem , Roslani April Camilla 
Published: September 2022

AbstractGlobal surgery is a burgeoning area of global health. Surgeons can engage in one–or many–of the facets of global healthcare delivery: clinical care, capacity building, education, research, etc. Working in an increasingly global community, surgeons must be aware of the richness of cultural diversity at home and around the world such that they can provide culturally sensitive care. This chapter focuses on the most common way in which surgeons engage in global surgery: surgical short-term experiences in global health (STEGHs). Surgical STEGHs pose an intricate set of ethical dilemmas. As team leaders, surgeons must understand the community they intend to serve on these trips. Further, they should confirm that everyone who joins them is prepared to deliver care in a culturally sensitive and competent manner. Finally, surgeons must consider potential ethical dilemmas that may arise before, during, and after surgical STEGHs and have strategies to navigate them.
Noninvasive Brain Stimulation Therapies to Promote Recovery of Consciousness: Where We Are and Where We Should Go
Authors: Barra Alice , Monti Martin , Thibaut Aurore 
Published: September 2022

AbstractTherapeutic options for patients with disorders of consciousness (DoC) are still underexplored. Noninvasive brain stimulation (NIBS) techniques modulate neural activity of targeted brain areas and hold promise for the treatment of patients with DoC. In this review, we provide a summary of published research using NIBS as therapeutic intervention for DoC patients, with a focus on (but not limited to) randomized controlled trials (RCT). We aim to identify current challenges and knowledge gaps specific to NIBS research in DoC. Furthermore, we propose possible solutions and perspectives for this field. Thus far, the most studied technique remains transcranial electrical stimulation; however, its effect remains moderate. The identified key points that NIBS researchers should focus on in future studies are (1) the lack of large-scale RCTs; (2) the importance of identifying the endotypes of responders; and (3) the optimization of stimulation parameters to maximize the benefits of NIBS.
A high-Q superconducting toroidal medium frequency detection system with a capacitively adjustable frequency range &gt;180 kHz
Authors: Völksen F. , Devlin J. A. , Borchert M. J. , Erlewein S. R. , Fleck M. , Jäger J. I. , Latacz B. M. , Micke P. , Nuschke P. , Umbrazunas G. , Wursten E. J. , Abbass F. , Bohman M. A. , Popper D. , Wiesinger M. , Will C. , Blaum K. , Matsuda Y. , Mooser A. , Ospelkaus C. , Smorra C. , Soter A. , Quint W. , Walz J. , Yamazaki Y. , Ulmer S. 
Published: September 2022

We describe a newly developed polytetrafluoroethylene/copper capacitor driven by a cryogenic piezoelectric slip-stick stage and demonstrate with the chosen layout cryogenic capacitance tuning of ≈60 pF at ≈10 pF background capacitance. Connected to a highly sensitive superconducting toroidal LC circuit, we demonstrate tuning of the resonant frequency between 345 and 685 kHz, at quality factors Q &gt; 100 000. Connected to a cryogenic ultra low noise amplifier, a frequency tuning range between 520 and 710 kHz is reached, while quality factors Q &gt; 86 000 are achieved. This new device can be used as a versatile image current detector in high-precision Penning-trap experiments or as an LC-circuit-based haloscope detector to search for the conversion of axion-like dark matter to radio-frequency photons. This new development increases the sensitive detection bandwidth of our axion haloscope by a factor of ≈1000.
Exciton–exciton annihilation in thin indium selenide layers
Authors: Yang Zhangqiang , Zhang Jiaxiang , Ding Xingyu , Sheng Ziqian , Zhang Kelvin H. L. , Chen Lan , Yang Ye 
Published: September 2022

The photocarrier recombination in van der Waals layers may determine the device performance based on these materials. Here, we investigated the photocarrier dynamics in a multilayer indium selenide nanofilm using transient absorption spectroscopy. The sub-bandgap transient absorption feature was attributed to the indirect intraband absorption of the photocarriers, which was then exploited as a probe to monitor the photocarrier dynamics. With increasing pump intensities, the photocarrier decay was accelerated because of the rising contribution from a bimolecular recombination channel that was then assigned to exciton–exciton annihilation. The rate constant of the exciton–exciton annihilation was given as (1.8 ± 0.1) × 10−15 cm2 ps−1 from a global fitting of the photocarrier decay kinetics for different pump intensities. Our finding suggests that, in contrast with their monolayer counterpart, the exciton–exciton annihilation is rather inefficient in multilayers due to their weaker Coulomb interaction. Hence, compared with monolayers, the lifetime of photocarriers in multilayers would not be significantly reduced under high-intensity pump conditions, and the apparent photocarrier lifetime could be further improved just by suppressing the monomolecular recombination channels such as trapping.
Provision of other medical work by Australian early-career general practitioners: a cross-sectional study
Authors: Bentley Michael , FitzGerald Kristen , Fielding Alison , Moad Dominica , Tapley Amanda , Davey Andrew , Holliday Elizabeth , Ball Jean , Kirby Catherine , Turnock Allison , Spike Neil , van Driel Mieke , Magin Parker 
Published: September 2022

Introduction There is a trend towards GPs diversifying their role by working in health areas beyond general practice. However, little is known about whether this trend is apparent among early-career GPs once they make the transition from training to independent practice. Aim To describe the prevalence of and characteristics associated with early-career GPs providing other medical work. Methods A cross-sectional questionnaire-based study of GPs (‘alumni’) who had fellowed within the past 2 years from three of Australia’s nine regional training programs. The outcome factor was provision of medical work in addition to clinical general practice. Associations of independent variables (encompassing alumni demographics, current practice characteristics and vocational training experience) with the outcome were estimated using univariate and multivariable logistic regression. Results Of 339 responding alumni, 111 (33%) undertook other regular medical work. Sixty-five (59%) of these were in medical education. In multivariable analysis, factors associated with providing other medical work were having a spouse/partner not in the workforce (odds ratio (OR) 5.13), having done any training part-time (OR 2.67), providing two or more of home visits, nursing home visits and after-hours care (OR 2.20), working fewer sessions per week (OR 0.74), and currently working in an area of lower socio-economic status (OR 0.84). Having dependent children (OR 0.27), and being female (OR 0.43) were associated with not providing other medical work. Discussion In this study, many early-career GPs are providing other medical work, particularly medical education. Acknowledging this is important to general practice workforce planning and education policy.
Minority-carrier dynamics in β-gallium oxide probed by depth-resolved cathodoluminescence
Authors: Sugie Ryuichi , Uchida Tomoyuki 
Published: September 2022

Abstract
The behavior of hole polarons in β-gallium oxide (Ga2O3) has attracted significant attention. Depth-resolved cathodoluminescence (CL) was used to investigate the minority carrier dynamics in β-Ga2O3. First, a model describing CL intensity was proposed by considering the depth-dose function and surface recombination. A universal depth-dose function for β-Ga2O3, which has the form of a third-degree polynomial, was presented based on Monte Carlo simulation by introducing a normalized depth, which is the depth normalized by the electron beam range. Second, two experimental approaches, plan-view and cross-sectional CL measurements, were applied to unintentionally doped β-Ga2O3 (−201) wafers, and the experimental results were compared with those of the proposed model. The hole diffusion length was estimated to be within the range of 200–400 nm through the plan-view measurement, whereas a hole diffusion length of 250 nm was obtained through the cross-sectional measurement. The values were consistent with each other, and the model reproduced the experimental results well. This indicates that the nonequilibrium minority hole in the unintentionally doped β-Ga2O3 is mobile and forms a ‘weak’ polaron. The reduced recombination velocity of the (−201) face was estimated to be approximately ten for the plan-view measurement, whereas that of ten or more was assumed for the cross-sectional measurement. No inconsistency was observed, but the low-energy plan-view measurement is considered more suitable for investigating the surface recombination velocity.
Strongly coupled surface plasmon resonance modes at both FF and SH in clusters of symmetrically distributed metallic nanospheres
Authors: Zhang Jun , Li Mengting , Dong Beibei , Wang Yajing , Xia Shiqiang , Lu Hai , Liu Yufang , Yu Kun 
Published: September 2022

Abstract
Plasmonic nanoclusters play an important role in the rapid development of application of nanophotonics. In this article both the fundamental-frequency (FF) and second-harmonic (SH) responses of the complex nanoclusters (tetramer, hexamer, and octamer), constructed by coupled spherical plasmonic nanoparticles, are theoretically investigated. By using the multiple scattering algorithm, we present the comprehensive numerical analysis of the physical mechanisms pertaining to the linear and nonlinear coupled-plasmon modes, including ‘hot spot’ modes (HSMs) and ‘whispering-gallery’ modes (WGMs). Different from the symmetric coupling of plasmonic eigenmodes excited by the nanodimer, our analysis reveals that such coupled modes from the nanomultimers are the result of the ‘hybridization’ of symmetric and asymmetric coupling between adjacent dipole or higher-order multipole moments. Also, the remarkable enhancement as large as 3–4 orders of magnitude is achieved for the SH intensity when employing the plasmonic HSMs or WGMs at the FF. Interestingly, the nonlinear plasmonic HSMs and WGMs (the maximum Q up to 4800) can also be obtained by elaborately designing the system geometry. In addition, the resonant wavelengths of such coupled-plasmon modes can be linearly modulated within a broad range. These numerical results have potential applications in surface optical microscopy, plasmonic sensor and nanolaser.
Multivariate time-varying complex signal processing framework and its application in rotating machinery rotor-bearing system
Authors: Huang Jie , Cui Xiaolong , Li Chaoshun , Xiao Zhihuai , Chen Qiming 
Published: September 2022

Abstract
Affected by multi-field coupling factors, the vibration response of rotating machinery similar to the hydro-generator unit often exhibits strong time-varying frequency components, which makes rotor fault detection more challenging. The fusion analysis of the vibration signals of multiple bearing sections of the rotor has been proved to be a very effective method for rotor vibration fault diagnosis. However, how to more accurately and synchronously extract the instantaneous features of rotor non-stationary vibration signals associated with multiple sections has been unresolved. To this end, a framework for multivariate time-varying complex signal decomposition of the rotor-bearing system (RBS) is proposed, namely multivariate complex nonlinear chirp mode decomposition. First, the decomposition of multivariate time-varying complex signals is realized by two-stage processing. Second, instantaneous orbit features (IOFs) are obtained through the proposed framework. Finally, a three-dimensional instantaneous orbit map reflecting the time-varying process is constructed through the IOFs. The framework not only realizes the decomposition of the multi-channel time-varying complex signals of the rotor but also simultaneously extracts the instantaneous features of the multi-channel signals. In addition, it also realizes the description of the instantaneous vibration state of the RBS in the non-stationary process (such as startup and shutdown). Simulation experiments show that the framework is superior to other multi-channel signal processing methods in processing time-varying complex signals. The results based on field-measured signals show that the framework can guide the real-time analysis of the signals generated by rotating machinery, which improves the intuition of condition monitoring.
Simulation of lithium flow, redeposition, and vapor shielding in liquid lithium divertor of T-15MD tokamak with SOLPS 4.3 code
Authors: Marenkov E D , Pshenov A A , Kukushkin A S 
Published: September 2022

Abstract
The erosion module of the SOLPS 4.3 code package for the liquid Li divertor target is developed to include the thermal sputtering, evaporation, and prompt redeposition effects. Eroded Li atoms are treated within a fully kinetic approach. Simulations for the T-15MD tokamak with liquid Li divertor targets are performed for various operational regimes. The main parameters characterizing the divertor operation are identified. The Li shielding effect is found significant at the input power P
SOL > 15 MW. The target conditions remain reasonable in terms of both the erosion rate and target temperature but core plasma dilution with Li remains a problem. The Li flow patterns in the scrape-of-layer (SOL) are analyzed in detail. About 80% of eroded Li is redeposited back on the target. The energy dissipated per an eroded Li particle, E
sh, is calculated and its values are in the range of 100–200 eV. These values are 2–4 times lower than those obtained from a simple 0D estimation of E
sh. Therefore, relying on simple 0D models for the analysis of Li divertor performance may cause an overestimation of the shielding efficiency.
Determination of organic impurities by plasma electron spectroscopy in nonlocal plasma at intermediate and high pressures
Authors: Zhou Chen , Yao Jingfeng , Saifutdinov Almaz I , Kudryavtsev Anatoly A , Yuan Chengxun , Ma Guowei , Dou Zhiyu , Cao Jingjie , Ma Mingxi , Zhou Zhongxiang 
Published: September 2022

Abstract
This study aims to improve impurity analysis by plasma electron spectroscopy for organic molecules. Various impurities can be registered simultaneously in one measurement, because the appearance energies of the characteristic Penning electrons vary for different chemical compounds. Herein, experimental studies were conducted on helium with alcohol vapor impurities in a nonlocal negative glow plasma of a short glow micro-discharge with an increase in pressure from 15 Torr to 150 Torr. As a result, plasma electron spectroscopy enables the detection of gas impurities in high-pressure (even at atmospheric) environments, which eliminates the need for expensive and cumbersome gas pumping systems and expands the scope of the method.
Bosonic fields in states with undefined particle numbers possess detectable non-contextuality features, plus more
Authors: Schlichtholz Konrad , Mandarino Antonio , Żukowski Marek 
Published: September 2022

Abstract
The paradoxical features of quantum theory are usually formulated for fixed number of particles. While one can now find a formulation of Bell’s theorem for quantum fields, a Kochen–Specker-type reasoning is usually formulated for just one particle, or like in the case of Peres–Mermin square for two. Is it possible to formulate a contextuality proof for situation in which the numbers of particles are fundamentally undefined? We introduce a representation of the

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u

(

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algebra in terms of boson number states in two modes that allows us to assess nonclassicality of states of bosonic fields. This representation allows to show contextuality, and is efficient to reveal violation of local realism, and to formulate entanglement indicators. A form of an non-contextuality inequality is derived, giving a bosonic Peres–Mermin square. The entanglement indicators are built with Pauli-like field observables. The non-clasicality indicators are effective. This is shown for the 2 × 2 bright squeezed vacuum state, and a recently discussed bright-GHZ state resulting from multiple three photon emissions in a parametric process.
Expansion of a quantum gas in a shell trap
Authors: Guo Yanliang , Mercado Gutierrez Emmanuel , Rey David , Badr Thomas , Perrin Aurélien , Longchambon Laurent , Bagnato Vanderlei Salvador , Perrin Hélène , Dubessy Romain 
Published: September 2022

Abstract
We report the observation of the controlled expansion of a two-dimensional (2D) quantum gas confined onto a curved shell-shaped surface. We start from the ellipsoidal geometry of a dressed quadrupole trap and introduce a novel gravity compensation mechanism enabling to explore the full ellipsoid. The zero-point energy of the transverse confinement manifests itself by the spontaneous emergence of an annular shape in the atomic distribution. The experimental results are compared with the solution of the three-dimensional Gross–Pitaevskii equation and with a 2D semi-analytical model. This work evidences how a hidden dimension can affect dramatically the embedded low-dimensional system by inducing a change of topology.