bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent observations of the rotation of distant galaxies and the implication for dark matter
Authors: Nelson A. H. , Williams P. R. 
Published: May 2024

Context. Recent measurements of gas velocity in the outer parts of high redshift galaxies suggest that steeply falling rotation curves may be common or even universal in these galaxies, in contrast to the near universal flat, non-declining rotation curves in nearby galaxies.
Aims. The aim was to investigate the implications of these postulated steeply falling rotation curves for the role of dark matter in galaxy formation.
Methods. Using an established computer code, the collapse of dark matter and baryonic matter together, starting with a variety of initial conditions, was simulated for comparison with the observed rotation curves. A simulation of collapsing baryonic matter on its own without dark matter was also carried out. The masses of the protogalaxies were chosen to produce a stellar disc in the same mass range as the observed galaxies at roughly the same redshift.
Results. As soon as a smooth stellar disc was formed in the baryonic matter, with properties similar to the observed high redshift galaxies, the computed rotation curves were without exception relatively flat to large radius in the gas disc. Only a simulation without a dark matter halo was able to reproduce the observed rotation curves.
Conclusions. This implies that if the high redshift steeply falling rotation curves turn out to be common, then the standard scenario of galaxy formation by baryonic matter falling into the potential well of a massive dark matter halo must be wrong, unless there is pressure support via velocity dispersion significantly higher than has so far been observed or resulted from our simulations. It would also imply that for these galaxies the flat rotation curves at low redshift must be due to dark matter which has subsequently fallen into the galactic potential well, or there must be some other explanation for their contemporary flat rotation curves other than dark matter.
Whistler-mode waves in the tail of Mercury’s magnetosphere: A numerical study
Authors: Ballerini Giulio , Lavorenti Federico , Califano Francesco , Henri Pierre 
Published: May 2024

Context. Mercury presents a highly dynamic, small magnetosphere in which magnetic reconnection plays a fundamental role.
Aim. We aim to model the global characteristics of magnetic reconnection in the Hermean environment. In particular, we focus on waves observed during the third BepiColombo flyby.
Method. In this work, we used two fully kinetic three-dimensional (3D) simulations carried out with the iPIC3D code, which models the interaction of the solar wind with the Hermean magnetosphere. For the simulations, we used southward solar wind conditions that allow for a maximum magnetic coupling between the solar wind and the planet.
Results. Our simulations show that a significant wave activity, triggered by magnetic reconnection, develops near the diffusion region in the magnetotail and propagates at large scales in the night-side magnetosphere. We see an increase in electron temperature close to the diffusion region and we specifically observe narrowband whistler waves developing near the reconnection region. These waves propagate nearly parallel to the magnetic field at frequency f ∼ 0.5fce. In addition to the electromagnetic component, these waves also exhibit an electrostatic one. Furthermore, we observe a strong electron temperature anisotropy, suggesting it plays a role as the source of these waves.
Rapidly rotating Population III stellar models as a source of primary nitrogen
Authors: Tsiatsiou Sophie , Sibony Yves , Nandal Devesh , Sciarini Luca , Hirai Yutaka , Ekström Sylvia , Farrell Eoin , Murphy Laura , Choplin Arthur , Hirschi Raphael , Chiappini Cristina , Liu Boyuan , Bromm Volker , Groh Jose , Meynet Georges 
Published: May 2024

Context. The first stars might have been fast rotators. This would have important consequences for their radiative, mechanical, and chemical feedback.
Aims. We discuss the impact of fast initial rotation on the evolution of massive Population III models and on their nitrogen and oxygen stellar yields.
Methods. We explore the evolution of Population III stars with initial masses in the range of 9 M⊙ ≤ Mini ≤ 120 M⊙, starting with an initial rotation on the zero-age main sequence equal to 70% of the critical one.
Results. We find that with the physics of rotation considered here, our rapidly rotating Population III stellar models do not follow a homogeneous evolution. They lose very little mass in the case in which mechanical winds are switched on when the surface rotation becomes equal to or larger than the critical velocity. The impact on the ionising flux appears to be modest when compared to moderately rotating models. Fast rotation favours, in models with initial masses above ∼20 M⊙, the appearance of a very extended intermediate convective zone around the H-burning shell during the core He-burning phase. This shell has important consequences for the sizes of the He- and CO-cores, and thus impacts the final fate of stars. Moreover, it has a strong impact on nucleosynthesis, boosting the production of primary 14N.
Conclusions. Fast initial rotation significantly impacts the chemical feedback of Population III stars. Observations of extremely metal-poor stars and/or starbursting regions are essential to provide constraints on the properties of the first stars.
Estimation of the lateral mis-registrations of the GRAVITY+adaptive optics system
Authors: Berdeu A. , Bonnet H. , Le Bouquin J.-B. , Édouard C. , Gomes T. , Shchekaturov P. , Dembet R. , Paumard T. , Oberti S. , Kolb J. , Millour F. , Berio P. , Lai O. , Eisenhauer F. , Garcia P. , Straubmeier C. , Kreidberg L. , Hönig S. F. , Defrère D. 
Published: May 2024

Context.The GRAVITY+ upgrade implies a complete renewal of its adaptive optics (AO) systems. Its complex design, featuring moving components between the deformable mirrors and the wavefront sensors, requires the monitoring and auto-calibrating of the lateral mis-registrations of the system while in operation.Aims.For preset and target acquisition, large lateral registration errors must be assessed in open loop to bring the system to a state where the AO loop closes. In closed loop, these errors must be monitored and corrected, without impacting the science.Methods.With respect to the first requirement, our method is perturbative, with two-dimensional modes intentionally applied to the system and correlated to a reference interaction matrix. For the second requirement, we applied a non-perturbative approach that searches for specific patterns in temporal correlations in the closed loop telemetry. This signal is produced by the noise propagation through the AO loop.Results.Our methods were validated through simulations and on the GRAVITY+ development bench. The first method robustly estimates the lateral mis-registrations, in a single fit and with a sub-subaperture resolution while in an open loop. The second method is not absolute, but it does successfully bring the system towards a negligible mis-registration error, with a limited turbulence bias. Both methods proved to robustly work on a system still under development and not fully characterised.Conclusions.Tested with Shack-Hartmann wavefront sensors, the proposed methods are versatile and easily adaptable to other AO instruments, such as the pyramid, which stands as a baseline for all future AO systems. The non-perturbative method, not relying on an interaction matrix model and being sparse in the Fourier domain, is particularly suitable to the next generation of AO systems for extremely large telescopes that will present an unprecedented level of complexity and numbers of actuators.
Deep tomography for the three-dimensional atmospheric turbulence wavefront aberration
Authors: Zhang Lingxiao , Zhang Lanqiang , Zhong Libo , Rao Changhui 
Published: May 2024

Context.Multiconjugate adaptive optics (MCAO) can overcome atmospheric anisoplanatism to achieve high-resolution imaging with a large field of view (FOV). Atmospheric tomography is the key technology for MCAO. The commonly used modal tomography approach reconstructs the three-dimensional atmospheric turbulence wavefront aberration based on the wavefront sensor (WFS) detection information from multiple guide star (GS) directions. However, the atmospheric tomography problem is severely ill-posed. The incomplete GS coverage in the FOV coupled with the WFS detection error significantly affects the reconstruction accuracy of the three-dimensional atmospheric turbulence wavefront aberration, leading to a nonuniform aberration detection precision over the whole FOV.Aims.We propose an efficient approach for achieving accurate atmospheric tomography to overcome the limitations of the traditional modal tomography approach.Methods.We employed a deep-learning-based approach to the tomographic reconstruction of the three-dimensional atmospheric turbulence wavefront aberration. We propose an atmospheric tomography residual network (AT-ResNet) that is specifically designed for this task, which can directly generate wavefronts of multiple turbulence layers based on the Shack-Hartmann (SH) WFS detection images from multiple GS directions. The AT-ResNet was trained under different turbulence intensity conditions to improve its generalization ability. We verified the performance of the proposed approach under different conditions and compared it with the traditional modal tomography approach.Results.The well-trained AT-ResNet demonstrates a superior performance compared to the traditional modal tomography approach under different atmospheric turbulence intensities, various turbulence layer distributions, higher-order turbulence aberrations, detection noise, and reduced GSs conditions. The proposed approach effectively addresses the limitations of the modal tomography approach, leading to a notable improvement in the accuracy of atmospheric tomography. It achieves a highly uniform and high-precision wavefront reconstruction over the whole FOV. This study holds great significance for the development and application of the MCAO technology.
Introduction to the special issue: Implementing environmental criminology for crime prevention
Authors: Ceccato Vania 
Published: May 2024

AbstractThis introduction aims to showcase the articles of the special issue and highlights the expansive field of environmental criminology, underscoring its role in understanding and preventing crime through situational and environmental strategies. This collection of articles covers a wide array of research from the USA, Sweden, Australia, New Zealand, and Uruguay, demonstrating the global application of environmental criminology principles. Contributions from various disciplines illustrate the field’s multidisciplinary approach to tackling crime, particularly in the face of challenges posed by climate change and the need for social and economic sustainability.
Collaborative positioning for emergency rescuers based on INS, GPS and ZigBee
Authors: Ji Miaoxin , Ren Guihui , Zhang Huijuan , Ren Renhao 
Published: May 2024

Abstract
Multi-person cooperative positioning is one of the main techniques to improve the success rate of search and rescue. Nevertheless, current integrated positioning solutions for ZigBee and inertial navigation system (INS) are insufficiently versatile and commonly necessitate pre-existing infrastructure within the area. In this study, it is not necessary to install ZigBee positioning anchors in the environment in advance, and all positioning devices were mounted on rescuers, in contrast to previous positioning methods. First, an improved time difference of arrival (TDOA) method is proposed, which weights the position coordinates to minimize positioning errors. Then, the position data of the commander and the rescuers are substituted into the hyperbolic equations of the improved TDOA method, and the initial position of the rescuers is solved by Taylor method. Finally, based on the initial position, an improved Extended Kalman filter (EKF) position update technology is proposed, which uses ZigBee positioning system to monitor the east and north position of rescuers, and uses barometers to measure the altitude of rescuers. The magnetometers are used to limit the heading angle of the rescuers, so as to realize the high-precision 3D positioning of the emergency rescuers in the harsh environment. In this paper, three different scenarios are used to verify the effectiveness of the proposed method. The experimental results demonstrate that, when compared to the inertial positioning method, the traditional TDOA method, and the cooperative positioning method based on the relative ranging constraints of UWB and INS, respectively, the average positioning accuracy of the proposed method is 68.58%, 48.71%, and 13.59% higher.
Quasi-plastic deformation mechanisms and inverse Hall–Petch relationship in nanocrystalline boron carbide under compression
Authors: Yue 岳 Zhen 珍 , Li 李 Jun 君 , Liu 刘 Lisheng 立胜 , Mei 梅 Hai 海 
Published: May 2024

Abstract
Grain boundaries (GBs) play a significant role in the deformation behaviors of nanocrystalline ceramics. Here, we investigate the compression behaviors of nanocrystalline boron carbide (nB4C) with varying grain sizes using molecular dynamics simulations with a machine-learning force field. The results reveal quasi-plastic deformation mechanisms in nB4C: GB sliding, intergranular amorphization and intragranular amorphization. GB sliding arises from the presence of soft GBs, leading to intergranular amorphization. Intragranular amorphization arises from the interaction between grains with unfavorable orientations and the softened amorphous GBs, and finally causes structural failure. Furthermore, nB4C models with varying grain sizes from 4.07 nm to 10.86 nm display an inverse Hall–Petch relationship due to the GB sliding mechanism. A higher strain rate in nB4C often leads to a higher yield strength, following a 2/3 power relationship. These deformation mechanisms are critical for the design of ceramics with superior mechanical properties.
Test result of the new ASD2 chips for Phase-II upgrade of the ATLAS MDT chambers at HL-LHC
Authors: Penski K. ,   the ATLAS Muon Spectrometer System collaboration
Published: May 2024

Abstract
For the Phase-II upgrade of the ATLAS Muon Spectrometer to High-Luminosity LHC, new front-end readout electronics for the Monitored Drift Tube chambers is required, as the old one no longer meets the demands. The first stage in the Monitored Drift Tubes readout chain is the Amplifier-Shaper-Discriminator chip. For the upgrade, the new ASD2 ASIC chip in IBM 130 nm CMOS technology has been developed. For the ATLAS experiment, 80000 ASD2 chips are produced, which have to be tested before integration in order to obtain the required 50000 well-performing chips in the end. Using a prototype tester board and pre-production ASD2 chips, the overall performance and the influence on programmable parameters is investigated. Based on these results, 1775 production chips are tested to define final optimized cut values for the automated production testing of all chips in the company.
Validation of the diamond detectors for the Super Fragment Separator beam diagnostics
Authors: Alfonsi M. , Nociforo C. , Kiš M. , Träger M. , Galvis Tarquino J. , Blatz T. , Karagiannis C. , Winkler M. , Simon H. 
Published: May 2024

Abstract
The Super-FRS at the FAIR accelerator complex will adopt Chemical
Vapor Deposition diamond detectors as radiation-hard particle rate
counters.
Their role will be to monitor the beam transmission for beams
with ions rates up to 107 ions/spill and to calibrate the other
beam diagnostics devices that are in duty at higher beam
intensities.
The target vacuum chamber of the Super-FRS hosts a 7 × 7 mm2 single crystal diamond and a 25 × 25 mm2 polycrystalline
diamond: they are required to detect crossing particles with high
efficiency (> 98%) in the case of heavy ion species (Ar to U), and
to stand for several years in an environment in which they can
potentially accumulate a dose of a few MGy per year.
Laboratory measurements and beam test campaigns were arranged in the
past years for the validation of the proposed sensors, in particular
for the case of the polycrystalline technology.
Here we report the outcome of the irradiation of a sensor based on a
20 × 20 mm2 polycrystalline diamond produced by Element
Six, with high intensity 1 GeV/nucleon Pb and U beams at GSI
(Darmstadt). The detector signal shape characteristics and the ion
counting efficiency have been monitored by interleaving periods of low
ions rates, to evaluate possible damages or performance degradation
during and after a total bombardment of about 6 × 1011 heavy ions.
Design and development of square stub loaded band pass filter with quality factor analysis
Authors: Thotakura Haritha , Swamy Banothu Y.V.N.R. , Vineetha K.V. , Madhav B.T.P. , Das Sudipta 
Published: May 2024

Abstract
In this paper, a compact square stub-loaded band pass filter (BPF) is designed and investigated for quality factor improvement analysis. A detailed analysis has been presented to demonstrate the superior power handling capability of the proposed microstrip bandpass filter without any degradation in its electrical performance parameters. For this purpose, square-type stubs are incorporated in the proposed bandpass filter which reduced the maximum peak voltage and increased the high peak threshold, instead of using sharp edges. Also, an in-depth analysis of peak voltage with a center frequency of 2.1 and 4.2 have been carried out by considering some parameters like pressure and quality. The proposed bandpass filter shows minimum peak voltage of 1.61 V and 1.59 V across the frequency of 2.1 GHz and 4.2 GHz which covers the application of mobile and radio altimeters. The designed BPF shows the minimum heat generation of 0.29 and 0.89 per watt at the resonating frequencies of 2.1 and 4.2 GHz. Furthermore, the proposed bandpass filter presents an in-depth analysis of several characteristic parameters such as return loss, insertion loss, power loss, delay in group and phase, current distribution, H and E field distribution and maximum power loaded and unloaded quality factor.
Improvement on the linearity response of PandaX-4T with new photomultiplier tube bases
Authors: Luo Lingyin , Fang Deqing , Han Ke , Huang Di , Shang Xiaofeng , Wang Anqing , Wang Qiuhong , Wang Shaobo , Wang Siguang , Xiao Xiang , Yan Binbin , Yan Xiyu 
Published: May 2024

Abstract
With the expanding reach of physics, xenon-based detectors
such as PandaX-4T in the China Jinping Underground Laboratory aim to
cover an energy range from sub-keV to multi-MeV. A linear
response of the photomultiplier tubes (PMTs) is required for both
scintillation and electroluminescence signals. Through a dedicated
bench test, we investigated the cause of the non-linear response in
the Hamamatsu R11410-23 PMTs used in PandaX-4T. The saturation and
suppression of the PMT waveform observed during the commissioning of
PandaX-4T were caused by the high-voltage divider base. The bench
test data validated the de-saturation algorithm used in the
PandaX-4T data analysis. We also confirmed the improvement in
linearity of a new PMT base design with three more low radioactivity
capacitors at later dynodes, which will be used to upgrade the PMT
readout system in PandaX-4T.
Development of a low-pressure Multi-Mesh THGEM detector for fission experiments at FRIB
Authors: Harca I.M. , Cortesi M. , Chyzh R. , Brown K. , McCormick C.E. , Basson M.J. 
Published: May 2024

Abstract
A small-area imaging detector prototype for position measurement of fission fragments produced in low energy heavy-ion reactions is presented in this study. The detector readout is equipped with a 2-dimensional, position-sensitive gaseous avalanche readout based on the novel Multi-Mesh Thick-GEM (MM-THGEM), and is coupled to a delay-line board for particle localization. The prototype has an effective area of 10 × 10 cm2 and is operated in isobutane at low pressure (7–10 Torr). We present and discuss a series of systematic evaluation tests performed by irradiating the detector with α-particles and fission fragments emitted by small-rate sources (241Am, 249Cf and 252Cf). Position and time resolutions of about 0.42 mm and 1 ns were achieved, respectively. This work serves as a benchmark for the development of a large-scale array of detectors for experiments with fission and fission-like reaction products at the Facility for Rare Isotope Beams (FRIB).
Comment on ‘Self-thinning forest understoreys reduce wildfire risk, even in a warming climate’
Authors: Miller Ben P , Fontaine Joseph B , Tangney Ryan , McCaw Lachie , Cruz Miguel G , Hollis Jennifer J 
Published: May 2024

Abstract
In this comment we examine a recent study published in Environmental Research Letters that analysed fire history data from forests in Western Australia to suggest that changes in forest structure result in a long-term reduction of fire risk after 56 years since last fire. We examine the data underpinning this study and find that its strongly skewed sample size distribution creates a bias to the extent that the analytical approach would find a pattern of declining fire risk even when there was no decline. Moreover, the very small sample sizes of the longest unburned forests mean that fire mapping errors as small as 1–2 ha can reverse key findings. With documented mapping errors orders of magnitude larger, the dataset is not robust to analysis at this level of precision. An appropriate conclusion, taking into account these detection and sensitivity issues, would be that likelihood of subsequent wildfire is reduced in the first ∼6 years following fire, and remains fairly consistent at a higher level for at least the next 3 decades, with no evidence for a long-term reduction of fire risk. This is relevant given that many fire and forest management decisions are made based on scientific literature. Rather than wildfire risk reducing with increasing time since fire, our projections indicate that ceasing active fire management in the sampled forests could result in landscape wildfire extent 25%–65% above current levels. We recommend further steps that would help provide sound, evidence-based knowledge to inform science, management, and policy.
Quality of plant-based diets and frailty incidence: a prospective analysis of UK biobank participants
Authors: Maroto-Rodriguez Javier , Ortolá Rosario , García-Esquinas Esther , Kales Stefanos N , Rodríguez-Artalejo Fernando , Sotos-Prieto Mercedes 
Published: May 2024

Abstract

Background
Substantial evidence supports the inverse association between adherence to healthy dietary patterns and frailty risk. However, the role of plant-based diets, particularly their quality, is poorly known.

Objective
To examine the association of two plant-based diets with incidence of physical frailty in middle-aged and older adults.

Design
Prospective cohort.

Setting
United Kingdom

Subjects
24,996 individuals aged 40–70 years, followed from 2009–12 to 2019–22.

Methods
Based on at least two 24-h diet assessments, we built two diet indices: (i) the healthful Plant-based Diet Index (hPDI) and (ii) the unhealthful Plant-based Diet Index (uPDI). Incident frailty was defined as developing ≥3 out of 5 of the Fried criteria. We used Cox models to estimate relative risks (RR), and their 95% confidence interval (CI), of incident frailty adjusted for the main potential confounders.

Results
After a median follow-up of 6.72 years, 428 cases of frailty were ascertained. The RR (95% CI) of frailty was 0.62 (0.48–0.80) for the highest versus lowest tertile of the hPDI and 1.61 (1.26–2.05) for the uPDI. The consumption of healthy plant foods was associated with lower frailty risk (RR per serving 0.93 (0.90–0.96)). The hPDI was directly, and the uPDI inversely, associated with higher risk of low physical activity, slow walking speed and weak hand grip, and the uPDI with higher risk of exhaustion.

Conclusions
In British middle-age and older adults, greater adherence to the hPDI was associated with lower risk of frailty, whereas greater adherence to the uPDI was associated with higher risk.