Physics Research Research Articles

Editorial: Driving towards a more diverse space physics research community—perspectives, initiatives, strategies, and actions

Editorial: Driving towards a more diverse space physics research community—perspectives, initiatives, strategies, and actions

Black Holes in Globular Clusters

Black holes are the laboratory for extreme physics research in the universe, and the detection of black holes is one of the most cutting-edge international scientific goals at present. Globular clusters are old, self-gravity-bound object systems in the Milky Way that contain millions of stars with a high stellar densities inside. Hundreds of pulsar objects have been observed in globular clusters, but the existence of black holes in globular clusters remains an unsolved mystery. A globular cluster may have an intermediatemass black hole at its centre, with masses ranging from 1, 000 to 10, 000 times solar masses. At the same time, there may be a large number of stellar black holes in globular clusters, which will affect the evolution of globular clusters and form. some special objects in globular clusters, which can be observed and confirmed by astronomical observation equipment. This paper will focus on the possible observational features of the presence of black holes in globular clusters and their effects on the properties of globular clusters. Black holes are coupled with their host globular clusters through dynamics, which are important sites for the formation of black hole X-ray binaries and gravitational wave sources, and black holes change the dynamical structure and evolutionary processes of their host clusters. Therefore, searching for X-ray sources, detecting gravitational wave signals, and studying the characteristics of globular clusters are important astronomical evidence for detecting black holes in globular clusters.

Magnetic Topological Insulator MnBi2Te4 Nanosheets for Femtosecond Pulse Generation.

The van der Waals layered material MnBi2Te4, as a magnetic topological insulator, has attracted tremendous interest for novel physics research in the fields of condensed matter physics and materials science. However, the nonlinear optical properties of MnBi2Te4 and its applications in ultrafast optics have rarely been explored. In this study, high-quality MnBi2Te4 nanosheets have been successfully synthesized by the self-flux method. The morphology, chemical composition, magnetic properties, and nonlinear optical characteristics were systematically investigated. The magnetic transition of MnBi2Te4 was confirmed by a low-temperature spatially resolved spectroscopic technique. The saturable absorption property of MnBi2Te4 was measured by a balanced twin-detector system with a modulation depth of 4.5% and a saturation optical intensity of 2.35 GW/cm2. Furthermore, by inserting the MnBi2Te4-based saturable absorber, a soliton mode-locking laser operating at 1558.8 nm was obtained with a pulse duration of 331 fs. This research will pave the way for applications of the magnetic TI MnBi2Te4 in nonlinear optics and photonics.

Deep Variational Free Energy Approach to Dense Hydrogen.

We developed a deep generative model-based variational free energy approach to the equations of state of dense hydrogen. We employ a normalizing flow network to model the proton Boltzmann distribution and a fermionic neural network to model the electron wave function at given proton positions. By jointly optimizing the two neural networks we reached a comparable variational free energy to the previous coupled electron-ion MonteCarlo calculation. The predicted equation of state of dense hydrogen under planetary conditions is denser than the findings of abinitio molecular dynamics calculation and empirical chemical model. Moreover, direct access to the entropy and free energy of dense hydrogen opens new opportunities in planetary modeling and high-pressure physics research.

Predictive Value of In-Program Academic Variables for Future Clinical Education Performance in Physical Therapist Education: An Exploratory Study

Introduction. The purposes of this study were to (1) explore the relationship of preclinical assessment outcomes and grade point averages (GPAs) with full-time clinical education experience (CEE) performance and (2) determine the predictive value of associated variables to full-time CEE performance. Review of Literature. In-program academic variables such as performance tests, comprehensive examinations, and GPAs reflect a measure of student performance before clinical education. Limited and conflicting physical therapist education research exists examining the relationship between preclinical in-program academic variables and CEE performance. Subjects. A retrospective convenience sample of 130 graduated PT student academic records with expected graduation years of 2018, 2019, and 2020. Methods. Academic records related to performance test outcomes, cumulative program GPAs, utilization of a practical retake appeal policy, and comprehensive examination performance were correlated with CEE performance. A dichotomous ordinal rating scale quantified CEE performance per full-time experience based on the presence of a learning contract. Overall CEE performance was defined as the percentage from the combined CEE performance scores across all experiences. Data analyses included Pearson's correlation coefficient, Spearman's rho, and a multiple linear regression analysis. Results. Ten of 25 course-specific performance tests had significant associations with CEE performance. Cumulative GPA and the practical retake appeal were significantly associated with the CEE III score and overall CEE performance. The practical retake appeal was a significant contributor to clinical performance, explaining 5.3% of the variance (β = 0.24, P = .01, 95% CI 0.01 to 0.09, part correlation = 0.23, tolerance = 0.91). Discussion and Conclusion. These findings support the use of performance tests as an effective assessment strategy before CEEs but only represent one aspect of the full picture of readiness to practice. Academic progression policies can offer a mechanism for early identification to support at-risk students before the CEEs.

Optical levitation in high vacuum using a 0.9-numerical-aperture lens

Nanoparticles levitated in high vacuum are isolated from the surrounding environment and thus can be used in various applications, including quantum physics research. We demonstrated optical levitation of a nanoparticle, which was trapped without cooling at a pressure of 4.5 × 10−3 Pa, using a single aspheric lens with a large numerical aperture (= 0.9) and 1030-nm laser. We also activated parametric feedback cooling to trap the particle at a pressure of 5.8 × 10−4 Pa. This experimental system will be useful for studying nanoparticles in ultrahigh vacuum and for building a mixed system with laser-cooled atoms.

Further physical research about soliton structures and phase portraits in nonlinear fractional electrical transmission line model

This paper presents several novel contributions in the field of nonlinear fractional low-pass electrical transmission line model (NFLETLM). Firstly, using the modified (G′G2)-expansion method and the extended modified Jacobi elliptic expansion method, we discovered new and accurate solutions for NFLETLM, which have not been reported in the existing literature (Tala-Tcbuc et al. 2014; Nuruzzaman et al. 2021). These solutions, denoted as U3,U4,U7,U8,U9,U10,U13,U14 and UJ1,UJ2,UJ3,UJ4 represent novel contributions to the fields. Secondly, by utilizing computer simulations, we observed various intriguing phenomena in the wave solution graphs, such as anti-kink waves, periodic waves, intense singular periodic waves, bright singular wave solutions, multi-periodic waves, intense double periodic waves, and alternating patterns of light and shade waves. These findings shed light on previously unexplored aspects of the problem. Thirdly, through an extensive study on the newly discovered solutions, we provided a comprehensive understanding of the solitons inherent in the NFLETLM, including comparison with other derivative solutions. Our conformable fractional derivative solutions showed similarities to beta derivative solutions, distinguishing them from Riemann–Liouville derivative solutions. Lastly, we explored the phase portrait, bifurcation analysis, sensitivity, and potential chaotic behaviors of the NFLETLM, which have not been addressed in previous works (Tala-Tcbuc et al. 2014; Nuruzzaman et al. 2021). This innovative contribution expands our understanding of the NFLETLM model and uncovers new dynamics and phenomena.

S7-1 Physical activity and planetary health

Abstract The symposium intends to showcase research that seeks to connect physical activity to planetary health. Such research is warranted by the thread of global warming and the loss of biodiversity, but at the same time it is still in its early stages and many open questions remain. Concepts such as one health and planetary health have now been developed and provide more general frameworks on how to map the impacts of (health) behavior on the environment. However, while these frameworks are still quite new for our field of study, it is worthwhile exploring how they can be utilized in our research. After a brief introduction of the interconnections between physical activity and planetary health, it is the objective of the symposium to present some projects that have begun to go beyond individual and public health and also consider issues of planetary health. This research will touch upon the issue of active transport, but also on the carbon footprint caused by sport and exercise. The symposium will give room for debate, to also allow raising some of the more difficult questions such as on how to deal with types of sport and exercise, that might be good for individual and public health, but have negative effects on the environment. Further objectives of the symposium are to create a better understanding on how the issue of planetary health might be integrated in physical activity research. Also, by bringing together researchers who are interested and have worked on this topic, to foster networking and collaboration.

O.6.3-10 Investigating the impact of a school garden intervention on children’s school motivation, climate literacy, food literacy and physical activity: the FoodACT protocol

Abstract Background Globally, too many children are not sufficient physically active and have unhealthy food habits with the highest prevalence seen in families with low socio-economic-status (SES). Previous research has stated that schools are considered a key setting for promoting children physical activity (PA), food literacy (FL) and to improve their social health. School gardens is exactly such an intervention where teaching is relocated to an outdoor setting. Relocation of teaching, which is a central ingredient of school gardens, has shown to be positively related to increased PA in both boys and girls during the school day. School gardens aim towards practical experience and education in food and climate. PA is not I focus, but the school garden learning environment provides pupils opportunities to be active. Therefore, the FoodACT study aims to investigate how a school gardening intervention impact pupils school motivation, CL, FL and PA with a special attention on children with low SES. Methods The FoodACT study is designed in three sub-studies. An efficacy study, quantifying the effects of school gardens using a pre-post quasi-experimental design measuring the pupils’ FL, CL and SM. A within-subject-design association study, quantifying the influence of the school garden activities on pupils PA at two sessional periods during the intervention. An association study, investigating the contextual characteristics of the school garden activities using the systematic observations instrument, The Physical Activity Research and Assessment tool for Garden Observation (PARAGON), which can capture pupils’ movements and motions categorised in ‘overall PA-level’, ‘garden-related tasks’, ‘garden related motions’, ‘social associations’, and ‘interaction’. The observations is supplemented by pupil focus-group interviews about their experience of the school garden intervention. Results Study design, recruitment experience and pilot-study data on PA and garden activity observations will be presented. Funding The FoodACT study is funded by the Novo Nordisk Foundation (Grant no: 077522).

S10-1 Research on sub-national initiatives in HEPA policy making from Europe, Japan and the USA

Abstract The importance of local governments' engagement in physical activity promotion at local level has been acknowledged and advocated by the World Health organization in documents such as: “Promoting physical activity and active living in urban environments: the role of local governments” or “Global action plan on physical activity 2018–2030: more active people for a healthier world”. However, given the relative “youngness” of the physical activity policy research domain, the local level initiatives have been underrepresented in the scientific literature. The current symposium aims to present a number of diverse initiatives to promote health enhancing physical activity at sub-national level, each having a very unique context and approach. The paper from Eastern Michigan University presents the actions taken to implement Active People, Healthy Nation (APHN) program in geographic areas in Michigan where the priority population (Asian Americans) lives and the outcomes of this initiative. The contribution from Japan describes the process of developing and applying the L-PAT (local policy audit tool), an instrument comprising 11 items based on WHO’s HEPA Policy Audit Tool (HEPA PAT) and the results of this survey within 47 Japanese prefectures and the C-PAT (city policy audit tool), a 6 items tool, in a selection of 272 Japanese municipalities. The EU study presented in this symposium comprises the results of evaluation, using the CAPLA- Santé, a validated instrument, of local HEPA policies in 4 selected municipalities, one from each of the following countries: Finland, France, Germany, Romania and from one municipality in Japan. The responsibilities of local authorities in health promotion and protection are undeniable. The way the authorities manage to fulfil these responsibilities is gaining more and more interest from various stakeholders from local level activists to researchers and policymakers at national and international level. Local communities are increasingly stimulated to contribute to their own wellbeing, so data on the status quo and progress is needed more than ever. The initial discussion points of the symposium will focus on strengths and weaknesses of the initiatives presented, as well as the potential for knowledge exchange and replication & scaling-up.

An investigation of two integro-differential KP hierarchy equations to find out closed form solitons in mathematical physics

Nonlinear partial differential equations (NLPDEs) are widely utilized in engineering and physical research to represent many physical processes of naturalistic occurrences. In this paper, we investigate two well-known NLPDEs, namely, the (2 + 1)-dimensional first integro-differential KP hierarchy equation and the (2 + 1)-dimensional second integro-differential KP hierarchy equation, through a well-stable algorithm known as the ( G ′ G ′ + G + A ) -expansion approach for the first time. This algorithm is generally based on the expansion of function method and has the advantage of easy implementation and can provide a reliable solution to any NLPDEs. Employing the algorithm, we have been able to perceive the closed form solitons of the two chosen NLPDEs that physically represent the solitary wave solutions like, singular, singular periodic, bell, and anti-bell-shaped types of solitons. Furthermore, we explore the graphical manifestations of the obtained solutions, which are of the mentioned soliton types. From the findings of our in-depth study, we can state that the acquired solutions for the selected two equations may greatly aid to extracting the associated natural phenomena in mathematical physics such as fluid dynamics and ocean engineering.

A Monte Carlo simulation method for polarized gamma-ray nuclear resonance fluorescence

With the rapid development of inverse Compton scattering gamma-ray sources, highly polarized gamma rays play a significant role in fundamental nuclear physics research based on nuclear resonance fluorescence (NRF). To meet the requirements of those applications, especially for guiding experiments and optimizing detection systems, a Monte Carlo simulation method for linearly polarized gamma-ray NRF is developed and implemented in the general-purpose toolkit Geant4. To validate the effectiveness of this method, simulations are compared with both theoretical and experimental results and are found to agree well with both. As a typical application of the linearly polarized gamma-ray NRF technique, a gamma-ray polarization measurement method is proposed in the energy region from hundreds of keV to several MeV, and its feasibility is analyzed based on the developed simulation method. Compared with the conventional Compton scattering method, the analyzing power of the NRF method is improved about 3.7-fold by using a 28Si target, and reaches a value of more than 0.99 at a reasonable data acquisition time.

Physics and Technology Research for Liquid-Metal Divertor Development, Focused on a Tin-Capillary Porous System Solution, at the OLMAT High Heat-Flux Facility

The operation of the Optimization of Liquid Metal Advanced Targets (OLMAT) facility began in April 2021 with the scientific objective of exposing liquid-metal plasma facing components (PFCs) to the particle and power fluxes provided by one of the hydrogen neutral beam injectors of the TJ-II stellarator. The system can deliver heat fluxes from 5 to 58 MW m−2 of high energy hydrogen neutral particles (≤ 33 keV) with fluxes up to 1022 m2 s−1 (containing an ion fraction ≤ 33% in some instances), pulsed operation of 30–150 ms duration and repetition rates up to 2 min−1. These characteristics enable OLMAT as a high heat flux (HHF) facility for PFC evaluation in terms of power exhaust capabilities, thermal fatigue and resilience to material damage. Additionally, the facility is equipped with a wide range of diagnostics that includes tools for analyzing the thermal response of the targets as well as for monitoring atomic/plasma physics phenomena. These include spectroscopy, pyrometry, electrical probing and visualization (fast and IR cameras) units. Such particularities make OLMAT a unique installation that can combine pure technological PFC research with the investigation of physical phenomena such as vapor shielding, thermal sputtering, the formation/characterization of plasma plumes with significant content of evaporated metal and the detection of impurities in front of the studied targets. Additionally, a myriad of surface characterization techniques as SEM/EDX for material characterization of the exposed PFC prototypes are available at CIEMAT. In this article, first we provide an overview of the current facility upgrade in which a high-power CW laser, that can be operated in continuous and pulsed modes (0.2–10 ms), dump and electrical (single Langmuir) probe embedded on the target surface have been installed. This laser operation will allow simulating more relevant heat loading scenarios such as nominal steady-state divertor heat fluxes (10–20 MW m−2 in continuous mode) and transients including ELM loading and disruption-like events (ms time scales and power densities up to GW m−2 range). The work later focuses on the more recent experimentation (2022 fall campaign) where a 3D printed Tungsten (W) Capillary Porous System (CPS) target, with approximated 30 μm pore size and a 37% porosity and filled with liquid tin. This porous surface was a mock-up of the PFC investigated in the ASDEX Upgrade divertor manipulator. The target composed with this element was eventually exposed to a sequence of shots with the maximum heat flux that OLMAT provides (58 ± 14 MWm−2). Key questions as resilience to dry-out and particle ejection of the liquid metal layer, its refilling, the induced damage/modification of the porous W matrix and the global performance of the component are addressed, attempting to shed light on the issues encountered with the PFC at tokamak scale testing.

Preface

On behalf of the Steering Committee, I have the pleasure of welcoming you to the 5th International Conference on Research and Learning of Physics (ICRLP 2022), which will be held hybrid, in Padang, West Sumatra, Indonesia from September 21 to 22, 2022 This 5th ICRCLP is organized by the Department of Physics, Padang State University. The main objective of this conference is to provide a platform for academics, researchers, professional practitioners, observers, teachers and students to present their current research in physics and physics learning. In addition, it also aims to discuss strategic issues in related fields. Therefore, the ICRLP theme for this year is “The Strategic Role of Physics and Physics Education Research in Supporting Sustainable Development Goals”.This topic was brought up because research must continue to be conducted and developed in support of the world development agenda which aims for global human welfare after the Covid-19 pandemic. As a result, one solution to support this goal is the implementation of research that is flexible while still offering novelty or innovation in the field. Furthermore, as the times change, we are expected to be adaptable, and a concept of a human-centered and technology-based society known as the era of society 5.0 has begun to be applied.I would like to express my sincere appreciation to six distinguished experts as our keynote speakers, all the participants, financial sponsors, exhibitors, supporting organizations and all the committee members who have made 5th ICRLP successful. With this strong support, we are sure the 5th ICRLP will be beneficial to all the participants. Finally, I would like to thank the members of reviewers for their kind assistance in reviewing the papers.Pakhrur Razi, Ph.D.General Chair of ICRLP 2022List of Organizing Committee, Editorial Team are available in this pdf.

Preface

The 12th International Physics Seminar (IPS) 2023 was held at Universitas Negeri Jakarta, Indonesia on June 24th, 2023. IPS was organized by the Department of Physics and Department of Physics Education, Faculty of Mathematical and Natural Science, Universitas Negeri Jakarta. This year’s IPS 2023 featured a hybrid format, allowing participants to attend virtually and in person. The seminar covers various topics, such as material physics, instrumentation and computational physics, medical physics & biophysics, earth physics and space science, theory, nuclear and particle physics, energy and environmental physics, and physics education. “The Diversity Research and Development of Physics for Stronger Recovery” is the theme for this year’s seminar. The following scopes were selected to cover most of the scientific program and highlight an area where new ideas have emerged over recent years:1. Material Physics2. Instrumentation and Computational Physics3. Medical Physics & Biophysics4. Earth Physics and Space Science5. Theory, Nuclear, and Particle Physics6. Energy and Environmental Physics7. Physics EducationThe seminar’s itinerary comprised three main segments: opening ceremony, keynote speaker sessions, and oral presentations. The opening session included reports from the Chair, Dean of FMIPA, PSI Physical Society of Indonesia (PSI) Jakarta and Banten Chapter Chair, and the Rector of Universitas Negeri Jakarta, each allotted 5 minutes for their addresses. The second segment shows presentations from keynote speakers, who presented their groundbreaking research within 40-minute time slots, including Q&A sessions. The third segment featured parallel sessions with 15-minute oral presentations from presenters, researchers, and lecturers, followed by discussions. The parallel session was held in a hybrid (13 rooms), which contains three offline rooms and ten virtual rooms, accommodating an average of 14 presenters in each room. Competent moderators and operators guided each parallel room. Special acknowledgment is extended to PSI Jakarta and Banten Chapter for their invaluable support. This essential scientific platform seminar saw an enthusiastic gathering of 233 participants, including students, lecturers, researchers, and practitioners, all actively engaged as presenters and attendees. The Morressier system facilitated the submission of 153 papers, from which 99 were meticulously selected for publication in the Journal of Physics: Conference Series, with a focus on physics and related disciplines. The rigorous assessment conducted by reviewers evaluated the papers based on criteria such as scope, novelty, originality, scientific impact, accuracy, and clarity of expression. We are grateful to all participants from Indonesia and 42 participants from Czech, Turkey, Bahrain, Saudi Arabia, United Arab Emirates, Taiwan, Thailand, Malaysia, Philippines, Pakistan, Vietnam who have joined our seminar. We invite all participants to join us again for the 13th IPS 2024, hosted by the Department of Physics and Department of Physics Education at Universitas Negeri Jakarta.The Chairman,Dr. Firmanul Catur Wibowo12th International Physics Seminar (IPS) The Diversity of Physics Research and Development for Stronger Recovery Proceedings of International Physics Seminar (IPS) 2023Jakarta, IndonesiaJune 24th, 2023List of Editors, Conference Details are available in this pdf.

Modelling Symmetric Ion-Acoustic Wave Structures for the BBMPB Equation in Fluid Ions Using Hirota’s Bilinear Technique

This paper investigates the ion-acoustic wave structures in fluid ions for the Benjamin–Bona–Mahony–Peregrine–Burgers (BBMPB) equation. The various types of wave structures are extracted including the three-wave hypothesis, breather wave, lump periodic, mixed-type wave, periodic cross-kink, cross-kink rational wave, M-shaped rational wave, M-shaped rational wave solution with one kink wave, and M-shaped rational wave with two kink wave solutions. The Hirota bilinear transformation is a powerful tool that allows us to accurately find solutions and predict the behaviour of these wave structures. Through our analysis, we gain a better understanding of the complex dynamics of ion-acoustic waves and their potential applications in various fields. Moreover, our findings contribute to the ongoing research in plasma physics that utilize ion-acoustic wave phenomena. To show the physical behaviour of the solutions, some 3D plots and their respective contour level are shown, choosing different values of the parameters.

Direct measurement of nonlocal quantum states without approximation

Abstract Efficient acquiring information from a quantum state is important for research in fundamental quantum physics and quantum information applications. Instead of using standard quantum state tomography method with reconstruction algorithm, weak value was proposed to directly measure density matrix elements of quantum state. Recently, similar to the concept of weak value, modular values was introduced to extend the direct measurement scheme to nonlocal quantum wave function. However, this method still involves approximation, which leads to inherent low-precision. Here, we propose a new scheme which enables direct measurement for ideal value of the nonlocal density matrix element without taking approximations. Our scheme allows more accurate characterization of nonlocal quantum states, and therefore has greater advantages in practical measurement scenarios.

News From the Foundation for Physical Therapy Research, September 2023.

News From the Foundation for Physical Therapy Research, September 2023.

Characterizing current noise of commercial constant-current sources by using an optically pumped rubidium atomic magnetometer.

This paper introduces a method for characterizing the current noise of commercial constant-current sources (CCSs) using a free-induction-decay (FID) type optically pumped rubidium atomic magnetometer driven by a radio frequency magnetic field. We convert the sensitivity of the atomic magnetometer into the current noise of CCS by calibrating the coil constant. At the same time, the current noise characteristics of six typical commercial low-noise CCSs are compared. The current noise level of the Keysight model B2961A is the lowest among the six tested CCSs, which is 36.233 ± 0.022 nA/Hz1/2 at 1-25Hz and 133.905 ± 0.080 nA/Hz1/2 at 1-100Hz. The sensitivity of the atomic magnetometer is dependent on the current noise level of the CCS. The CCS with low noise is of great significance for high-sensitivity atomic magnetometers. This research provides an important reference for promoting the development of high precision CCS, metrology, and basic physics research.

A deep learning approach for automated segmentation of magnetic bright points in the solar photosphere

Context. Magnetic bright points (MBPs) are small, bright, and conspicuous magnetic structures observed in the solar photosphere and are widely recognized as tracers of magnetic flux tubes. Previous studies have underscored the significance of MBPs in elucidating the mechanisms of coronal heating. The continuous advancement of solar telescopes and observation techniques has significantly enhanced the resolution of solar images, enabling a more detailed examination of MBP structures. In light of the growing availability of MBP observation images, the implementation of large-scale automated and precise MBP segmentation methods holds tremendous potential to facilitate significant progress in solar physics research. Aims. The objective of this study is to propose a deep learning network called MBP-TransCNN that enables the automatic and precise pixel-level segmentation of MBPs in large quantities, even with limited annotated data. This network is designed to effectively handle MBPs of various shapes and backgrounds, including those with complex features. Methods. First, we normalized our sample of MBP images. We then followed this with elastic deformation and rotation translation to enhance the images and expand the dataset. Next, a dual-branch encoder was used to extract the features of the MBPs, and a Transformer-based global attention mechanism was used to extract global contextual information, while a convolutional neural network (CNN) was used to extract detailed local information. Afterwards, an edge aware module was proposed to extract detailed edge features of MBPs, which were used to optimize the segmentation results. Focal loss was used during the training process to address the problem of the small number of MBP samples. Results. The average values of precision, recall, F1, pixel accuracy, and intersection over union of the MBP-TransCNN are 0.976, 0.827, 0.893, 0.999, and 0.808, respectively. Experimental results show that the proposed MBP-TransCNN deep learning network can quickly and accurately segment the fine structure of MBPs.