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This paper employs network theory, mining data and bibliometric analysis when mapping the scientific contribution of Nobel Prize candidate; Manuel Sandoval Vallarta, the first and most renowned Mexican physicist and important figure in Latin American science. Vallarta died in 1977, and the existing literature is about his life and contributions to science but not about how those are still valuable today. This paper is the first to highlight, with mapping tools, that his contributions are relevant to the international community of cosmic rays (as he was pioneer and leader), quantum mechanics and relativity. These tools delivered three findings: Identify how he built his own field of study, same as universal knowledge. Unveil that the backward and forward Vallarta citations follow a scale-free network distribution. Determine social factors that benefited or affected his scientific activities—such as World War II interrupting Vallarta's successful productivity at Massachusetts Institute of Technology. Furthermore, this study confirmed the interdisciplinary nature of the mapping studies of the scientist's contributions using scientometric tools. As a result, several interesting questions arose throughout our research, some of which were answered from the history and philosophy of science. However, others need to be analyzed by experts in the fields of Vallarta. Mapping research sends an invitation to interdisciplinary dialogue/research between experts in different areas of study to better understand the process of knowledge production both, individual and collective. [ABSTRACT FROM AUTHOR]

The 2019 WACEM and academic college of emergency experts india position paper on developing the academic department of space medicine in India - The time has come! The Prime Minister of India in August 2019 announced that India will send astronauts into the space by 2022 in its indigenous spacecraft "Gaganyaan" and also that India will have its own Space Station by 2030.[[1]],[[2]] Ever since Indian Space Research Organization (ISRO) built its first satellite Aryabhatta in 1975, ISRO has come a long way and has successfully sent Chandrayaan-1 and Mangalyaan to the Lunar and Mars orbits, respectively. Success of India's human mission in the space depends heavily on a legitimate SM research powered by an Academic Department of SM. [Extracted from the article]

• Machine learning (ML) techniques were pioneered to analyze non-linear relationships. • Algorithm's predictive power validated ML models, preventing spurious relations. • Recursive feature elimination explored predictor importance. • Presence of non-linear relationships is suggested, advising further investigation. • Acknowledgment of skepticism stresses rigorous analysis for long-term correlations. The Earth's climate is a complex system that can be influenced by various internal and external factors. Previous research has explored the relationship between climate and external forcings such as solar activity and GCR. However, the relations are intricate and intertwined into almost chaotic meteorological measurements. This paper delves deeper into understanding their interactions. GCR flux, Sunspot number (SSN), total solar irradiance (TSI), UV irradiance (UVI), and the Oceanic Niño Index (ONI) are the predictor variables, while total cloud amount (TCA) and low cloud amount (LCA) are the response variables. The analysis begins with standard statistical techniques and continues with multiple regression models including random forest, which is a machine learning (ML) method that can be used for non-linear regression. Subsequently, Recursive Feature Elimination (RFE) is employed to scrutinize the correlation among the predictor parameters. In the ML model, the final 25% of the dataset is held out and tested for validation, so, the predictive power of the algorithm is measured. Both geographical and temporal patterns have been investigated. This study suggests that a non-linear relationship might exist between the parameters, and should be investigated further, particularly in specific regions of the world. [ABSTRACT FROM AUTHOR]

The Spin Physics Detector is an experiment at NICA designed to study the spin structure of the proton and deuteron and the other spin-related phenomena using polarized beams. The collision energy is up to 27 GeV and the luminosity is up to 10 cm s in pp mode. Two scintillator-based detectors, Beam–Beam Counters (BBC), will be installed upstream and downstream the interaction point and will serve as a tool for beam diagnostics including local polarimetry. In this paper, we present the design of the BBC prototype based on the tiles with green WLS and SensL SiPM readout. FERS-5200 is used as the front-end readout system. The amplitude and timing resolutions for different tiles using radioactive source and cosmic rays are obtained. [ABSTRACT FROM AUTHOR]

Space weathering is a primary factor in altering the composition and spectral characteristics of surface materials on airless planets. However, current research on space weathering focuses mainly on the Moon and certain types of asteroids. In particular, the impacts of meteoroids and micrometeoroids, radiation from solar wind/solar flares/cosmic rays, and thermal fatigue due to temperature variations are being studied. Space weathering produces various transformation products such as melted glass, amorphous layers, iron particles, vesicles, and solar wind water. These in turn lead to soil maturation, changes in visible and near-infrared reflectance spectra (weakening of characteristic absorption peaks, decreased reflectance, increased near-infrared slope), and alterations in magnetism (related to small iron particles), collectively termed the "lunar model" of space weathering transformation. Compared to the Moon and asteroids, Mercury has unique spatial environmental characteristics, including more intense meteoroid impacts and solar thermal radiation, as well as a weaker particle radiation environment due to the global distribution of its magnetic field. Therefore, the lunar model of space weathering may not apply to Mercury. Previous studies have extensively explored the effects of micrometeoroid impacts. Hence, this work focuses on the effects of solar-wind particle radiation in global magnetic-field distribution and on the weathering transformation of surface materials on Mercury under prolonged intense solar irradiation. Through the utilization of high-valence state, heavy ion implantation, and vacuum heating simulation experiments, this paper primarily investigates the weathering transformation characteristics of the major mineral components such as anorthite, pyroxene, and olivine on Mercury's surface and compares them to the weathering transformation model of the Moon. The experimental results indicate that ion implantation at room temperature is insufficient to generate np-Fe0 directly but can facilitate its formation, while prolonged exposure to solar thermal radiation on Mercury's surface can lead directly to the formation of np-Fe0. Therefore, intense solar thermal radiation is a crucial component of the unique space weathering transformation process on Mercury's surface. [ABSTRACT FROM AUTHOR]

In the absence of supplementary heat, the radiative cooling of halo gas around massive galaxies (Milky Way mass and above) leads to an excess of cold gas or stars beyond observed levels. Active galactic nucleus jet-induced heating is likely essential, but the specific properties of the jets remain unclear. Our previous work concludes from simulations of a halo with |$10^{14} \,\mathrm{ M}_\odot$| that a successful jet model should have an energy flux comparable to the free-fall energy flux at the cooling radius and should inflate a sufficiently wide cocoon with a long enough cooling time. In this paper, we investigate three jet modes with constant fluxes satisfying the criteria, including high-temperature thermal jets, cosmic ray (CR)-dominant jets, and widely precessing kinetic jets in |$10^{12}-10^{15}\, {\rm M}_{\odot }$| haloes using high-resolution, non-cosmological magnetohydrodynamic simulations with the FIRE-2 (Feedback In Realistic Environments) stellar feedback model, conduction, and viscosity. We find that scaling the jet energy according to the free-fall energy at the cooling radius can successfully suppress the cooling flows and quench galaxies without violating observational constraints. On the contrary, if we scale the energy flux based on the total cooling rate within the cooling radius, strong interstellar medium cooling dominates this scaling, resulting in a jet flux exceeding what is needed. Among the three jet types, the CR-dominant jet is most effective in suppressing cooling flows across all surveyed halo masses due to enhanced CR pressure support. We confirm that the criteria for a successful jet model work across a wider range, encompassing halo masses of |$10^{12}-10^{15} {\rm M_\odot }$|⁠. [ABSTRACT FROM AUTHOR]

Low fluxes of astrophysical neutrinos at TeV energies, and the overwhelming background of atmospheric neutrinos below that, render the current paradigm of neutrino astronomy a severely statistics-limited one. While many hints have emerged, all the evidence gathered by IceCube and ANTARES, over the course of almost a decade and a half of operation, has fallen short of providing any conclusive answer to the puzzle of the origin of high-energy cosmic rays and neutrinos. The advancement of the field is thus closely associated with not only the neutrino observatories coming online in the next few years, but also on the coordinated efforts of the EM, GW and cosmic ray communities to develop dedicated channels and infrastructure that allow for the swift and comprehensive multi-messenger follow-up of relevant events detected in any of these sectors. This paper highlights the strides that have been already taken in that direction and the fruits that they have borne, as well as the challenges that lie ahead. [ABSTRACT FROM AUTHOR]

Since Pauli's hypothesis of their existence in 1930, neutrinos never ceased to bring into play novel ideas and to add new pieces of physics in the whole picture of fundamental interactions. They are only weakly interacting and, at odds with Standard Model's predictions, have a mass less than one millionth of the electron mass, which makes the investigation of their properties very challenging. The issue of the measurement of neutrino's rest mass gained a wider and wider consensus since its discovery through neutrino oscillations in 1998. Various neutrino sources are available for experiments, ranging from nuclear collisions of cosmic rays in the Earth atmosphere and supernova explosions to neutrino beams produced by accelerators and power reactors. These suggest different approaches to the experimental detection and measurement of the absolute value of the neutrino mass. In this paper, we retrace the intriguing story of this endeavor, focusing mainly on direct mass determination methods. The puzzling issue of the nature of massive neutrinos is addressed as well with explicit reference to the phenomenon of double beta-decay as a viable experimental tool to discriminate between Dirac's and Majorana's nature. [ABSTRACT FROM AUTHOR]

The upcoming Nancy Grace Roman Space Telescope will carry out a wide-area survey in the near-infrared. A key science objective is the measurement of cosmic structure via weak gravitational lensing. Roman data will be undersampled, which introduces new challenges in the measurement of source galaxy shapes; a potential solution is to use linear algebra-based coaddition techniques such as imcom that combine multiple undersampled images to produce a single oversampled output mosaic with a desired 'target' point spread function (PSF). We present here an initial application of imcom to 0.64 square degrees of simulated Roman data, based on the Roman branch of the Legacy Survey of Space and Time (LSST) Dark Energy Science Collaboration (DESC) Data Challenge 2 (DC2) simulation. We show that imcom runs successfully on simulated data that includes features such as plate scale distortions, chip gaps, detector defects, and cosmic ray masks. We simultaneously propagate grids of injected sources and simulated noise fields as well as the full simulation. We quantify the residual deviations of the PSF from the target (the 'leakage'), as well as noise properties of the output images; we discuss how the overall tiling pattern as well as Moiré patterns appear in the final leakage and noise maps. We include appendices on interpolation algorithms and the interaction of undersampling with image processing operations that may be of broader applicability. The companion paper ('Paper II') explores the implications for weak lensing analyses. [ABSTRACT FROM AUTHOR]

Focused Very-High Energy Electron (VHEE, 50–300 MeV) and Ultra-High Energy Electron (UHEE, > 300 MeV) beams can accurately target both large and deeply seated human tumors with high sparing properties, while avoiding the spatial requirements and cost of proton and heavy ion facilities. Advanced testing phases are underway at the CLEAR facilities at CERN (Switzerland), NLCTA at Stanford (USA), and SPARC at INFN (Italy), aiming to accelerate the transition to clinical application. Currently, Monte Carlo (MC) transport is the sole paradigm supporting preclinical trials and imminent clinical deployment. In this paper, we propose an alternative: the first extension of the nuclear-reactor deterministic chain Njoy-Dragon for VHEE and UHEE applications. We have extended the Boltzmann-Fokker-Planck (BFP) multigroup formalism and validated it using standard radio-oncology benchmarks, complex assemblies with a wide range of atomic numbers, and comprehensive irradiation of the entire periodic table. We report that 99 % of water voxels exhibit a BFP-MC deviation below 2 % for electron energies under 1.5 GeV . Additionally, we demonstrate that at least 97 % of voxels of bone, lung, adipose tissue, muscle, soft tissue, tumor, steel, and aluminum meet the same criterion between 50 MeV and 1.5 GeV . For water, the thorax, and the breast intra-operative benchmark, typical average BFP-MC deviations of 0.3 % and 0.4 % were observed at 300 MeV and 1 GeV , respectively. By irradiating the entire periodic table, we observed similar performance between lithium ( Z = 3 ) and cerium ( Z = 58 ). Deficiencies observed between praseodymium ( Z = 59 ) and einsteinium ( Z = 99 ) have been reported, analyzed, and quantified, offering critical insights for the ongoing development of the Evaluated Nuclear Data File mode in Njoy. [ABSTRACT FROM AUTHOR]

Large-scale cosmic filaments connect galaxies, clusters, and voids. They are permeated by magnetic fields with a variety of topologies. Cosmic rays with energies up to 10 20 eV can be produced in astrophysical environments associated with star-formation and AGN activities. The fate of these cosmic rays in filaments, which cannot be directly observed on Earth, are rarely studied. We investigate the high-energy processes associated with energetic particles (cosmic rays) in filaments, adopting an ecological approach that includes galaxies, clusters/superclusters, and voids as key cosmological structures in the filament ecosystem. We derive the phenomenology for modelling interfaces between filaments and these structures, and investigate how the transfer and fate of energetic cosmic ray protons are affected by the magnetism of the interfaces. We consider different magnetic field configurations in filaments and assess the implications for cosmic ray confinement and survival against hadronic pion-producing and photo-pair interactions. Our analysis shows that the fate of the particles depends on the location of their origin within a filament ecosystem, and that filaments act as 'highways', channelling cosmic rays between galaxies, galaxy clusters, and superclusters. Filaments can also operate as cosmic 'fly paper', capturing cosmic ray protons with energies up to 10 18 eV from cosmic voids. Our analysis predicts the presence of a population of ∼ 10 12 – 10 16 eV cosmic ray protons in filaments and voids accumulated continually over cosmic time. These protons do not suffer significant energy losses through photo-pair or pion production, nor can they be cooled efficiently. Instead, they form a cosmic ray fossil record of the power generation history of the Universe. [ABSTRACT FROM AUTHOR]

The LiteBIRD experiment is an international spaceborne mission, led by JAXA, the Japan Aerospace Exploration Agency, to observe cosmic microwave background (CMB) radiation. The satellite will be deployed to measure and characterize the signature of the primordial gravitational waves from cosmic inflation in the B-mode polarization of the CMB radiation. LiteBIRD will also explore the nature of quantum gravity as well as attempt to detect the recombination peak and reionization peak with greater than 5σ significance for a tensor-to-scalar value of r = 0.01. These observations and measurements will take place over 15 separate frequency bands in the range of 34–448 GHz. The 15 frequency channels are separated into three telescopes—low, medium, and high frequency. This paper will describe the process flow developed to fabricate the low frequency detectors, covering bands from 34 to 161 GHz. The detector wafer itself has a device side and a sky side. The device side contains the trichroic polarization sensitive sinuous antennae coupled to transition-edge sensor detectors. The skyside contains the cosmic ray mitigation structure. [ABSTRACT FROM AUTHOR]

The static random-access memory (SRAM) physical unclonable function (PUF) uses the power-up states of stored values to derive the identification code. Its lightweight circuit design makes it suitable for power-sensitive satellites. However, the SRAM PUF is significantly affected by high-energy particles and cosmic rays in space, which causes incorrect output of identity authentication codes and further leading to a degradation in reliability. Recently, the main research works are concerned about the impact of cosmic rays induced total ionizing dose effects on the SRAM PUF, and few reports discuss the high-energy particles induced single event effects on the SRAM PUF. This paper presents the reliability results of planar and FinFET-based SRAM PUFs after high-energy heavy ion experiments. Experimental results indicate that 3%–10% of the SRAM PUF bits change from their original power-on states, which demonstrate that ion-induced microdose effects degrade the reliability of SRAM PUFs. In addition, the three-dimensional technology computer-aided design simulation tool is used to analyze the physical mechanisms of the experimental phenomena. Simulation results show that the heavy ion-induced microdose effect ionizes and produces trapped charges at the silicon/insulation interface, which causes a slight change in transistor leakage current or a slight drift in threshold voltage. The physical mechanisms lead to an off-state current mismatch in the SRAM cell and finally affect the stored values after power-on. [ABSTRACT FROM AUTHOR]

Electron densities in different locations of our galaxy are obtained in pulsar astronomy by dividing the dispersion measure (DM) by the distance of the pulsar to Earth. The properties of the interstellar plasma are related to its heating by cosmic rays. Following the present analysis, DM's measurements are obtained with different properties of the corresponding plasmas at different temperatures. (1) For relatively low temperatures (around and below 10,000 (K)), the state of molecular, atomic and ionized hydrogen is analyzed by the interstellar medium model with partially ionized plasma. In this region, various spectroscopic effects are obtained. (2) For temperatures above this limit, the interstellar gas is found to be a completely ionized medium, and this plasma is defined as warm ionized medium (WIM) plasma. We show in the first part of the paper that this plasma is transparent, as obtained from the solution of Saha's equation. The index of refraction of the WIM plasma is real, but the plasma can be observed by dispersion measurements. (3) For very high temperatures (around 1 million (K)), the plasma is defined as hot ionized medium, where X-rays are obtained. We concentrate in the present work on the analysis of WIM plasma. We calculate the mass densities of this plasma and compare it with dark matter mass densities, which are found to be larger. But some factors which may reduce this difference are discussed. [ABSTRACT FROM AUTHOR]

Muography is a rapidly developing and non-destructive tomographic technology that uses cosmic ray muons. Due to the natural presence and deeper penetration of cosmic ray muons, scientists have performed various pioneer studies in fields, such as customs security, the internal imaging of volcanoes, scientific archaeology, and others. With unique advantages, muography has gained increasing attention from archaeologists as a novel and innovative tool to investigate large-scale archaeological sites. This approach may be especially helpful for identifying endangered cultural relics and monuments. In the work, we employ a compact, rugged, and portable muon imaging system, CORMIS (COsmic Ray Muon Imaging System), deployed at up to six measurement locations to perform a case study of three-dimensional muography in Xi'an city, China. Cultural cities, such as Xi'an, have long histories and could benefit from innovative techniques used to investigate, conserve, and protect large historical sites. In this paper, we present in detail a high resolution survey on a rampart of a Xi'an defensive wall in demand of urgent protection. The survey data are carefully processed with advanced statistical methods newly introduced in muography, and the results indicate density anomalies inside the rampart with unprecedented levels of precision. The density anomalies are potential safety hazards and need to be eliminated as soon as possible. The successful implementation of this survey significantly encourages more engagement on the tangible application of high-precision 3D muography in archaeological investigations and protection projects around the world. [ABSTRACT FROM AUTHOR]

This article explores the overlooked history of atmospheric electricity in the last third of the nineteenth century, delineating the work of Austrian physicist Franz Exner and German schoolteachers Julius Elster and Hans Geitel, and identifying the consequences of their work for twentieth-century physics. Since the earliest days of electrical science, the constant electrification of the atmosphere had been a persistent puzzle, with histories by historians and physicists alike typically focusing on what came after the discovery of gaseous ions in the atmosphere in 1899: cosmic rays, radioactivity, particle physics, and quantum phenomena. I argue that Exner and Elster and Geitel's creative work in atmospheric electricity before 1899 provided the essential conditions for these twentieth-century discoveries. Their divergent theories, experiments, instruments, and environments, developed to understand the origins of the atmosphere's electrification, provided a setting for new ideas about charge, determinism, and measurement to arise. This paper expands on the existing scholarship that has pointed to the fruitful interactions between physics and meteorology in British contexts in this period. In disentangling Exner's and Elster and Geitel's differing views on geographical and meteorological conditions I offer a new perspective on the recent vertical turn in the history of science. The paper concludes by suggesting that while the ionic revolution of 1899 was foundational for much of twentieth-century physics, it constituted a significant theoretical undoing for atmospheric electricians, leaving the field with even less understanding of the atmosphere's electrification than before. [ABSTRACT FROM AUTHOR]

The total luminosity and spectral shape of the non-thermal emission produced by cosmic rays depends on their interstellar environment, a dependence that gives rise to correlations between galaxies' bulk properties – star-formation rate, stellar mass, and others – and their non-thermal spectra. Understanding the physical mechanisms of cosmic ray transport, loss, and emission is key to understanding these correlations. Here, in the first paper of the series, we present a new method to compute the non-thermal spectra of star-forming galaxies, and describe an open-source software package – congruents (COsmic ray, Neutrino, Gamma-ray, and Radio Non-Thermal Spectra) – that implements it. As a crucial innovation, our method requires as input only a galaxy's effective radius, star-formation rate, stellar mass, and redshift, all quantities that are readily available for large samples of galaxies and do not require expensive, spatially resolved gas measurements. From these inputs we derive individual, galaxy-by-galaxy models for the background gas and radiation field through which cosmic rays propagate, from which we compute steady-state cosmic ray spectra for hadronic and leptonic particles in both the galactic disc and halo by solving the full kinetic equation. We invoke modern models for cosmic ray transport and include all significant emission and loss mechanisms. In this paper, we describe the model and validate it against non-thermal emission measured in nearby star-forming galaxies that span four orders of magnitude in star-formation rate. [ABSTRACT FROM AUTHOR]

This paper presents the results of an analysis of observations of the Crab Nebula gamma-ray source with the first two atmospheric Cherenkov telescopes of the TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) astrophysical complex in the stereo mode of observations. The article analyzed observational data from 2020 to 2021. Over 36 hours of observations, a signal was obtained at a statistical significance level of 5 and a spectrum of gamma rays was plotted in the energy range from 2 to 70 TeV. The paper describes a technique for gamma–hadron separation and reconstruction of detected gamma-rays energy. [ABSTRACT FROM AUTHOR]

Since the discovery of the cosmic X-ray background (CXB), astronomers have strived to understand the accreting supermassive black holes (SMBHs) contributing to its peak in the 10-40 keV band. Existing soft X-ray telescopes could study this population up to only 10 keV, and, while NuSTAR (focusing on 3-24 keV) made great progress, it also left significant uncertainties in characterizing the hard X-ray population, crucial for calibrating current population synthesis models. This paper presents an in-depth analysis of simulations of two extragalactic surveys (deep and wide) with the High-Energy X-ray Probe (HEX-P), each observed for 2 Ms. Applying established source detection techniques, we show that HEX-P surveys will reach a flux of ~10-15 erg s-1 cm-2 in the 10-40 keV band, an order of magnitude fainter than current NuSTAR surveys. With the large sample of new hard X-ray detected sources (~2000), we showcase HEX-Ps ability to resolve more than 80% of the CXB up to 40 keV into individual sources. The expected precision of HEX-Ps resolved background measurement will allow us to distinguish between population synthesis models of SMBH growth. HEX-P will leverage accurate broadband (0.5-40 keV) spectral analysis and the combination of soft and hard X-ray colors to provide obscuration constraints even for the fainter sources, with the overall objective of measuring the Compton-thick fraction. With unprecedented sensitivity in the 10-40 keV band, HEX-P will explore the hard X-ray emission from AGN to flux limits never reached before, thus expanding the parameter space for serendipitous discoveries. Consequently, it is plausible that new models will be needed to capture the population HEX-P will unveil. [ABSTRACT FROM AUTHOR]

This paper discusses Indonesia's space / aerospace industry program as the nation's future Soft Power. The term 'soft power', coined by Joseph S. Nye of Harvard University in the United States, is the ability of a country to influence another country not through coercive means but through attractiveness or reputation. This research uses a literature research approach, which is a method by collecting data by understanding and studying theories from various literature related to research There are four stages of literature study in research. Space, or simply space, is the expanse that exists beyond the Earth and between celestial bodies. Space isn't completely empty it's a hard vacuum containing low particle densities, especially hydrogen and helium plasma, as well as electromagnetic radiation, magnetic fields, neutrinos, dust, and cosmic rays. Recent developments show that in the future, not only professional astronauts can go into space but also all citizens of the world can afford to pay. [ABSTRACT FROM AUTHOR]

The YangBaJing Hybrid Array (YBJ-HA) is located at the Yangbajing international cosmic ray observatory, Tibet, China. It consists of 115 scintillation detectors (SDs) and 16 underground water Cherenkov muon detectors (MDA). Its main physical goal is to observe the γ -ray sources in the 100 TeV energy region, so the array must have very good pointing accuracy. To achieve this performance, the time response of the scintillator detectors must have high consistency. This paper introduces a characteristic plane method (offline calibration method) to calibrate the time of each scintillator detector and uses the moon shadow analysis results to test the time calibration accuracy. [ABSTRACT FROM AUTHOR]

The charged components of cosmic ray secondary particles are deflected by thunderstorm electric fields as they pass through kilometer-scale thunderclouds. As a result, the information on location of secondary particles reaching the observation level will be affected, and the lateral distribution will also be changed. In this paper, the Monte Carlo method is used to simulate the effects of near-earth thunderstorm electric field on the lateral distribution of secondary particles at LHAASO. A vertical and uniform atmospheric electric field model is used in our simulations. The results show that during thunderstorm the lateral distribution of secondary particles widens, and the variation amplitude is not only associated with the strength of electric field, but also dependent upon the primary energy and zenith angle of cosmic rays. In an electric field of - 1000 V · cm − 1 (below the threshold of the Relatively Runaway Electron Avalanche, RREA), the variation amplitude of the lateral distribution of secondary particles is about 0.7% for θ = 0 ∘ , and the variation amplitude reaches 4.7% for θ = 50 ∘. The primary energy of cosmic rays is about 180 GeV, the increasing amplitude is about 0.6%. When the primary energy is about 560 TeV, the variation can be up to 20.1%. In an electric field of - 1700 V · cm − 1 (above the threshold of the RREA process), the increasing amplitude of the lateral distribution is greater than that in an electric field of - 1000 V · cm − 1. And the variation amplitude is 3.8% for θ = 0 ∘ and 34% for θ = 50 ∘ , respectively. For the primary energy of about 180 GeV, the increasing amplitude of secondary particles is 9.9%. For the primary energy of about 560 TeV, the variation can be as high as 119%. Our simulation results are helpful to understand the deflection mechanisms of cosmic ray secondary particles generated by the near-earth thunderstorm electric field, as well as the variation of LHAASO data during thunderstorms. [ABSTRACT FROM AUTHOR]

In this paper, we constrain the density of the interstellar medium (ISM) around the hadronic PeVatron candidate, supernova remnant (SNR) G106.3+2.7, based on X-ray and γ-ray observations. The purpose of this investigation is to understand the influence of the gaseous environment on this SNR as a proton PeVatron candidate. By modelling the self-regulated propagation of the cosmic rays (CRs) injected from the SNR, we calculate the γ-ray emission of CRs via the hadronuclear interactions with the molecular cloud and the ISM, and use the measured γ-ray flux to constrain the ISM density around the SNR. Our results support the picture that the SNR is expanding into a low-density (⁠|$\lt 0.05\, {\rm cm}^{-3}$|⁠) cavity, enabling the SNR to be a potential proton PeVatron despite that it is presently not in the very early phase. [ABSTRACT FROM AUTHOR]

The development of experimental methods that distinguish between light from objects with a similar color temperature and polarization presents a significant practical problem. In this paper, we demonstrate that the two-point correlation function (and its resultant correlation length) of a black body with an extended angular spectrum significantly differs from that of a black body with a narrow angular one. Using these results, we discuss an interferometric method as a possible experimental tool for discriminating between objects with the same color temperature but having different angular spectra. [ABSTRACT FROM AUTHOR]

The origin of high-energy cosmic rays, and their behavior in astrophysical sources, remains an open question. Recently, new ways to address this question have been made possible by the observation of a new astrophysical messenger, namely neutrinos. The IceCube telescope has detected a diffuse flux of astrophysical neutrinos in the TeV-PeV energy range, likely produced in astrophysical sources accelerating cosmic rays, and more recently it has reported on a few candidate individual neutrino sources. Future experiments will be able to improve on these measurements quantitatively, by the detection of more events, and qualitatively, by extending the measurement into the EeV energy range. In this paper, we review the main features of the neutrino emission and sources observed by IceCube, as well as the main candidate sources that could contribute to the diffuse neutrino flux. As a parallel question, we review the status of high-energy neutrinos as a probe of Beyond the Standard Model physics coupling to the neutrino sector. [ABSTRACT FROM AUTHOR]

Recently, a new population of circular radio (∼GHz) objects has been discovered at high Galactic latitudes, called the odd radio circles (ORCs). A fraction of the ORCs encircles massive galaxies in the sky with stellar mass ∼1011 M⊙ situated at z  = 0.2–0.6, suggesting a possible physical connection. In this paper, we explore the possibility that these radio circles originate from the accretion shocks/virial shocks around massive (⁠|${\gtrsim} 10^{13}\, \ {\rm M}_\odot$|⁠) dark matter halo at z ∼ 0.5. We found that the radio flux density of the emitting shell is marginally consistent with the ORCs. We also find that pure advection of electrons from the shock results in a radio-emitting shell that is considerably narrower than the observed one due to strong inverse-Compton cooling of electrons. Instead, we show that the diffusion of cosmic-ray (CR) electrons plays a significant role in increasing the width of the shell. We infer a diffusion coefficient, |$D_{\rm cr} \sim 10^{30}\ {\rm cm^2\, s^{-1}}$|⁠ , consistent with the values expected for low-density circumgalactic medium (CGM). If ORCs indeed trace virial shocks, then our derived CR diffusion coefficient represents one of the few estimations available for the low-density CGM. Finally, we show that the apparent discrepancy between ORC and halo number density can be mitigated by considering an incomplete halo virialization and the limited radiation efficiency of shocks. This study therefore opens up new avenues to study such shocks and non-thermal particle acceleration within them. Furthermore, our results suggest that low-mass galaxies (≲1013 M⊙) may not show ORCs due to their significantly lower radio surface brightness. [ABSTRACT FROM AUTHOR]

Satellite laser altimetry technology, a novel space remote sensing technique, actively acquires high-precision elevation information about the Earth's surface. However, the accuracy of laser altimetry can be compromised by alterations in the satellite-ground environment, thermal dynamics, and cosmic radiation. These factors may induce subtle variations in the installation and internal structure of the spaceborne laser altimeter on the satellite platform, diminishing measurement precision. In-orbit calibration is thus essential to enhancing the precision of laser altimetry. Through collaborative calculations between satellite and ground stations, we can derive correction parameters for laser pointing and ranging, substantially improving the accuracy of satellite laser altimetry. This paper introduces a sophisticated calibration method for laser altimeter pointing and ranging that utilizes dense control points. The approach interpolates discrete ground control point data into continuous simulated terrain using empirical Bayesian kriging, subsequently categorizing the data for either pointing or ranging calibration according to their respective functions. Following this, a series of calibration experiments are conducted, prioritizing "pointing" followed by "ranging" and continuing until the variation in the ranging calibration results falls below a predefined threshold. We employed experimental data from ground control points (GCPs) in Xinjiang and Inner Mongolia, China, to calibrate the GaoFen-7 (GF-7) satellite Beam 2 laser altimeter as per the outlined method. The calibration outcomes were then benchmarked against those gleaned from infrared laser detector calibration, revealing disparities of 1.12 s in the pointing angle and 2 cm in the ranging correction value. Post validation with ground control points, the measurement accuracy was refined to 0.15 m. The experiments confirm that the proposed calibration method offers accuracy comparable to that of infrared laser detector calibration and can facilitate the updating of 1:10,000 topographic maps utilizing stereo optical imagery. Furthermore, this method is more cost-effective and demands fewer personnel for ground control point collection, enhancing resource efficiency compared to traditional infrared laser detector calibration. The proposed approach surpasses terrain-matching limitations when calibrating laser ranging parameters and presents a viable solution for achieving frequent and high-precision in-orbit calibration of laser altimetry satellites. [ABSTRACT FROM AUTHOR]

Although celestial sources emitting in the few tens of GeV up to a few TeV are being investigated by imaging atmospheric Čerenkov telescope arrays such as H.E.S.S., MAGIC, and VERITAS, at higher energies, up to PeV, more suitable instrumentation is required to detect ultra-high-energy photons, such as extensive air shower arrays, as HAWC, LHAASO, Tibet AS- γ. The Italian National Institute for Astrophysics has recently become the leader of an international project, the ASTRI Mini-Array, with the aim of installing and operating an array of nine dual-mirror Čerenkov telescopes at the Observatorio del Teide in Spain starting in 2025. The ASTRI Mini-Array is expected to span a wide range of energies (1–200 TeV), with a large field of view (about 10 degrees) and an angular and energy resolution of ∼3 arcmin and ∼10 %, respectively. The first four years of operations will be dedicated to the exploitation of Core Science, with a small and selected number of pointings with the goal of addressing some of the fundamental questions on the origin of cosmic rays, cosmology, and fundamental physics, the time-domain astrophysics and non γ -ray studies (e.g., stellar intensity interferometry and direct measurements of cosmic rays). Subsequently, four more years will be dedicated to Observatory Science, open to the scientific community through the submission of observational proposals selected on a competitive basis. In this paper, I will review the Core Science topics and provide examples of possible Observatory Science cases, taking into account the synergies with current and upcoming observational facilities. [ABSTRACT FROM AUTHOR]

LUX-ZEPLIN (LZ) collaboration has achieved the strongest constraint on weak-scale dark matter (DM)-nucleon spin-independent (SI) scattering cross section in a large region of parameter space. In this paper, we take a complementary approach and study the prospect of detecting cosmic-ray boosted sub-GeV DM in LZ. In the absence of a signal for DM, we improve upon the previous constraints by a factor of ∼ 2 using the LZ result for some regions of the parameter space. We also show that upcoming XENONnT and future Darwin experiments will be sensitive to cross sections smaller by factors of ∼ 3 and ∼ 10 compared to the current LZ limit, respectively. [ABSTRACT FROM AUTHOR]

This paper presents the results of the sky survey with the TAIGA–HiSCORE installation, an array of 120 wide-angle Cherenkov light detectors spread over an area of 1 km2. Data analysis is made for 2 winter seasons (2019–2021) at cosmic ray energies above 200–500 TeV. A modified method of background estimation is tested. Signal significance is estimated using classical Li-Ma method. [ABSTRACT FROM AUTHOR]

Beryllium, the 44th most abundant element in the Earth's crust, is found ubiquitously in environmental matrices, including air, soil, and water, as well as in a variety of food items such as grains, fruits, and vegetables. The typical concentration of Be in air is reported to be ~0.05 ng/m3, whereas in soil, its concentration varies from ~2 to 5 ppm. The prevalence of Be in soil leads to its presence in water as well as in plants, and various human activities such as burning of coal, petrol, diesel, mining, and other industrial activities may further increase the concentration of beryllium in environment and associated matrices. It needs to be mentioned that the typical concentration of Be in food items is of the order of few ppb, whereas in drinking water, the typical values are reported to be <1 ppb or so. Based on the literature survey including some of the most recent studies, the present paper provides summary on concentration of Be in air, soil, and other relevant matrices as concise and consolidated reports on beryllium are scarce. In addition, related information like Be in drinking water along with available guidelines is also provided. Information on the prevalence of other isotopes of beryllium, i.e., 7Be4 and 10Be4, which are radioactive and are produced by cosmic rays in atmosphere, is also included in the present paper. [ABSTRACT FROM AUTHOR]

For the purpose of detecting gravitational waves from space, high-energy particles will infiltrate the satellite's structure and accumulate charges on the test mass, consequently diminishing detection performance. Present investigations into the charging rate of the test mass typically rely on the particle distribution of Earth orbit. However, the influence of the Earth's magnetosphere needs to be considered for the Tianqin detector because of its geocentric orbit. In this paper, artificial neural network is used to fuse satellite data and the galactic cosmic rays model to give the distribution of high-energy particles in the Tianqin orbit. And then, the charging rate is estimated by Monte Carlo simulation. The simulation results show that the flux of hundreds of MeV particles is a little higher than that in Earth orbit, which lead to 3 − 4 e s−1 higher than LISA, i.e. the charging rate of approximately 43 e s−1 during periods of solar minimum and 19 e s−1 during periods of solar maximum. These findings hold substantial implications for guiding the design of the charge management system. [ABSTRACT FROM AUTHOR]

The origin, acceleration, and propagation of high-energy cosmic rays is one of the most important questions in modern physics and astronomy. To fully uncover such a mystery, precise measurements of the energy spectra and anisotropies of cosmic rays, as well as multi-wavelength electromagnetic radiation from various types of energetic objects are required. The direct measurements of energy spectra of different species via particle detectors in space are an essential way to study cosmic ray physics. China launched the first space astronomical satellite, the Dark Matter Particle Explorer (DAMPE) in the end of 2015, which keeps operation in space for more than 7 years. The DAMPE has a relatively large acceptance and a high energy resolution, and has made important progresses in measuring the spectral structures of cosmic ray protons, helium nuclei, and boron-to-carbon and boron-to-oxygen ratios. These new measurements bring new insights in understanding the origin and propagation of cosmic rays. This paper reviews the instrumentation and operation of DAMPE, with an emphasis on its scientific results and physical implications in cosmic ray studies. [ABSTRACT FROM AUTHOR]

In this paper we report the detection of five strong gamma-ray bursts (GRBs) by the High-Energy Particle Detector (HEPD-01) mounted on board the China Seismo-Electromagnetic Satellite, operational since 2018 on a Sun-synchronous polar orbit at a ∼507 km altitude and 97° inclination. HEPD-01 was designed to detect high-energy electrons in the energy range 3–100 MeV, protons in the range 30–300 MeV, and light nuclei in the range 30–300 MeV n−1. Nonetheless, Monte Carlo simulations have shown HEPD-01 is sensitive to gamma-ray photons in the energy range 300 keV–50 MeV, even if with a moderate effective area above ∼5 MeV. A dedicated time correlation analysis between GRBs reported in literature and signals from a set of HEPD-01 trigger configuration masks has confirmed the anticipated detector sensitivity to high-energy photons. A comparison between the simultaneous time profiles of HEPD-01 electron fluxes and photons from GRB190114C, GRB190305A, GRB190928A, GRB200826B, and GRB211211A has shown a remarkable similarity, in spite of the different energy ranges. The high-energy response, with peak sensitivity at about 2 MeV, and moderate effective area of the detector in the actual flight configuration explain why these five GRBs, characterized by a fluence above ∼3 × 10−5 erg cm−2 in the energy interval 300 keV–50 MeV, have been detected. [ABSTRACT FROM AUTHOR]

A fundamental problem in space plasma physics and astrophysics is to understand the behaviour of magnetic field lines in turbulence. In the past it was controversial what aspects of turbulence are most important in field line random walk theory. In the current paper we employ numerical tools, commonly referred to as simulations, to gain more insight. In particular, we explore the importance of the energy range of the turbulence spectrum, spectral anisotropy, as well the existence of a component of the turbulent magnetic field parallel with respect to the mean magnetic field. The latter point is directly related to the question whether field line random walk in compressible turbulence behaves differently compared to random walk in incompressible turbulence. [ABSTRACT FROM AUTHOR]

In this paper we study the statistical relations between geomagnetic indices and the characteristics of cosmic rays and interplanetary disturbances for Forbush decreases associated with (a) coronal mass ejections from active regions accompanied by solar flares, (b) filament eruptions outside active regions, (c) high-speed streams from coronal holes, and (d) multiple sources. For sporadic Forbush decreases, the dependence of geomagnetic indices on cosmic ray and solar wind parameters in the presence or absence of a magnetic cloud is compared using statistical methods. The results show that (a) the highest geoeffectiveness is characteristic of interplanetary disturbances associated with solar matter eruptions from active regions in the presence of a magnetic cloud (and the lowest one for recurrent disturbances), (b) sporadic and recurrent events differ not only in the magnitude of geomagnetic indices and the southern component of the magnetic field but also in the nature of the relationship between them, (c) the geoeffectiveness of transient solar wind disturbances depends more strongly on the presence or absence of a magnetic cloud than on the type of solar source, and (d) for interplanetary disturbances associated with filament eruptions outside active regions, in the presence of a magnetic cloud, the geoeffectiveness depends only on the southern component of the magnetic field, while for other types of disturbances it depends on other solar wind parameters. [ABSTRACT FROM AUTHOR]

The observed variations in intense geomagnetic flux lobes have a significant impact on regional geomagnetic fields, and produce unique geomagnetic characteristics. To investigate the time‐dependent effect of the Siberian flux lobe on the geomagnetic field in East Asia, we reconstructed a stacked full‐vector paleomagnetic secular variation record (since 2000 BCE) from three sediment cores collected in the Bohai Sea, China. Age models of the studied cores were established through a combination of radiocarbon 14C dating and inter‐profile correlation of mass‐normalized magnetic susceptibility. Rock magnetic results indicate that fine‐grained magnetite is the primary remanent carrier. We found that the paleomagnetic field records in the Bohai Sea correspond more closely with those from the middle latitudes, rather than the low latitudes. This was primarily attributed to the variation of the Siberian flux lobe. This study provides a better understanding of the contrasting patterns of regional geomagnetic fields in East Asia, and emphasizes the significant role played by the Siberian flux intensity lobe in shaping their formation. Plain Language Summary: The Earth's magnetic field is in a constant state of flux, both temporally and spatially, and plays a crucial role in protecting our planet from solar wind and cosmic rays. The long‐term variation of the Earth's magnetic field is closely linked with the magnetic flux patch situated at the core‐mantle boundary. However, our understanding of the evolution of magnetic flux patches has been limited by the use of short‐term instrumental data and discrete archeomagnetic data. In this paper, we reconstruct a ∼4,000‐year high‐resolution full‐vector paleomagnetic record from sediments in the Bohai Sea, China. Our findings reveal a clear contrast in the paleomagnetic variations between the middle and low latitudes of East Asia. We proposed that the Siberian flux intensity lobe likely played an important role in the observed paleomagnetic behavior discrepancy between the low‐ and mid‐latitudes of East Asia. Key Points: A multi‐decadal resolution paleomagnetic record spanning approximately 4,000 years has been derived from sediments in the Bohai Sea, ChinaThe paleomagnetic behavior differs between middle and low latitudes across East Asia, indicating the variation of the Siberian flux lobeThe disparity in inclination between the Chinese and Levantine spikes implies that these spikes arise from separate magnetic flux patches [ABSTRACT FROM AUTHOR]

Pix.PAN is a compact cylindrical magnetic spectrometer, intended to provide excellent high energy particle measurements under high rate and hostile operating conditions in space. Its principal design is composed of two Halbach-array magnetic sectors and six Timepix4-based tracking layers; the latest hybrid silicon pixel detector readout ASIC designed. Due to Pix.PAN's compact and relatively simple design, it has the potential to be used for space missions exploring with measurements of unprecedented precision, high energy particles in radiation belts and the heliophere (solar energetic particles, anomalous and galactic cosmic rays). In this white paper, we discuss the design and expected performance of Pix.PAN for COMPASS (Comprehensive Observations of Magnetospheric Particle Acceleration, Sources, and Sinks), a mission concept submitted to NASA's Call "B.16 Heliophysics Mission Concept Studies (HMCS)" in 2021 that targets the extreme high energy particle environment of Jupiter's inner radiation belts. We also discuss PixPAN's operational conditions and interface requirements. The conceptual design shows that is possible to achieve an energy resolution of<12% for electrons in the range of 10 MeV-1 GeV and<35% for protons between ∼ 200 MeV to a few GeV. Due to the timestamp precision of Timepix4, a time resolution (on an instrument level) of about 100 ps can be achieved for time-of-flight measurements. In the most intense radiation environments of the COMPASS mission, Pix.PAN is expected to have a maximum hit rate of 44 MHz cm 2 which is below the design limit of 360 MHz cm 2 of Timepix4. Finally, a sensor design is proposed which allows the instrument to operate with a power budget of 20W without the loss of scientific performance. [ABSTRACT FROM AUTHOR]

Interstellar dust (ISD) particles penetrate the solar system due to the relative motion of the Sun and the local interstellar cloud. Before entering the heliosphere, they pass through the heliospheric interface – the region of the solar wind interaction with the interstellar plasma. The size distribution and number density of dust grains are modified in the interface essentially. The modification depends on the charging of the dust particles along their trajectories. In this paper, we present modeling results of the charging of ISD particles passing through the heliospheric interface. The main physical processes responsible for the charging within the heliospheric conditions are the sticking of primary plasma particles, secondary electron emission, photoemission, and the effects of cosmic ray electrons. We consider two methods to calculate the electric charge of ISD particles based on (1) the classic steady-state assumption that the charge depends only on local plasma and radiation conditions and (2) the dynamical computation of charge along the particle trajectory. We demonstrate that the steady-state assumption is quite justified to model trajectories and number density distributions of relatively big ISD grains (radius of 100 nm and larger) penetrating the heliosphere. The estimates show that ISD grains of these sizes require less than 0.25 years (distance of ≈ 1 au) after transition from the LISM into the heliosphere to reach an equilibrium. For small particles (radius of 10 nm), the dynamical computation of charge influences the trajectories and modifies the number density substantially. The dust density accumulations are distributed within a more elongated region along the heliopause in case of dynamically changed charge as compared with the use of a steady-state charge approximation. As a result, the magnitudes of number density at the points of density features differ several times between the results obtained by the two considered approaches. [ABSTRACT FROM AUTHOR]

De-excitation gamma-ray lines, produced by nuclei colliding with protons, provide information about astrophysical environments where particles have kinetic energies of 10–100 MeV per nucleon. In general, such environments can be categorized into two types: the interaction between non-thermal MeV cosmic rays and ambient gas, and the other is thermal plasma with a temperature above a few MeV. In this paper, we focus on the latter type and investigate the production of de-excitation gamma-ray lines in very hot thermal plasma, especially the dependence of the line profile on the plasma temperature. We have calculated the line profile of prompt gamma rays from 12C and 16O and found that when nuclei have a higher temperature than protons, gamma-ray line profiles can have a complex shape unique to each nucleus species. This is caused by anisotropic gamma-ray emission in the nucleus rest frame. We propose that the spectroscopy of nuclear de-excitation gamma-ray lines may enable to probe energy distribution in very hot astrophysical plasmas. This diagnostics can be a new and powerful technique to investigate the physical state of a two-temperature accretion flows onto a black hole, especially the energy distributions of the protons and nuclei, which are difficult to access for any other diagnostics. [ABSTRACT FROM AUTHOR]

Identifying the accelerators of Galactic cosmic ray (CR) protons with energies up to a few PeV (1015 eV) remains a theoretical and observational challenge. Supernova remnants (SNRs) represent strong candidates because they provide sufficient energetics to reproduce the CR flux observed at Earth. However, it remains unclear whether they can accelerate particles to PeV energies, particularly after the very early stages of their evolution. This uncertainty has prompted searches for other source classes and necessitates comprehensive theoretical modeling of the maximum proton energy, E max , accelerated by an arbitrary shock. While analytic estimates of E max have been put forward in the literature, they do not fully account for the complex interplay between particle acceleration, magnetic field amplification, and shock evolution. This paper uses a multizone, semianalytic model of particle acceleration based on kinetic simulations to place constraints on E max for a wide range of astrophysical shocks. In particular, we develop relationships between E max , shock velocity, size, and ambient medium. We find that SNRs can only accelerate PeV particles under a select set of circumstances, namely, if the shock velocity exceeds ∼104 km s−1 and escaping particles drive magnetic field amplification. However, older and slower SNRs may still produce observational signatures of PeV particles due to populations accelerated when the shock was younger. Our results serve as a reference for modelers seeking to quickly produce a self-consistent estimate of the maximum energy accelerated by an arbitrary astrophysical shock. 11 Presented as a thesis to the Department of Astronomy and Astrophysics, The University of Chicago, in partial fulfillment of the requirements for a Ph.D. degree. [ABSTRACT FROM AUTHOR]

Active galactic nuclei (AGNs) are widely believed to be one of the promising acceleration sites of ultrahigh-energy cosmic rays (CRs). Essentially, AGNs are powered by the gravitational energy of matter falling into supermassive black holes. However, the conversion efficiency of gravitational to kinetic energy of CRs in AGNs, which is defined as the baryon loading factor η p , is not well known yet. After being accelerated, high-energy CRs could escape the host galaxy and enter the intracluster medium (ICM). These CRs can be confined within the galaxy cluster and produce γ -rays and neutrinos through proton–proton collisions with the ICM. In this paper, we study the diffusion of CRs in galaxy clusters and calculate the diffuse neutrino flux from the galaxy cluster population. Using the latest upper limits on the cumulative unresolved TeV–PeV neutrino flux from galaxy clusters posed by the IceCube Neutrino Observatory, we derive the upper limit of the average baryon loading factor as η p,grav ≲ 2 × 10−3 − 0.1 for the population of galaxy clusters. This constraint is more stringent than the one obtained from γ -ray observation on the Coma cluster. [ABSTRACT FROM AUTHOR]

The paper discusses an approach that made it possible to estimate the distance to the nearest pevatrons, which form a knee in the spectrum of the cosmic ray nucleon component of about PeV. It is based on the spectra of nucleons and electrons obtained by the authors in the framework of the superdiffusion model of nonclassical cosmic ray diffusion, which have a knee, on the assumption that nucleons and electrons are accelerated by the same type sources and their propagation in an inhomogeneous turbulent galactic medium is characterized by the same diffusion coefficient, and also on the knee in the spectrum of the electronic component in the region of TeV, established in the DAMPE experiment. It is shown that pevatrons, which form a knee in the spectrum of the cosmic ray nucleon component of about PeV, are located at distances of the order of kpc from the Earth. [ABSTRACT FROM AUTHOR]

Paper contains the first results on the development of a SPHERE-3 telescope for the primary cosmic ray studies in 1–1000 PeV energy range using reflected and direct Cherenkov light generated by extensive air showers. It also sheds some light on the development of our new approach to the design of the new telescope. [ABSTRACT FROM AUTHOR]