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The Microwave SQUID Multiplexer (μ MUX) is the device of choice for the readout of a large number of low-temperature detectors in a wide variety of experiments within the fields of astronomy and particle physics. While it offers large multiplexing factors, the system noise performance is highly dependent on the cold- and warm-readout electronic systems used to read it out, as well as the demodulation domain and parameters chosen. In order to understand the impact of the readout systems in the overall detection system noise performance, first, we extended the available μ MUX simulation frameworks, including additive and multiplicative noise sources in the probing tones (i.e., phase and amplitude noise), along with the capability of demodulating the scientific data, either in the resonator's phase or the scattering amplitude. Then, considering the additive noise as a dominant noise source, the optimum readout parameters to achieve minimum system noise were found for both open-loop and flux-ramp demodulation schemes in the aforementioned domains. Later, we evaluated the system noise sensitivity to multiplicative noise sources under the optimum readout parameters. Finally, as a case study, we evaluated the optimal demodulation domain and the expected system noise level for a typical software-defined radio readout system. This work leads to an improved system performance prediction and noise engineering based on the available readout electronics and the selected demodulation domain. [ABSTRACT FROM AUTHOR]

Radio-frequency (RF) cavities, previously employed in particle physics, quantum computing, and gravitational wave research, offer unique advantages in terms of sensitivity and non-invasiveness as a method of sensing motion in both macroscopic and microscopic systems. This research aims to address how an RF cavity can effectively detect and characterize the low-frequency vibratory motion of a room-temperature mm-scale levitated particle. In this case, the particle in question is a diamagnetically levitated slab of highly oriented pyrolytic graphite. Cavity-based identification of the slab's rigid-body modes is substantiated by calculations of the force acting on the particle and validated through slow-motion video object tracking. We find that this system can accurately measure oscillations in all six center-of-mass degrees of freedom. Calculations indicate that this system could potentially detect forces on the scale of tens of femto-Newtons and center of mass displacements of less than 10 nm. This work provides a non-invasive method of conducting position and vibration measurements in the field of levitodynamics without the ultra-cold temperatures or bulky precision laser setups that superconducting quantum interference devices and conventional interferometric methods utilize. [ABSTRACT FROM AUTHOR]

Muons are part of natural cosmic radiation but can also be generated at spallation sources for material science and particle physics applications. Recently, pulsed muons have been used to characterize the density of free charge carriers in semiconductors and their recombination lifetime. Muon beam irradiation can also result in the formation of dilute levels of crystal defects in silicon. These crystal defects are only detected in high carrier lifetime silicon samples that are highly sensitive to defects due to their long recombination lifetimes. This work investigates the characteristics of these defects in terms of their formation, recombination activity, and deactivation. Charge carrier lifetime assessments and photoluminescence imaging have great sensitivity to measure the generated defects in high-quality silicon samples exposed to ∼4 MeV (anti)muons and their recombination activity despite the extremely low concentration. The defects reduce the effective charge carrier lifetime of both p- and n-type silicon and appear to be more detrimental to n-type silicon. Defects are created by transmission of muons through the wafer, and there are indications that slowed or implanted muons may create additional defects. In a post-exposure isochronal annealing study, we observe that annealing at temperatures of up to 450 °C does not by itself fully deactivate the defects. A recovery of charge carrier lifetime was observed when the annealing was combined with Al2O3 surface passivation, probably due to passivation of bulk defects from hydrogen from the dielectric film. [ABSTRACT FROM AUTHOR]

The document "Contributors to the Emerging Investigators collection 2024: Part 2" from Chemical Communications profiles various researchers in the field of chemistry. It highlights their academic backgrounds, research interests, and current positions at different universities around the world. The researchers mentioned in the document are engaged in diverse areas of study, including chemoproteomic technologies, spatially organized biochemistry, organic semiconducting materials, and molecular catalyst development, among others. The document provides a comprehensive overview of the academic and research achievements of these emerging investigators in the field of chemistry. [Extracted from the article]

The intricate behavior of particle acceleration and transport mechanisms complicates the overall efforts in formulating a comprehensive understanding of solar energetic particle (SEP) events; these efforts include observations of low-energy particles (from tens of keV to hundreds of MeV) by space-borne instruments and measurements by the ground-based neutron monitors of the secondary particles generated in the Earth atmosphere by SEPs in the GeV range. Numerous space-borne missions provided good data on the nature/characteristics of these solar particles in past solar cycles, but more recently—concurrently with the rise toward the maximum of solar cycle 25—the High-Energy Particle Detector (HEPD-01) proved to be well suited for the study of solar physics and space weather. Its nominal 30–300 MeV energy range for protons can enlarge the detection capabilities of solar particles at low Earth orbit, closer to the injection limit of many SEP events. In this work, we characterize three SEP events within the first six months of 2022 through spectral and velocity dispersion analysis, assessing the response of HEPD-01 to >M1 events. [ABSTRACT FROM AUTHOR]

In the metaphysics of science, it is often held that higher-level properties are grounded in micro-physical properties. According to many philosophers, however, phenomenal consciousness resists this view. Many famous arguments in Philosophy of Mind have been given to reject this notion. In this paper, we argue that there is something odd about the idea that phenomenal consciousness is a special case in science and give a constructive proposal on how consciousness can fit in the natural world. To do so, we will first introduce a general notion of what grounding is. Then, we will briefly explain how the arguments for the specialness of phenomenal consciousness work by considering two famous examples, namely the zombie and the knowledge argument. In a further step, we will briefly discuss two cases from other areas in science, i.e., in particle physics and chemistry. We will demonstrate that the standard view about the reductive relation does not hold, even in these paradigm cases of the natural sciences. If what we argue is true, we think that most arguments from phenomenal consciousness cannot defeat physicalism per se. Finally, we will introduce an alternative way to naturalize phenomenal consciousness. [ABSTRACT FROM AUTHOR]

In 1995, the ATLAS Experiment at the Large Hadron Collider embarked on an ambitious journey, driven by a passion to ignite curiosity and inspire future scientists. Our quest wasn’t just about uncovering the universe’s mysteries; it was a cosmic odyssey to share the thrill of scientific exploration with all. Our exploratory collection included engaging classroom activities, a dynamic website, captivating videos, a vibrant YouTube channel, global social media connections, and a captivating planetarium show, all intertwined with the exciting search for the elusive Higgs Boson. This scientific program celebrates the enduring curiosity of humanity and the passion that fuels discovery. [ABSTRACT FROM AUTHOR]

In this paper, we show that loop-induced processes involving new physics particles can readily satisfy Landau Equation and trigger triangular singularities at high-energy colliders, leading to fully visible Standard Model final states. In addition, a t-channel triangular singularity can also occur during particle scattering processes that may extend to low momentum exchange. We discuss several typical scenarios in supersymmetric and extended Higgs models, and three types of final-state kinematic features at the collider. Four-particle vertices in new physics can play a significant role in high energy diagrams. We identify an “everything on shell” triangular singularity diagram only involving bosonic couplings, which has the potential to completely avoid large virtuality suppression. We further show that such a virtuality-free diagram is missing in the Standard Model at electroweak scale, and it becomes available in new physics models. [ABSTRACT FROM AUTHOR]

Chae’s analyses on GAIA observations of wide binary stars have fortified the paradigm of extended gravity with particular attention to MOND-like theories. We recall that, starting from the origin of Einstein’s general relativity, the request of Mach on the structure of the theory has been the core of the foundational debate. This issue is strictly connected with the nature of the mass–energy equivalence. This was exactly the key point that Einstein used to derive the same general relativity. On the other hand, the current requirements of particle physics and the open questions within extended gravity theories, which have recently been further strengthened by the analyses of GAIA observations, request a better understanding of the Equivalence Principle. By considering a direct coupling between the Ricci curvature scalar and the matter Lagrangian, a nongeodesic ratio between the inertial and gravitational masses can be fixed and MOND-like theories are retrieved at low energies. [ABSTRACT FROM AUTHOR]

Simulation of quantum field theories and fundamental interactions is one of the most challenging tasks in modern particle physics. Classical computers generally fail to reproduce accurate results when it comes to strongly coupled theories such as QCD. Recent developments in quantum technologies open up the possibility of simulating such physical regimes by using quantum computers. In this paper, we study the quantum resource related to the simulability of a quantum theory, i.e. non-stabilizerness for Lattice Gauge Theory (LGT) with discrete symmetry gauge groups. We show that enforcing gauge constraints for ℤl LGTs has no cost in terms of this resource and discuss the relation between non-abelianity of the gauge group with the average non-stabilizerness of the gauge invariant Hilbert space. [ABSTRACT FROM AUTHOR]

The investigation of charm physics plays an important role in checking the Standard Model’s description of strong and weak interactions, validating its predictions for particle physics, and exploring new physics beyond the Standard Model. Using a large dataset from e+e− annihilation, BESIII has conducted comprehensive and extensive studies in the areas of hadronic, leptonic and semileptonic decays. This proceeding presents an overview of the recent researches and discoveries by BESIII on decays of charmed baryons, charmed mesons and charmonium states, highlighting their significance in advancing the understanding of new physics, experimental determination of physical parameters and improvement of measurement precision. [ABSTRACT FROM AUTHOR]

One of the fundamental goals of particle physics is to gain a microscopic understanding of the strong interaction. Electromagnetic form factors quantify the structure of hadrons in terms of charge and magnetization distributions. While the nucleon structure has been investigated extensively, data on hyperons are still scarce. It has recently been demonstrated that electron-positron annihilations into hyperon-antihyperon pairs provide a powerful tool to investigate their inner structure. We present a method useful for hyperon-antihyperon pairs of different types which exploits the cross section enhancement due to the effect of vacuum polarization at the J/ψ resonance. Using the 10 billion J/ψ events collected with the BESIII detector, this allows a precise determination of the hyperon structure function. The result is essentially a precise snapshot of the Λ ¯ Σ 0 (Λ Σ ¯ 0 ) transition process, encoded in the transition form factor ratio and phase. Their values are measured to be R = 0.860 ± 0.029(stat.) ± 0.015(syst.), Δ Φ Λ ¯ Σ 0 = (1.011 ± 0.094 (stat.) ± 0.010 (syst.)) r a d and Δ Φ Λ Σ ¯ 0 = (2.128 ± 0.094 (stat.) ± 0.010 (syst.)) r a d . Furthermore, charge-parity (CP) breaking is investigated in this reaction and found to be consistent with CP symmetry. Investigating the inner structure of baryons is important to further our understanding of the strong interaction. Here, the BESIII Collaboration extracts the absolute value of the ratio of the electric to magnetic form factors and its relative phase for e + e − → J/ψ → ΛΣ decays, enhancing the signal thanks to the vacuum polarisation effect at the J/ψ peak. [ABSTRACT FROM AUTHOR]

We outline a method of beamed power for propulsion that utilizes relativistic electron beams. The physics of charged particle beam propagation in the space plasma environment is discussed and the long-range (> 100 AU) advantage of relativistic electron beams is emphasized. A preliminary statite-based beam emitter for powering probes to 0.1c is proposed and the challenges in beamed-power uses are explored. • The potential for a relativistic electron beam to have dramatically longer beam ranges than other forms of beam-driven propulsion is revealed • The propagation of the beam through the space plasma is discussed and areas for further work identified • It is shown that the longer range of the beam permits interstellar probes to be driven to relevant speeds above 0.1c with feasible power levels in the GW class for implementation. • The key remaining obstacle, the conversion from the electron beam to rocket thrust, is identified and some possible approaches discussed • A path to implementation, using plasma sailing to hover the beam platform near the sun, and thermoelectric power conversion to generate the power for the beam, is presented. [ABSTRACT FROM AUTHOR]

Within the phenomenology of particle physics, the theoretical model of 4-zero textures is validated using a chi-square criterion that compares experimental data with the computational results of the model. Traditionally, analytical methods that often imply simplifications, combined with computational analysis, have been used to validate texture models. In this paper, we propose a new meta-heuristic variant of the differential evolution algorithm that incorporates aspects of the particle swarm optimization algorithm called "HE-DEPSO" to obtain chi-squared values that are less than a bound value, which exhaustive and traditional algorithms cannot obtain. The results show that the proposed algorithm can optimize the chi-square function according to the required criteria. We compare simulated data with experimental data in the allowed search region, thereby validating the 4-zero texture model. [ABSTRACT FROM AUTHOR]

Dark matter research, aimed at unraveling astrophysical enigmas, faces the challenge of lacking concrete evidence connecting dark matter with the observable universe in both experimental and theoretical particle physics. Our study investigates a simplified extension to the Standard Model (SM) where SM fermion interacts with a hypothetical vector dark matter (DM) particle in high-energy collisions, mediated by a proposed massive spin-1 particle, Z ′ . We specifically explore vector DM pair production through fermion annihilation in this mediator, focusing on a near-resonance condition ( m χ ∼ M Z ′ / 2 ). This includes examining monophoton production, a SM signal, as a result of initial-state radiation. We also calibrate the coupling constants between DM and SM particles relative to Planck satellite thermal relic density data, particularly near a resonance where traditional models anticipate more relic density suppression. Our findings, consistent with expected relic density at resonance regimes, suggest mass ranges and coupling constants for these DM particles that align with collider and astrophysical limits, to be validated in CLIC and LHC settings. [ABSTRACT FROM AUTHOR]

Due to the large volume of data, presence of high noise and abundance of similar topics, hot topic detection algorithms find it difficult to detect topics accurately from microblog datasets. Here, we propose a novel clustering technique that is able to group hot topics from microblogs even in the presence of large amount of noise and similar topics. We use a combination of centroid- based celestial clustering (CBCC), a nature-inspired clustering mechanism derived from the principles of particle physics, and PSO- based approach to achieve this. We experiment our methods on four different microblog datasets, two of which include a large number of outliers. We have evaluated our methods using statistical parameters such as precision, recall, error rate, F 1 score and average in group proportion (AIGP) and comparison with other popular topic detection algorithms has shown that our methods yield significant advantages. [ABSTRACT FROM AUTHOR]

The Super Tau Charm Facility (STCF) is a state-of-the-art electron-positron collider operating in the center-of-mass energy range of 2–7GeV and achieving a peak luminosity of more than 0.5×1035cm−2s−1, which is pivotal for advancing particle physics research. The DIRC-like time-of-flight (DTOF) detector is one of the crucial components of the STCF, designed to identify high-momentum charged particles with high precision. A significant element of the DTOF is the microchannel plate photomultiplier tube (MCP-PMT), known for its exceptional time resolution in the detection of Cherenkov light. With the STCF expected to operate for over a decade, stringent requirements are imposed on the MCP-PMT, requiring an integrated anode charge (IAC) in excess of 10C/cm2. In this paper, the lifetime of the single anode MCP-PMT prototypes is investigated and a multi-anode MCP-PMT design is presented. The results show that the lifetime of the single anode MCP-PMT is greater than 11C/cm2 when a 6 nm-thick ALD layer is deposited on the inner surface of the MCP and an electron scrubbing dosage of 0.75μA⋅h/cm2 is applied to the MCP. The lifetime is expected to be further improved by increasing the electron scrubbing dosage and optimizing the ALD layer. The studies on the single anode MCP-PMTs will be applied to the development of the long-life multi-anode MCP-PMT. [ABSTRACT FROM AUTHOR]

The authors compare the structures and methods in the theory of causal fermion systems with approaches to fundamental physics based on division algebras, in particular the octonions. It is found that octonions and, more generally, tensor products of division algebras come up naturally to describe the symmetries of the vacuum configuration of a causal fermion system. This is achieved by associating the real and imaginary octonion basis elements with the neutrino and charged sectors of the vacuum fermionic projector, respectively. Conversely, causal fermion systems provide octonionic theories with spacetime structures and dynamical equations via the causal action principle. In this way, octonionic theories and causal fermion systems complement each other. [ABSTRACT FROM AUTHOR]

It is important to test the possible existence of fifth forces, as ultralight bosons that would mediate these are predicted to exist in several well-motivated extensions of the Standard Model. Recent work indicated asteroids as promising probes, but applications to real data are lacking so far. Here we use the OSIRIS-REx mission and ground-based tracking data for the asteroid Bennu to derive constraints on fifth forces. Our limits are strongest for mediator masses m ~ (10−18-10−17) eV, where we currently achieve the tightest bounds. These can be translated to a wide class of models leading to Yukawa-type fifth forces, and we demonstrate how they apply to U(1)B dark photons and baryon-coupled scalars. Our results demonstrate the potential of asteroid tracking in probing well-motivated extensions of the Standard Model and ultralight bosons near the fuzzy dark matter range. Asteroid tracking has been demonstrated as a promising and prominent probe of fifth forces arising in several well-motivated models beyond the Standard Model of particle physics. The authors use the state-of-art tracking data for the asteroid Bennu from the OSIRIS-REx mission to derive the tightest limits on fifth forces and ultralight dark matter at the lengths of solar-system objects. [ABSTRACT FROM AUTHOR]

Fuzzy dark matter (FDM), comprised of ultralight (⁠|$m \sim 10^{-22}\,{\rm eV}$|⁠) boson particles, has received significant attention as a viable alternative to cold dark matter (CDM), as it approximates CDM on large scales (⁠|${\gtrsim}1$|  Mpc) while potentially resolving some of its small-scale problems via kiloparsec-scale quantum interference. However, the most basic FDM model, with one free parameter (the boson mass), is subject to a tension: small boson masses yield the desired cores of dwarf galaxies but underpredict structure in the Lyman-α forest, while large boson masses render FDM effectively identical to CDM. This Catch-22 problem may be alleviated by considering an axion-like particle with attractive particle self-interactions. We simulate an idealized FDM halo with self-interactions parametrized by an energy decay constant |$f \sim 10^{15}~\rm {GeV}$| related to the axion symmetry-breaking conjectured to solve the strong-CP problem in particle physics. We observe solitons, a hallmark of FDM, condensing within a broader halo envelope, and find that the density profile and soliton mass depend on self-interaction strength. We propose generalized formulae to extend those from previous works to include self-interactions. We also investigate a critical mass threshold predicted for strong interactions at which the soliton collapses into a compact, unresolved state. We find that the collapse happens quickly, and its effects are initially contained to the central region of the halo. [ABSTRACT FROM AUTHOR]

This document provides a summary of a special issue titled "Advances in Particle Acceleration: Novel Techniques, Instruments, and Applications." The special issue covers various topics related to particle acceleration. It discusses recent advancements in accelerator technologies, including new materials, fabrication techniques, and novel acceleration methods. The document specifically focuses on the advancements in radiotherapy methods for cancer treatment, as well as the development of radioisotope therapy. It also explores the pursuit of compact light sources and advancements in accelerator technologies for enhanced miniaturization, power capacity, reliability, sustainability, and cost-efficiency. The special issue includes several papers that cover topics such as beam dynamics software, RF cavity optimization, niobium cavity coating, efficient accelerator lattice design, plasma accelerator concept, and improvements to electrostatic dust accelerators. Overall, the special issue provides valuable insights into the latest advancements in particle acceleration. [Extracted from the article]

The Super Tau-Charm Facility (STCF) is a significant initiative for accelerator-based particle physics in China. Electromagnetic Calorimeter (ECAL) is one of the important detectors of STCF, which is tasked with the accurate measurement of photons. STCF ECAL employs pure Cesium iodide (pCsI) as its scintillation crystal and uses a large-area avalanche photodiode (APD) as a photoelectric conversion device. High luminosity of STCF results in significant background levels, leading to pileups challenging conventional signal processing. In this paper, a pile-up correction algorithm called “pipeline optimal filtering” is proposed, and a background simulation platform is built to verify the measurement effect of the algorithm on energy and time. [ABSTRACT FROM AUTHOR]

Cosmic string networks are expected to generate a characteristic stochastic gravitational wave background that may be within the reach of current and upcoming gravitational wave detectors. A detection of this spectrum would provide invaluable information about the physics of the early universe, as it would allow us to probe the sequence of phase transitions that happened in the distant past. Here, I review the emission of gravitational waves by Nambu–Goto cosmic strings—thin cosmic strings that couple strongly to gravity only—and by superconducting strings—strings that carry electromagnetic currents. A comparison between the stochastic gravitational wave background predicted in these two very distinct string-forming scenarios reveals that this spectrum may have signatures that may allows us to discriminate between them observationally. The stochastic gravitational wave background generated by cosmic string networks may then enable us to uncover not only the energy-scale of the string-forming phase transition, but the underlying particle physics scenario as well. [ABSTRACT FROM AUTHOR]

Proton radiography is an essential diagnostic for studying magnetic fields in high energy density physics experiments. Protons are born in a fusion implosion, traverse the plasma, and are detected on CR-39 solid state nuclear track detectors. Here, it is shown that there is an intrinsic non-uniformity in ∼ 15 MeV D3He proton radiography data. The increasing angle between the proton trajectory and the center of the detector results in the proton traveling through more detector stack material. As the protons travel through more material and lose energy, the proton energy spectrum gets wider. Protons at the lower end of the spectrum can therefore be lost. The nominal filtering results in protons being ranged out at large angles, causing the intrinsic non-uniformity. This angular effect is confirmed with both OMEGA experiments and Geant4 simulations. It is found that reducing the filtering between the pieces of CR-39 in the detector stack mitigates this effect. Results from accelerator experiments show that this reduced filtering does not impact the detection efficiency of the CR-39. Accounting for this intrinsic fluence non-uniformity is essential for magnetic field reconstruction techniques using proton radiographs. [ABSTRACT FROM AUTHOR]

The CREDO-Maze project is the concept for a network of stations recording local, extensive cosmic ray air showers. Each station consists of four small scintillation detectors and a control unit that monitors the cosmic ray flux 24 h a day and transmits the results to the central server. The modular design of each array allows the results to be used in educational classes on nuclear radiation, relativistic physics, and particle physics and as a teaching aid in regular school classrooms and more. As an example, we present here some preliminary results from the CREDO-Maze muon telescope missions to the Arctic and down into a deep salt mine, as well as the first shower-particle correlation measurements from a table-top experiment at Walailak University. These experiments show that the different geometric configurations of the CREDO-Maze detector set can be used for projects beyond the scope of the secondary school curriculum, and they can form the basis of student theses and dissertations at universities. [ABSTRACT FROM AUTHOR]

This paper reviews the many twists and turns in the long journey that culminated in ignition in late 2022 using the laser heated indirect-drive approach to imploding DT filled targets at the National Ignition Facility (NIF), located at the Lawrence Livermore National Laboratory (LLNL). We describe the early origins of the Laser Program at LLNL and key developments such as the paradigm shifting birth of high energy density physics (HEDP) studies with lasers, changes in choice of laser wavelength, and the development of key diagnostics and computer codes. Fulfilling the requirements of the multi-faceted Nova Technical Contract was a necessary condition for the approval of the NIF, but more importantly, the end of the Cold War and the cessation of nuclear testing were key catalysts in that approval, along with the ready-and-waiting field of HEDP. The inherent flexibility of the field of laser driven inertial confinement fusion played a fundamental role in achieving success at the NIF. We describe how the ultimately successful ignition target design evolved from the original "point design" target, through the lessons of experiment. All key aspects of that original design changed: The capsule's materials and size were changed; the hohlraum's materials, size, laser entrance hole size, and gas fills were also all changed, as were the laser pulse shapes that go along with all those changes. The philosophy to globally optimize performance for stability (by raising the adiabat and thus lowering the implosion convergence) was also key, as was progress in target fabrication, and in increasing NIF's energy output. The persistence of the research staff and the steadfast backing of our supporters were also necessary elements in this success. We gratefully acknowledge seven decades of researcher endeavors and four decades of the dedicated efforts of many hundreds of personnel across the globe who have participated in NIF construction, operation, target fabrication, diagnostic, and theoretical advances that have culminated in ignition. [ABSTRACT FROM AUTHOR]

Inhalation of airborne fibers such as asbestos has been a concern for toxicological response that can affect lung tissues. This study aims at developing a computational model that predicts experimental measurements for fibrous particle filtration in nylon mesh screens and elucidates the physics underlying particle dynamics. The filtration process is operated at the constant airflow of 7 cm/s for particles with aerodynamic diameters between 0.8 and 10 μm corresponding to the particle length between 11.4 and 54.3 μm and particle diameter between 0.6 and 8.5 μm. The aerodynamic diameter characterizes particle sizes having different shapes and densities with a single dimension. This two-dimensional (2D) computational model with a single fiber represents the infinite array of screen fibers parallel to each other and screen collection efficiency is estimated by a previously proposed formula taking into account particle laden flow crossing two crossed fibers. The orientations of fibrous particles in a three-dimensional form are projected to the 2D plane and analyzed in the cross-sectional view of a screen. The simulations generally well predict experimental profiles of the screen collection efficiency as a function the aerodynamic diameter and screen pore size. The analyses carried out contain the distribution of particle fraction deposited along fiber surface, particle pathlines, particle distribution in the gas flow, and breakdown of forces acting on a single particle. [ABSTRACT FROM AUTHOR]

Cost-effective production method for making density-controllable monodisperse spheres is demonstrated. A sodium alginate aqueous solution containing gelatin is emulsified with canola oil. The droplet surface is covered with a calcium alginate membrane by dropping the emulsion into a calcium lactate aqueous solution. The content of the canola oil can control the sphere's density. To demonstrate the applicability of the spheres to experimental research, rheological measurements of the suspensions of the spheres were performed. The effective viscosity agrees with the theoretical formula at volume fractions of 0.7 % – 11.7 %. The demonstration highlights that the spheres can function as neutrally buoyant solid particles in studies for the physics of fluids. [ABSTRACT FROM AUTHOR]

Over the past 60 years, particle physics has seen the maturation of its Standard Model and an enormous change in the character of the experiments that have defined it. I have had the good fortune to participate in and help shape this evolution. [ABSTRACT FROM AUTHOR]

Amid all candidates of physics beyond the Standard Model, string theory provides a unique proposal for incorporating gauge and gravitational interactions. In string theory, a four-dimensional theory that unifies quantum mechanics and gravity is obtained automatically if one posits that the additional dimensions predicted by the theory are small and curled up—a concept known as compactification. The gauge sector of the theory is specified by the topology and geometry of the extra dimensions, and the challenge is to reproduce all of the features of the Standard Model of particle physics from them. We review the state of the art in reproducing the Standard Model from string compactifications and summarize the lessons drawn from this fascinating quest. We describe novel scenarios and mechanisms that string theory provides to address some of the Standard Model puzzles as well as the most frequent signatures of new physics that could be detected in future experiments. We then comment on recent developments that connect, in a rather unexpected way, the Standard Model with quantum gravity and that may change our field theory notion of naturalness. [ABSTRACT FROM AUTHOR]

The direct detection of dark matter constituents, particularly weakly interacting massive particles (WIMPs), is central to particle physics and cosmology. In this paper, we develop the formalism for WIMP–nucleus-induced transitions from isomeric nuclear states, with particular focus on the experimentally interesting target 180Ta. [ABSTRACT FROM AUTHOR]

The High Intensity Muon Beams (HIMB) project at the Paul Scherrer Institute (PSI) will deliver muon beams with unprecedented intensities of up to 10 10 muons / s for next-generation particle physics and material science experiments. This represents a hundredfold increase over the current state-of-the-art muon intensities, also provided by PSI. We performed beam dynamics optimisations and studies for the design of the HIMB beamlines MUH2 and MUH3 using Graphics Transport, Graphics Turtle, and G4beamline, the latter incorporating PSI's own measured π + cross-sections and variance reduction. We initially performed large-scale beamline optimisations using asynchronous Bayesian optimisation with DeepHyper. We are now developing an island-based evolutionary optimisation code glyfada based on the Paradiseo framework, where we implemented Message Passing Interface (MPI) islands with OpenMP parallelisation within each island. Furthermore, we implemented an island model that is also suitable for high-throughput computing (HTC) environments with asynchronous communication via a Redis database. The code interfaces with the codes COSY INFINITY and G4beamline. The code glyfada will provide heterogeneous island model optimisation using evolutionary optimisation and local search methods, as well as part-wise optimisation of the beamline with automatic advancement through stages. We will use the glyfada for a future large-scale optimisation of the HIMB beamlines. [ABSTRACT FROM AUTHOR]

This paper attempts to classify various blinding strategies used in particle physics. It argues that the blinding technique is not used consistently throughout searches for new physics. More importantly, the blinding technique, in its traditional sense, cannot be applicable for many current and future searches when the statistical precision of data significantly exceeds the current level of our understanding of Standard Model (SM) backgrounds. [ABSTRACT FROM AUTHOR]

During magnetospheric substorms, plasma from magnetic reconnection in the magnetotail is thought to reach the inner magnetosphere and form a partial ring current. We simulate this process using a fully kinetic 3D particle‐in‐cell (PIC) numerical code along with a global magnetohydrodynamics (MHD) model. The PIC simulation extends from the solar wind outside the bow shock to beyond the reconnection region in the tail, while the MHD code extends much further and is run for nominal solar wind parameters and a southward interplanetary magnetic field. By the end of the PIC calculation, ions and electrons from the tail reconnection reach the inner magnetosphere and form a partial ring current and diamagnetic current. The primary source of particles to the inner magnetosphere is bursty bulk flows (BBFs) that originate from a complex pattern of reconnection in the near‐Earth magnetotail at xGSM=−18RE ${x}_{\text{GSM}}=-18{R}_{\mathrm{E}}$ to −30RE ${-}30{R}_{\mathrm{E}}$. Most ion acceleration occurs in this region, gaining from 10 to 50 keV as they traverse the sites of active reconnection. Electrons jet away from the reconnection region much faster than the ions, setting up an ambipolar electric field allowing the ions to catch up after approximately 10 ion inertial lengths. The initial energy flux in the BBFs is mainly kinetic energy flux from the ions, but as they move earthward, the energy flux changes to enthalpy flux at the ring current. The power delivered from the tail reconnection in the simulation to the inner magnetosphere is >2×1011 ${ >} 2\times 1{0}^{11}$ W, which is consistent with observations. Plain Language Summary: During intervals of increased solar activity, the magnetic field in Earth's stretched night‐side tail undergoes intense reconfiguration that can energize particles. This process is called magnetic reconnection. Ions and electrons from reconnection can reach the inner magnetosphere. In this paper, we simulate this process using a novel model that includes Earth's global magnetic field configuration and self‐consistently models particle physics for both electrons and ions. We find that the particles are accelerated significantly near the sites of magnetic field reconfiguration with ions gaining 10 s of keV energy. As they propagate earthward, they end up contributing energetically to the formation of a ring current system partially encircling Earth. Key Points: Ions and electrons accelerated by 10–50 keV near the magnetotail reconnection can reach the inner magnetosphereA partial ring current is formed during the simulation, with highest energy flux between midnight and duskThe ion and electron energy fluxes are mostly kinetic in the reconnection region but change to enthalpy flux earthward [ABSTRACT FROM AUTHOR]

This article provides a comprehensive overview of the Nobel Prizes in Chemistry related to computational chemistry. It explores the history and development of the field, highlighting the contributions of notable scientists and their groundbreaking work in areas such as chemical dynamics, molecular structure, and electronic structure calculations. The article also discusses the Nobel Prizes awarded in specific years, recognizing the achievements of laureates and their significant research contributions. It acknowledges the underrepresentation of women in Nobel Prizes and reflects on the author's personal experiences and hopes for the future of computational chemistry. [Extracted from the article]

High-performance radiation detectors are essential in many sectors spanning medical diagnostics, nuclear control, and particle physics. Ultrawide bandgap semiconductor materials have become one of the most promising candidates due to their excellent performance. Here, based on β-Ga2O3, a Schottky diode-type alpha particle detector was demonstrated. In order to reduce the reverse leakage current of the large-area device, the metal-oxide electrode PtOx was introduced to form high-barrier contacts (1.83 eV) with Ga2O3. The device exhibits a low leakage current density of 63 pA/cm2 at −100 V and apparent energy spectra of 241Am generated alpha particles with an energy of 5.486 MeV at various reverse voltages from −40 to −120 V. The charge collection efficiency (CCE) and energy resolution of the device (at −120 V) are 31.7% and 15.3%, respectively. Meanwhile, the mechanism of interaction between alpha particles and β-Ga2O3 was analyzed, and a 45° oblique incidence was adopted to increase the deposited energy of alpha particles in the depletion region. Furthermore, the differences between actual CCE and theoretical CCE are investigated as guidance for further improving detector performance. This work reveals the great potential and good prospects of Ga2O3 as an economical, efficient, and radiation-resistant ionizing radiation detector. [ABSTRACT FROM AUTHOR]

Low Gain Avalanche Diodes (LGADs) are silicon sensors designed to achieve an internal gain in the order of 10 through the impact ionization process. The development of LGADs was pushed forward by their application in High Energy Physics (HEP) experiments, where they will be employed to provide measurements of the time of arrival of minimum ionizing particles with a resolution of around 30 ps. The initial technological implementation of the sensors constrains their minimum channel size to be larger than 1 mm², in order to reduce inefficiencies due to the segmentation of the gain structure. The gain of the sensors is kept in the order of 10 to limit the sensor shot noise and their power consumption. In photon science, the gain provided by the sensor can boost the signal-to-noise ratio of the detector system, effectively reducing the x-ray energy threshold of photon counting detectors and the minimum x-ray energy where single photon resolution is achieved in charge integrating detectors. This can improve the hybrid pixel and strip detectors for soft and tender x-rays by simply changing the sensor element of the detector system. Photon science applications in the soft and tender energy range require improvements over the LGADs developed for HEP, in particular the presence of a thin entrance window to provide a satisfactory quantum efficiency and channel size with a pitch of less than 100 µm. In this review, the fundamental aspects of the LGAD technology are presented, discussing also the ongoing and future developments that are of interest for photon science applications. [ABSTRACT FROM AUTHOR]

Weakly nonlocal (WNL) Quantum Field Theories (QFTs) may define a new class of UV-completions in particle physics and gravity, without introducing any new elementary particle. One problematic issue is how to realize spontaneous symmetry breaking without introducing an infinite tower of ghosts in the perturbative spectrum. In this article, a WNL extension of the Standard Model (SM) is proposed: the Fuzzy Standard Model (FSM). It is a smooth deformation of the SM based on covariant star-products of fields. This new formalism realizes electroweak symmetry breaking without ghosts at tree-level. We give evidence that the FSM exhibits Vainshtein screening, aka classicalization, in the deep-UV. This could solve the electroweak hierarchy problem if it occurs at the TeV-scale. [ABSTRACT FROM AUTHOR]

The Follow-up X-ray telescope (FXT) is one of the instruments on board the Einstein Probe (EP) satellite of the Chinese Academy of Sciences (CAS) which was launched in January 2024. The EP mission is dedicated to the study of time-domain high-energy astrophysics, utilising a lobster-eye-based wide-field telescope, complemented by an eROSITA-like optics for follow-up observations. Max Planck Institute for Extraterrestrial Physics (MPE) has provided hardware and conducted measurement campaigns at its test facilities as part of a European contribution to Einstein Probe by ESA, and in addition the eROSITA flight spare mirror assembly as the second FXT module. Three FXT mirror assemblies – structural-thermal, qualification and flight models – have been manufactured. All components underwent acceptance testing using X-rays, followed by the installation of X-ray baffles for stray-light rejection. Subsequently, they underwent environmental tests and X-ray performance evaluations. The final tests of the qualification model, serving as a flight spare, and the flight model included an X-ray calibration at various photon energies ranging from about 0.3 keV to 8 keV. All tests were performed at MPE's test facilities: the laboratory for vibration and thermal-vacuum testing, and the PANTER X-ray facility. Reported are the setups and the results of the respective test sequences, focusing on the qualification and flight mirror assemblies. After delivery to China, all mirror assemblies were subjected to complementary measurements in the X-ray test facility of the Institute for High Energy Physics (IHEP) of CAS. • Design of the Follow-up X-ray telescope (FXT) on Einstein Probe. • FXT model philosophy and test matrix. • FXT X-ray test and calibration results. [ABSTRACT FROM AUTHOR]