Abstract This work provides an analysis of p T spectra for identified hadrons generated during gold–gold collisions at a center-of-mass energy ( s N N ) of 11.5 GeV. The data, recorded by the STAR detector at the Relativistic Heavy Ion Collider, is evaluated using predictions from phenomenological models. Specifically, we compare the outcomes of Monte Carlo simulations from Pythia 8.3 and EPOS (comprising EPOS4 and EPOSLHC) with experimental observations. Our investigation focuses on π ± , K ± , and (anti-)proton spectra measured at mid-rapidity (∣ y ∣ < 0.1) across nine distinct centrality classes. In the case of π ± , EPOS4 model shows good agreement with the data only in the low p T region. However, it successfully reproduces the results across the entire p T range for the last three centrality classes for pions yields. In the case of K ± , EPOS4 exhibit good agreement with the experimental data. For proton and (anti-)proton, this model mostly underestimates in high- p T region, likely due to the reduced interaction volume and lower rescattering probability. In contrast, Pythia 8.3 often overpredicts pion yields and provides consistent representations for kaons and for (anti-)protons, Pythia 8.3 and EPOSLHC fails to describe the data. Pythia 8.3 mostly overestimates the data in the case of proton. EPOS4 demonstrates a good description of pion spectra compared to Pythia 8.3, largely attributable to its inclusion of hadronic rescattering effects. Meanwhile, EPOSLHC shows better alignment with experimental data in the case of kaons and proton for the entire p T range while for pions it also better reproduced the result at higher p T only. At higher p T , EPOSLHC exhibits a suppression relative to the experimental data, indicating limitations of the model description in a momentum region where collective flow effects are expected to be minimal. EPOS4 and EPOSLHC outperform Pythia 8.3, primarily due to their ability to incorporate correlated flow dynamics and hadronic rescattering effects. In contrast, Pythia 8.3 lacks these mechanisms, leading to less precise spectral descriptions. None of the models accurately replicate the experimental data for the (70–80)% centrality class likely due to the absence of collective effects and the increased role of non-equilibrium dynamics in these events. Additionally, the extracted freeze-out parameters indicate a rise in effective temperature and a decrease in the non-extensive parameter with increasing centrality. These trends suggest greater system excitation and more rapid thermal equilibration in highly central collisions.

Abstract The fusion-evaporation excitation functions in the reactions of $^{12}$C/$^{16}$O + $^{165}$Ho, $^{12}$C + $^{198}$Pt/$^{208}$Pb/$^{238}$U, $^{16}$O + $^{148}$Sm/$^{208}$Pb/$^{238}$U, $^{20}$Ne + $^{208}$Pb/$^{209}$Bi and $^{36,40}$Ar + $^{182}$W/$^{185}$Re/$^{187}$Os are systematically investigated by a combined approach of the barrier distribution and statistical theory. The production cross sections of proton-rich nuclides $^{211-214}$U, $^{214-218}$Np and $^{216-220}$Pu are estimated for the pure neutron and charged particle evaporation. The kinetic energy spectra of neutrons, protons, deuterons, tritons and alphas from the compound nuclei in the fusion reactions are calculated. It is found that the Coulomb interaction between the charged particles and daughter nuclei dominates the kinetic energy spectra and leads to the Boltzmann distribution. The $\alpha$ yields are comparable with the hydrogen isotopes and have the same order of magnitude. The shell effect is of significance on the fusion-evaporation cross sections and particle energy spectra.

This study isolated a compound with anti-inflammatory properties from Musa × paradisiaca fruit peels. The methanol extract was partitioned, and the hexane fraction with the best bioactivity was subjected to column chromatography before characterization via Fourier transform infrared (FTIR), UV-visible (UV-VIS) and NMR analysis. The in vivo anti-inflammatory properties of the methanol extract and hexane fraction were investigated using the formalin-induced oedema model in rats. The compound's antioxidant, red blood cell (RBC) membrane stabilization and phospholipase-A2 (PL-A2) inhibitory effects were evaluated in vitro. The UV-VIS spectrum at 222nm absorbance and FTIR absorption at 2922, 2855, 1707, 1643, 1453 and 1375cm-1 with proton and carbon-13 spectra suggest the compound is a steroid. The in vivo anti-inflammatory assay showed significant oedema reduction of the hexane fraction at 200mg/kg. The compound also displayed Fe3+ reduction and scavenged free radical molecules while showing PL-A2 inhibition and the ability to limit RBC haemolysis. The compound also presented stronger affinities for PL-A2 (-7.6kcal/mol) and NF-κB (-6.0kcal/mol) than indomethacin and ibuprofen drugs, with a favourable pharmacokinetic model. Though M. × paradisiaca fruit peels are often discarded as waste, our study highlights a sustainable approach to the reutilization of this plant material as a source of a lead molecule for inflammatory disease management.

Abstract The Parker Solar Probe Integrated Science Investigation of the Sun (IS⊙IS) instrument suite measured a variety of suprathermal and energetic particle events during orbits 18 and 19. We provide an overview of key features of the observations to provide guidance critical to making progress on complicated, integrated data sets like those provided by IS⊙IS. In this work, we analyze and describe observations of particle acceleration signatures associated with coronal mass ejection (CME)–driven shocks and solar flares from 2023 November to 2024 March as measured by the IS⊙IS/Energetic Particle Instrument-Low Energy and Energetic Particle Instrument-High Energy particle detectors. We present energy spectra for protons through Fe ions from ∼10 keV nuc −1 to >10 MeV nuc −1 , abundance ratios, and time series analyses for seven solar energetic particle (SEP) events with respect to the magnetic field and plasma context provided by the FIELDS and Solar Wind Electrons Alphas and Protons instruments, respectively. For SEP events in orbits 18 and 19, we find that acceleration driven by multiple CMEs in succession have larger variability in 4 He/H and Fe/O ratios than singular CMEs, that flare-associated SEP events preferentially accelerate higher mass-to-charge ratio particles, and that shock upstream transients may be present in CME-driven interplanetary shocks.

Abstract This study explores the acceleration origins of solar energetic particles (SEPs) by analyzing the energy spectral characteristics of particles in ground-level enhancement (GLE) events and common SEP (non-GLE) events, as well as the correlations of the peak intensities of energetic particles with flare and coronal mass ejection (CME) diagnostic parameters. By examining the peak energy spectra of protons, for protons with energies >66 MeV, the peak intensities in most GLE events are significantly higher than those in SEP events, establishing an energy threshold distinguishing GLE from non-GLE events. Given the strong correlation between energetic electrons and protons, radio bursts and soft X-rays (SXRs) produced by energetic electrons can be used to study acceleration regions of GLE. Based on data from solar cycles 23 and 24, multifrequency radio data (5, 8.8, and 15.4 GHz) and SXR intensity analysis reveal the heights of particle acceleration. The results indicate that protons with energies >66 MeV in GLE events are closely associated with flare-related acceleration in the low corona, although a contribution from CME-driven shock acceleration cannot be excluded. In contrast, lower-energy protons (<10 MeV) are primarily accelerated by CME-driven shocks. Moreover, SEPs at intermediate energies exhibit a mixed origin, which includes particles accelerated by both flares and CME-driven shocks. These findings provide key insights into the mechanisms of particle acceleration in solar events.

Application of NMR to Large RNAs.

Precise measurements of the cosmic ray proton energy spectrum in the "knee" region.

NUSES is a pathfinder satellite that will be deployed in a low Earth orbit, designed with new technologies for space-based detectors. Ziré is one of the payloads of NUSES and aims to measure the spectra of electrons, protons, and light nuclei in a kinetic energy range spanning from a few MeVs to several hundred MeVs, as well as photons in the energy range from 0.1 MeV to 30 MeV. Ziré consists of a Fiber TracKer (FTK), a Plastic Scintillator Tower (PST), a calorimeter (CALOg), an AntiCoincidence System (ACS) and a Low Energy Module (LEM). The FTK is based on thin scintillating fibers read out by Silicon Photomultiplier (SiPM) arrays. We assembled a prototype of Ziré (Zirettino) equipped with a single FTK layer, a reduced number of PST layers and a partially instrumented CALOg. A preliminary version of the Ziré custom Front-End Board (FEB) featuring the on-the-shelf ASIC CITIROC by OMEGA/Weeroc was used for the readout. We carried out several beam test campaigns at CERN’s PS facility and a dynamic qualification test. The performance of FTK will be presented and discussed.

Abstract Blazars launch relativistic jets aligned with our line of sight, resulting in extreme beaming and making them among the most luminous extragalactic sources across the electromagnetic spectrum, from radio to γ-rays and potentially high-energy neutrinos. We present a comprehensive study of multi-messenger emission from blazar jets powered by magnetic reconnection at varying distances from the supermassive black hole (SMBH). By generalizing previous models, we track the spatial evolution of key jet properties, including magnetization, bulk Lorentz factor, and external photon fields (accretion disc, broad-line region, dusty torus), and compute self-consistently the resulting broadband photon spectra and neutrino emission. Our numerical simulations explore how the initial jet magnetization, particle acceleration efficiency, jet-to-accretion-power ratio, and accretion rate impact emission. We identify distinct regimes: synchrotron and synchrotron self-Compton dominate closer to the SMBH, where magnetization is high, while external Compton becomes significant near the BLR. Neutrino production is most efficient upstream of the BLR, driven by enhanced target photon densities and hard proton spectra. Our model predictions are then compared with observations of γ-ray luminosities and synchrotron peak energies of Fermi-detected blazars, highlighting magnetic reconnection as a viable mechanism for electromagnetic and neutrino emissions in astrophysical jets. Crucially, our framework assumes equal injected luminosities of pairs and protons, thereby limiting baryon loading. While our model successfully reproduces the photon emission of extreme blazars such as 3HSP J095507.9+355101, it cannot self-consistently account for TXS-like flares, which would require extremely high baryon loading.

Abstract Local particle acceleration in the shock sheath region formed during the interaction between multiple coronal mass ejections (CMEs) is a complicated process that is still under investigation. On 2024 March 23, the successive eruption of two magnetic flux ropes from the solar active region 3614 produced twin CMEs, as identified in coronagraph images. By analyzing in situ data from Solar Orbiter and Wind, it is found that the primary interplanetary CME (ICME)-driven shock overtook the preceding ICME, trapping it in the sheath between the shock and the primary ICME, forming the ICME-in-sheath (IIS) structure. Using Solar Orbiter observations, we show that both electrons and ions are accelerated within the IIS. A clear enhancement of suprathermal electrons was observed at the IIS boundary, where strong flow shear and large magnetic field variation suggest possible local electron acceleration. Electrons (>38 keV) exhibit a long-lasting enhancement in the IIS with a spectral index of ∼2.2, similar to that in the shock sheath and the primary ICME, indicating a similar solar origin. Inside both the sheath and IIS, spectra of protons and 4 He are generally consistent with the prediction of the diffusive shock acceleration, whereas Fe and O present a double power-law shape. Additionally, the Fe/O ratio in the IIS is higher than that in the sheath, and closer to the abundance of the flare-related particles, suggesting the remnant particles of flare confined in the IIS.

Abstract Almost three thousand daily AMS‐02 proton spectra from 2011 to 2019 offer the most precise and extensive data set of cosmic ray spectra covering a wide energy range. As such, they offer a unique opportunity to test machine learning algorithms for approximating cosmic ray proton spectra based on the inputs usually available to solar modulation models. We evaluated how various machine learning techniques approximate the temporal evolution of the AMS‐02 flux for a wide range of published rigidity bins from 2011 to 2019, primarily focusing on the feasibility and effectiveness of machine learning approaches compared to the traditional force field model in approximating cosmic ray proton spectra. The machine learning methods are very accurate, particularly in comparison to the established force field approach, and significantly improve the approximation of the behavior of cosmic rays.

Numerous astrophysical shock waves evolve in an environment where the radiative cooling behind the shock affects the hydrodynamical structure downstream, thereby influencing the potential for particle acceleration via diffusive shock acceleration (DSA). We study the possibility for DSA to energize particles from the thermal pool and from preexisting cosmic rays at radiative shocks, focusing on the case of supernova remnants (SNRs). We relied on a semi-analytical description of particle acceleration at collisionless shocks in the test-particle limit, estimating the particle spectrum, maximum energy, and total proton and electron content expected from SNRs throughout the radiative phase. Our results indicate that DSA at radiative shocks can lead to significant particle acceleration during the first few tens of kiloyears of the radiative phase. Although the associated multiwavelength emission from SNRs in the radiative phase may not be detectable with current observatories in most cases, the radiative phase is found to lead to substantial deviations from the canonical p^-4 of the test-particle limit. The hardening and/or steepening is due to an interplay between a growing contribution of the reaccelerated term as the SNR volume expands and the effects of adiabatic and radiative losses on trapped particles as particles are confined for a longer time. The slope of the cumulative proton and electron spectra over the SNR lifetime thus depends on the environment in which the SNR shock propagates, and on the duration of the radiative phase during which DSA can take place. Overall, DSA in the radiative phase can lead to a total electron spectrum steeper than the proton spectrum, both at SNRs from thermonuclear and core--collapse SNe. Finally, we comment on the case of young radiative SNRs (in the first month to a few years after the explosion) for which the denser environments (with mass-loss rates of dot M ∼ 10^ - 1 M_⊙/yr) tend to inhibit DSA.

Methylidyne (CH) has long been considered a reliable tracer of molecular gas in the low-to-intermediate extinction range. Although extended CH 3.3 GHz emission is commonly observed in diffuse and translucent clouds, observations in cold, dense clumps are rare. In this work, we conducted high-sensitivity CH observations toward 27 Planck Galactic cold clumps (PGCCs) with the Arecibo 305 m telescope. Toward each source, the CH data were analyzed in conjunction with 13 CO (1–0) emission, H I narrow self-absorption (HINSA), and H 2 column densities inferred from thermal dust emission. Our results reveal ubiquitous subsonic velocity dispersions of CH, in contrast to 13 CO, which is predominantly supersonic. The findings suggest that subsonic CH emissions may trace dense, low-turbulent gas structures in PGCCs. To investigate how environmental parameters, particularly the cosmic-ray ionization rate (CRIR), affect the evolution of CH in PGCCs, we estimated upper limits for the CRIR using HINSA. The derived values span (8.1 ± 4.7) × 10 −18 to (2.0 ± 0.8) × 10 −16 s −1 over an H 2 column density range of (1.7 ± 0.2) × 10 21 to (3.6 ± 0.4) × 10 22 cm −2 . This result favors theoretical predictions of a cosmic-ray attenuation model, in which the interstellar spectra of low-energy CR protons and electrons match Voyager measurements, although alternative models cannot yet be ruled out. The abundance of CH decreases with increasing column density, while showing a positive dependence on the CRIR, which requires atomic oxygen not heavily depleted to dominate CH destruction in PGCCs. By fitting the abundance of CH with an analytic formula, we placed constraints on atomic O abundance (2.4 ± 0.4 × 10 −4 with respect to H column density) and C + abundance (7.4 ± 0.7 × 10 13 ζ 2 / n H 2 ). These findings indicate that CH formation is closely linked to the C + abundance, regulated by cosmic-ray ionization, while other processes, such as turbulent diffusive transport, might also contribute a non-negligible effect to CH formation.

A dosimetric and biological model for neutron capture therapy (NCT) experiments.

A thermal model describing hadron production in heavy-ion collisions in the few-GeV energy regime is combined with the concept of nucleon coalescence to make predictions for the production of 3H and 3He nuclei. A realistic parametrization of the freeze-out conditions is employed, which accurately reproduces the spectra of protons and pions. It also correctly predicts the deuteron yield, which agrees with experimental observations. However, the predicted yields of 3H and 3He are lower than the experimental results by approximately a factor of two. The model predictions for the spectra can be compared with future experimental data.

Event shape measurements are crucial for understanding the underlying event and multiple-parton interactions (MPIs) in high energy proton-proton (pp) collisions. In this study, the Tsallis blast-wave model with independent non-extensive parameters for mesons and baryons was applied to analyze the transverse momentum spectra of charged pions, kaons, and protons in pp collision events at TeV classified by event shape estimators such as relative transverse event activity, unweighted transverse spherocity, and flattenicity. Our analysis reveals consistent trends in the kinetic freeze-out temperature and non-extensive parameter across different collision systems and event shape classes. The use of diverse event-shape observables in pp collisions has significantly expanded the accessible freeze-out parameter space, enabling a more comprehensive exploration of its boundaries. Among these event shape classifiers, flattenicity emerges as a unique observable for disentangling hard process contributions from additive MPI effects, which helps isolate collective motion effects encoded by the radial flow velocity. Through the analysis of the interplay between event-shape measurements and kinetic freeze-out properties, we gain deeper insights into mechanisms responsible for flow-like signatures in pp collisions.

We report on the development of a robust microfluidic nozzle capable of generating replenishing liquid sheet targets with sub-micron thickness at up to kHz repetition rates, a λ/20 surface flatness over areas of at least 100μm2, and in-vacuum dimensions of 6 × 1.5mm2. The platform was evaluated for stability under hundreds of 4.3J laser shots at 0.5Hz and 6 × 1020 W/cm2 peak intensity, delivered in burst mode, totaling 2.9 kJ on the target. The key metrics of the platform, including sheet characteristics, nozzle aperture morphology, and proton spectra, showed no measurable degradation in the performance of the liquid sheet platform following this experiment. Beyond its application to ion beam technology, we outline a pathway to further develop the capabilities of the platform into a high-repetition-rate plasma mirror.

Abstract Active galactic nuclei (AGN) can accelerate protons to energies of ∼10–100 TeV, with secondary production of high-energy neutrinos. If the acceleration is driven by magnetized turbulence, the main properties of the resulting proton and neutrino spectra can be deduced based on insights from particle-in-cell simulations of magnetized turbulence. We have previously shown that these properties are consistent with the TeV neutrino signal observed from the nearby active galaxy NGC 1068. In this work, we extend this result to a population study. We show that the produced neutrino flux depends mainly on the energetics of the corona—the relative fractions of X-ray, magnetic, and nonthermal proton energy—and on the spectral energy distribution of the AGN. We find that coronae with similar properties can explain neutrinos from the candidate AGN for which IceCube has reported an excess, albeit less significant than NGC 1068. Building on this framework, we show how the neutrino signal evolves with AGN luminosity, and use this AGN sequence to predict the diffuse neutrino flux from the extragalactic population, showing that it can account for the diffuse neutrino signal observed by IceCube in the ∼1–100 TeV energy range.

ABSTRACT We perform the first direct consistency check between the recently measured proton spectrum at the knee by Large High Altitude Air Shower Observatory (LHAASO) and the collaboration’s own high-precision mapping of Galactic diffuse gamma-ray emission. By modelling the hadronic gamma-ray production using the updated cosmic-ray spectra, gas templates, and cross-section models, we show that the predicted gamma-ray flux robustly overshoots the LHAASO data in both inner and lateral Galactic regions. This persistent mismatch in both normalization and spectral shape challenges conventional scenarios linking the local cosmic-ray sea to Galactic gamma-ray emission, and calls for a revision of current cosmic ray models in the TeV–PeV sky.

The study involved the formation of several new mercury complexes by reacting 2-thiouracil with mercury chloride and sodium hydroxide to yield the mercury complex L1. This reaction was considered the basis for preparing other complexes, as it reacts with two moles of triphenylphosphine (PPh3) to form complex L2, and through the reaction of complex L1 with bis(diphenylphosphanyl)methane (dppm) to create complex L3, and with 1,2-bis(diphenylphosphanyl)ethane (dppe) to form complex L4, and with 1,3-bis(diphenylphosphanyl)propane (dppp) to form complex L5. The validity of the prepared complexes was confirmed through spectral measurements, including the infrared spectrum and the proton and phosphorus nuclear magnetic resonance spectra. The presence of new bands in the infrared spectrum, such as the (Hg-N) and (Hg-O) bands, provided evidence of a bond. Mercury with thiouracil as between the bands belonging to (P-Ph) and (C-P), proof of the association of phosphine with the metal, and between the 1H-NMR spectrum, there are signals belonging to the benzene ring in phosphine, and this was confirmed by their complements, which were identical to the protons of the benzene rings. Between the 31P-NMR spectrum, there is a single signal indicating that the association is double in phosphine with the presence of one isomer of the complexes. The effectiveness of the prepared complexes was tested on two types of bacteria, positive and negative, using the antibiotic amoxicillin as a control sample. The confounders showed a direct relationship with the concentration, and the L2 complex showed the highest effectiveness against the two types of bacteria studied.