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This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21–23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9–10, 2012 Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). The white paper is furthermore informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12–13, 2014. In summary we find that nuclear astrophysics is a modern and vibrant field addressing fundamental science questions at the intersection of nuclear physics and astrophysics. These questions relate to the origin of the elements, the nuclear engines that drive life and death of stars, and the properties of dense matter. A broad range of nuclear accelerator facilities, astronomical observatories, theory efforts, and computational capabilities are needed. With the developments outlined in this white paper, answers to long standing key questions are well within reach in the coming decade. [ABSTRACT FROM AUTHOR]

In this paper, we deal with the historical origins of Fermi–Dirac statistics, focusing on the contribution by Enrico Fermi of 1926. We argue that this statistics, as opposed to that of Bose–Einstein, has been somewhat overlooked in the usual accounts of the old quantum theory. Our main objective is to offer a critical analysis of Fermi's seminal paper and its immediate impact. Secondly, we are also interested in assessing the status of the particle concept in the years 1926–1927, especially regarding the germ of quantum indistinguishability. We will see, for example, that the first applications of the Fermi–Dirac statistics to the study of metals or stellar matter had a technical nature, and that their main instigators barely touched upon interpretative matters. Finally, we will discuss the reflections and remarks made in these respects in two famous events in physics of 1927, the Como conference and the fifth Solvay congress. [ABSTRACT FROM AUTHOR]

Copyright of University Chemistry is the property of Peking University, College of Chemistry & Molecular Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we revisit metal-enriched rotating pair-instability supernovae (PISNe) models for metallicities consistent with the Small Magellanic Cloud, the Large Magellanic Cloud (LMC), and 0.1 Z ⊙. By calculating multiple models, we intend to clarify mass ranges and the ejected 56Ni masses from the PISNe, and mass-loss histories for progenitors. We find that the choice of the Wolf–Rayet (WR) mass-loss rates is important, and we adopt the recently proposed rate of Sander & Vink, which covers the mass ranges for PISNe progenitors. We show that slow rotation lowers the PISN range because the core mass increases by rotational mixing. On the other hand, when we assume a typical rotation speed for observed OB stars, the mass-loss increase becomes more significant, and the final stellar masses are lower than in nonrotating models. As a result, the typical mass range for bright supernovae (SNe), with a 56Ni mass higher than 10 M ⊙ for these fast-rotating models is more than 400 and 350 M ⊙ for LMC and 0.1 Z ⊙ metallicities, respectively. It is interesting that unlike in previous works, we find oxygen-rich progenitors for most cases. This O-rich progenitor may be consistent with the recently identified PISN candidate SN2018ibb. He-rich progenitors are seen only for relatively dim and metal-poor (Z ≲ 0.1 Z ⊙) PISNe. We also discuss the black hole mass gap for metal-enriched PISNe, and we show that the upper bound for the gap is lower than in the Population III case. [ABSTRACT FROM AUTHOR]

This document is a special issue of the journal "Symmetry" titled "Symmetry beyond the Standard Models of Cosmology, High Energy Physics and Quantum Field Theory." It discusses the advancements in research on the nature of matter, particularly at high interaction energies that are inaccessible on Earth. The study of phenomena beyond the standard model is explored through the interdependent paths of cosmology, high-energy physics, and quantum field theory. The papers in this special issue cover a range of topics, including the spin-charge-family theory, gravitational baryogenesis, the evolution of the universe, dark matter, primordial black holes, primordial nucleosynthesis, and new types of particles. The document concludes by highlighting the exciting advances in the study of symmetry groups and macroscopic structures. [Extracted from the article]

The chemical composition of the shell of a neutron star (SNS) at high temperatures and densities is discussed in this paper. A model for nucleosynthesis is proposed based on the approximation of nuclear statistical equilibrium (NSE). The dependence of the results of the nucleosynthesis on the parameters of the medium in a static approximation is studied. The results of this paper are qualitatively similar to earlier work by other authors. It is shown that the proposed model provides a fair description of the abundance of nuclei even in the static approximation. [ABSTRACT FROM AUTHOR]

The article offers the author's insights on the significance of the study of Ralph Alpher, George Gamow, and Hans Bethe on precision cosmology despite its incorrect concept of nucleosynthesis by neutron capture. The author states that Gamow's Big Bang nucleosynthesis (BBN) has led to forecasting of relic thermal radiation which is the cosmic microwave background (CMB). He also says that the group was right in determining the existence of CMB and significance of nuclear physics in the universe.

JET experiments using the fuel mixture envisaged for fusion power plants, deuterium and tritium (D–T), provide a unique opportunity to validate existing D–T fusion power prediction capabilities in support of future device design and operation preparation. The 2021 JET D–T experimental campaign has achieved D–T fusion powers sustained over 5 s in ITER-relevant conditions i.e. operation with the baseline or hybrid scenario in the full metallic wall. In preparation of the 2021 JET D–T experimental campaign, extensive D–T predictive modelling was carried out with several assumptions based on D discharges. To improve the validity of ITER D–T predictive modelling in the future, it is important to use the input data measured from 2021 JET D–T discharges in the present core predictive modelling, and to specify the accuracy of the D–T fusion power prediction in comparison with the experiments. This paper reports on the validation of the core integrated modelling with TRANSP, JINTRAC, and ETS coupled with a quasilinear turbulent transport model (Trapped Gyro Landau Fluid or QualLiKiz) against the measured data in 2021 JET D–T discharges. Detailed simulation settings and the heating and transport models used are described. The D–T fusion power calculated with the interpretive TRANSP runs for 38 D–T discharges (12 baseline and 26 hybrid discharges) reproduced the measured values within 20 %. This indicates the additional uncertainties, that could result from the measurement error bars in kinetic profiles, impurity contents and neutron rates, and also from the beam-thermal fusion reaction modelling, are less than 20 % in total. The good statistical agreement confirms that we have the capability to accurately calculate the D–T fusion power if correct kinetic profiles are predicted, and indicates that any larger deviation of the D–T fusion power prediction from the measured fusion power could be attributed to the deviation of the predicted kinetic profiles from the measured kinetic profiles in these plasma scenarios. Without any posterior adjustment of the simulation settings, the ratio of predicted D–T fusion power to the measured fusion power was found as 65%–96% for the D–T baseline and 81%–97% for D–T hybrid discharge. Possible reasons for the lower D–T prediction are discussed and future works to improve the fusion power prediction capability are suggested. The D–T predictive modelling results have also been compared to the predictive modelling of the counterpart D discharges, where the key engineering parameters are similar. Features in the predicted kinetic profiles of D–T discharges such as underprediction of ne are also found in the prediction results of the counterpart D discharges, and it leads to similar levels of the normalized neutron rate prediction between the modelling results of D–T and the counterpart D discharges. This implies that the credibility of D–T fusion power prediction could be a priori estimated by the prediction quality of the preparatory D discharges, which will be attempted before actual D–T experiments. [ABSTRACT FROM AUTHOR]

The nucleosynthesis of chemical elements has been established to be the result of a variety of different types of nuclear reactions in stars. Under the extreme temperatures and densities encountered in such environments, nuclear isomers can be populated and thus complicate our understanding of these processes. In this paper, I have chosen to discuss five cases that illustrate how nuclear isomers can play important roles in the nucleosynthesis of chemical elements. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the neutrino-driven winds that emerge in 12 unprecedentedly long-duration 3D core-collapse supernova simulations done using the code F ornax. The 12 models cover progenitors with zero-age main-sequence mass between 9 and 60 solar masses. In all our models, we see transonic outflows that are at least 2 times as fast as the surrounding ejecta and that originate generically from a proto−neutron star surface atmosphere that is turbulent and rotating. We find that winds are common features of 3D simulations, even if there is anisotropic early infall. We find that the basic dynamical properties of 3D winds behave qualitatively similarly to those inferred in the past using simpler 1D models, but that the shape of the emergent wind can be deformed, very aspherical, and channeled by its environment. The thermal properties of winds for less massive progenitors very approximately recapitulate the 1D stationary solutions, while for more massive progenitors they deviate significantly owing to aspherical accretion. The Y e temporal evolution in winds is stochastic, and there can be some neutron-rich phases. Though no strong r -process is seen in any model, a weak r -process can be produced, and isotopes up to 90Zr are synthesized in some models. Finally, we find that there is at most a few percent of a solar mass in the integrated wind component, while the energy carried by the wind itself can be as much as 10%–20% of the total explosion energy. [ABSTRACT FROM AUTHOR]

We study the coupling of hydrodynamics and reactions in simulations of the double-detonation model for Type Ia supernovae. When assessing the convergence of simulations, the focus is usually on spatial resolution; however, the method of coupling the physics together as well as the tolerances used in integrating a reaction network also play an important role. In this paper, we explore how the choices made in both coupling and integrating the reaction portion of a simulation (operator/Strang splitting versus the simplified spectral deferred corrections method we introduced previously) influences the accuracy, efficiency, and nucleosynthesis of simulations of double detonations. We find no need to limit reaction rates or reduce the simulation time step to the reaction timescale. The entire simulation methodology used here is GPU-accelerated and made freely available as part of the Castro simulation code. [ABSTRACT FROM AUTHOR]

The article focuses on investigating two concepts, namely the country of origin effect and consumer ethnocentrism. The main goal of the article is 1) to investigate the current state of the level of consumer ethnocentrism in the cohort of young Slovaks; 2) to investigate the current state of the perceived preference of Slovaks or of foreign products in the youth cohort; and 3) to investigate the relationship between elements of country of origin effects on food products and the level of consumer ethnocentrism. As part of the methodological procedure, we demonstrate the feasibility and validity of the tool. In the paper, we use several elements of descriptive statistics, based on which we evaluate a primary survey. The results indicate a below-average level of consumer ethnocentrism. We identify preferences in the context of the country of origin. It is also possible to establish a link between the country of origin effect and consumer ethnocentrism, albeit at a lower level. [ABSTRACT FROM AUTHOR]

Just over 100 years ago, Henry Moseley carried out a systematic series of experiments which showed that the frequencies of the X-rays emitted from an elemental target under bombardment by cathode rays were characteristic of that element and could be used to identify the charge on its atomic nucleus. This led to a reorganization of the periodic table, with chemical elements now arranged on the basis of atomic number Z rather than atomic weight A, as had been the case in previous tables, including those developed by Mendeleev. Moseley also showed that there were four 'missing elements' before gold. With further measurements up to uranium Z=92, the Swedish physicist Manne Siegbahn identified two more missing elements. This paper provides an introduction to Moseley and his experiments and then traces attempts to 'discover' missing elements by X-ray spectroscopy. There were two successes with hafnium (Z=72) and rhenium (Z=75), but many blind alleys and episodes of self-deception when dealing with elements 43, 61, 85 and 87. These all turned out to be radioactive, with extremely small natural abundances: all required synthesis by a nuclear reaction, with radiological characterization in the first instance. Finally, the paper moves on to consider the role of X-ray spectroscopy in exploring the periodic table beyond uranium. Although the discovery of artificial radioactive elements with Z>92 again depended on nucleosynthesis and radiological characterization, measurement of the frequencies or energies of characteristic X-rays remains the ultimate goal in proving the existence of an element. [ABSTRACT FROM AUTHOR]

Copyright of Gerion: Revista de Historia Antigua is the property of Universidad Complutense de Madrid and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The neutrino-driven wind cooling phase of proto-neutron stars (PNSs) follows successful supernovae. Wind models without magnetic fields or rotation fail to achieve the necessary conditions for production of the third r -process peak, but robustly produce a weak r- process in neutron-rich winds. Using 2D magnetohydrodynamic simulations with magnetar-strength magnetic fields and rotation, we show that the PNS rotation rate significantly affects the thermodynamic conditions of the wind. We show that high-entropy material is quasiperiodically ejected from the closed zone of the PNS magnetosphere with the required thermodynamic conditions to produce heavy elements. We show that maximum entropy S of the material ejected depends systematically on the magnetar spin period P ⋆ and scales as S ∝ P ⋆ − 5 / 6 for sufficiently rapid rotation. We present results from simulations at a constant neutrino luminosity representative of ∼1–2 s after the onset of cooling for P ⋆ ranging from 5–200 ms and a few simulations with evolving neutrino luminosity where we follow the evolution of the magnetar wind until 10–14 s after the onset of cooling. We estimate at magnetar polar magnetic field strength B 0 = 3 × 1015 G and 1015 G that neutron-rich magnetar winds can, respectively, produce at least ∼1–5 × 10−5 M ⊙ and ∼1–4 × 10−7 M ⊙ of material with the required parameters for synthesis of the third r -process peak, within 1–2 s and 10 s, respectively, in that order after the onset of cooling. We show that proton-rich magnetar winds can have favorable conditions for production of p- nuclei, even at a modest B 0 = 5 × 1014 G. [ABSTRACT FROM AUTHOR]

Strong metallicity-dependent winds dominate the evolution of core He-burning, classical Wolf–Rayet (cWR) stars, which eject both H and He-fusion products such as |$^{14}$| N, |$^{12}$| C, |$^{16}$| O, |$^{19}$| F, |$^{22}$| Ne, and |$^{23}$| Na during their evolution. The chemical enrichment from cWRs can be significant. cWR stars are also key sources for neutron production relevant for the weak s-process. We calculate stellar models of cWRs at solar metallicity for a range of initial Helium star masses (12–50  |$\rm M_{\odot }$|⁠), adopting recent hydrodynamical wind rates. Stellar wind yields are provided for the entire post-main sequence evolution until core O-exhaustion. While literature has previously considered cWRs as a viable source of the radioisotope |$^{26}$| Al, we confirm that negligible |$^{26}$| Al is ejected by cWRs since it has decayed to |$^{26}$| Mg or proton-captured to |$^{27}$| Al. However, in Paper I, we showed that very massive stars eject substantial quantities of |$^{26}$| Al, among other elements including N, Ne, and Na, already from the zero-age-main-sequence. Here, we examine the production of |$^{19}$| F and find that even with lower mass-loss rates than previous studies, our cWR models still eject substantial amounts of |$^{19}$| F. We provide central neutron densities (N |$_{n}$|⁠) of a 30  |$\rm M_{\odot }$| cWR compared with a 32  |$\rm M_{\odot }$| post-VMS WR and confirm that during core He-burning, cWRs produce a significant number of neutrons for the weak s-process via the |$^{22}$| Ne(⁠|$\alpha$|⁠ ,n) |$^{25}$| Mg reaction. Finally, we compare our cWR models with observed [Ne/He], [C/He], and [O/He] ratios of Galactic WC and WO stars. [ABSTRACT FROM AUTHOR]

The paper is concerned with the identification of the key mechanisms controlling deflagration-to-detonation transition in a stellar medium. The issue of thermal runaway triggered by positive feedback between the advancing flame and the flame-driven precompression is discussed in the framework of a one-dimensional flame-folding model. The paper is an extension of the authors' previous study dealing with the non-stoichiometric fusion, f u e l → p r o d u c t s , kinetics (Phys.Rev.E, 103(2021)) over physically more relevant, f u e l + f u e l → p r o d u c t s , kinetics. Despite this change the runaway effect endures. The mean velocity ⟨ D f ⟩ of the pretransition flame does not reach the threshold of Chapman–Jouguet deflagration. [ABSTRACT FROM AUTHOR]

Nowadays, nanotechnology offers opportunities to create new features and functions of emerging materials. Correlation studies of nanostructured materials' development processes with morphology, structure, and properties represent one of the most important topics today due to potential applications in all fields: chemistry, mechanics, electronics, optics, medicine, food, or defense. Our research was motivated by the fact that in the nanometric domain, the crystalline structure and morphology are determined by the elaboration mechanism. The objective of this paper is to provide an introduction to the fundamentals of nanotechnology and nanopowder production using the sun's energy. Solar energy, as part of renewable energy sources, is one of the sources that remain to be exploited in the future. The basic principle involved in the production of nanopowders consists of the use of a solar energy reactor concentrated on sintered targets made of commercial micropowders. As part of our study, for the first time, we report the solar ablation synthesis and characterization of Ni-doped ZnO performed in the CNRS-PROMES laboratory, UPR 8521, a member of the CNRS (French National Centre for Scientific Research). Also, we study the effect of the elaboration method on structural and morphological characteristics of pure and doped ZnO nanoparticles determined by XRD, SEM, and UV-Vis. [ABSTRACT FROM AUTHOR]

Long-lived massive magnetars are expected to be remnants of some binary neutron star (BNS) mergers. In this paper, we argue that the magnetic powered flaring activities of these merged magnetars would occur dominantly in their early millisecond-period-spin phase, which is in the timescale of days. Such flares endure significant absorption by the ejecta from the BNS collision, and their detectable energy range is from 0.1 to 10 MeV, in a time lag of approximately days after the merger events indicated by the gravitational wave chirps. We estimate the rate of such flares in different energy ranges, and find that there could have been 0.1–10 cases detected by Fermi/GBM. A careful search for ∼10 ms spin-period modulation in weak short gamma-ray bursts (GRBs) may identify them from the archival data. The next-generation megaelectronvolt detectors could detect them at a mildly higher rate. The recent report on the Quasi-Period-Oscillation found in two BASTE GRBs should not be considered as cases of such flares, for they were detected in a lower energy range and with a much shorter period spin modulation. [ABSTRACT FROM AUTHOR]

The paper presents the importance of mineral deposit modeling, based on the elucidation of key elements of its origin, for the development of reliable criteria for prospecting of new deposits and orebodies of this type. On the example of the Kremikovtsi carbonate-hosted IF-barite-polymetallic deposit, it is shown that the adoption of a wellgrounded syngenetic or epigenetic concept for its origin is crucial for successful prospecting activity. Based on the developed model for a sedimentary-exhalative (SEDEX) origin of the deposit (i.e. syngenetic to the carbonate host), the key factors controlling ore formation are specified, and an optimal strategy for future prospecting in the region is proposed. [ABSTRACT FROM AUTHOR]

This paper summarizes recent work on the possible gravitational-wave signal from binary neutron-star mergers in which there is a crossover transition to quark matter. Although this is a small piece of a much more complicated problem, we discuss how the power spectral density function may reveal the presence of a crossover transition to quark matter. [ABSTRACT FROM AUTHOR]

This volume publishes materials of the International Conference ( I Humboldt- Kolleg i ) "Contact zones of Europe from the 3rd mill. Questions were raised about what types of contact zones are actually distinguished ("physical" and "social"), about the conceptual difference between the concepts of "contact zone" and "border area". The material culture of the Sarmatian tribes changed in this contact zone over several generations, as they found themselves in a completely new political and geographical environment, separated from their steppe relatives. Heinrich Härke demonstrated in the paper "Conquest, conflict, and co-existence: Multiple monocultures and dual contact zones in the British Isles, 5th-8th centuries AD" that the borders associated with early medieval migrations in Europe did not always turn into contact zones, as might be expected. [Extracted from the article]

Sensitivity studies conducted in this paper aim to examine the influence of uncertainties in beta decay rates on simulations of rapid neutron capture (r-process) nucleosynthesis. However, previous studies multiplied the ground states of the theoretical rates or the ground states of the experimental rates by 10, and most of the theoretical rates and the experimental rates consider only the beta decay rates of the ground states but not the rates in stellar conditions because of the thermally excited states. In this study, we performed the first sensitivity test on the excited states of nuclei having A > 120 in the r-process. The ground state beta decay rates and estimated excited state rates are folded together to estimate a thermal decay rate as a function of temperature. We examined how the thermally excited states affect the stellar rates for all A > 120 nuclei. We found that there is a slight change in the second peak of final abundance in the r-process by Lu isotopes. This is the same as that in Famiano's paper (Famiano and Boyd 2008 J. Phys. G: Nucl. Part. Phys. 35 2). [ABSTRACT FROM AUTHOR]

Observations of the kilonova from the neutron star merger event GW170817 opened a way to study r -process nucleosynthesis directly using neutron star mergers. It is, however, challenging to identify individual elements in kilonova spectra due to a lack of complete atomic data, in particular at near-infrared (NIR) wavelengths. In this paper, we demonstrate that spectra of chemically peculiar stars with enhanced heavy-element abundances can provide us with an excellent astrophysical laboratory for kilonova spectra. We show that the photosphere of the late B-type, chemically peculiar star HR 465 has similar lanthanide abundances and ionization degrees with those in the line-forming region in a kilonova at ∼2.5 days after the merger. The NIR spectrum of HR 465 taken with Subaru/IRD indicates that Ce iii lines give the strongest absorption feature around 16000 Å and there are no other comparably strong transitions around these lines. The Ce iii lines nicely match with the broad absorption feature at 14500 Å observed in GW170817 with a blueshift of v = 0.1 c, which supports recent identification of this feature as Ce iii by Domoto et al. [ABSTRACT FROM AUTHOR]

Mikhail Glinka represents a fundamental figure in the Russian musical culture: in traditional historiography he is considered the equivalent in music of the poet Aleksandr Pushkin as founder of original literary genres and codifier of the linguistic means with which these were expressed. For a certain period, this "parallel myth" symbolized the birth of an exclusively Russian music, a music that rejected Western influence choosing to mirror the vague concept of 'Russian soul' that he himself contributed to formulate in the years of Russian Romanticism. Today this image is subject to revisionism, oriented to highlight Glinka's synthesis of the major trends of the coeval musical language. Especially in reference to theatre, this more complex image includes elements coming from the western koiné as well as elements of Russian origin. Glinka became familiar with the Italian music tradition because this had settled in Russia during the 18th century and was still à la page during the years of Glinka's training in St Petersburg. His will to improve his compositional skills, however, led him to a prolonged stay in Italy, which made him visit several cities of the peninsula, including Rome and Naples. In his mature years, he collected the impressions of this journey in a volume of Zapiski (Memoirs, 1854). This paper investigates the effect of early-19th-century Italy on the composer as a 'Russian traveler', his own understanding of the country's culture, and the mental frame through which he could "read" the places he visited during his youth, and write about them in later times. The goal is to highlight the difference entailed by the two-stage process of reconstruction of an imaginary, in relation to the Russian context that acted as a counterpart to this gaze. [ABSTRACT FROM AUTHOR]

The cosmic origin of fluorine is still under debate. Asymptotic giant branch (AGB) stars are among the few suggested candidates to efficiently synthesis F in our Galaxy, however their relative contribution is not clear. In this paper, we briefly review the theoretical studies from stellar yield models of the F synthesis and chemical equilibrium models of the F-containing molecules in the outflow around AGB stars. Previous detections of the F-bearing species towards AGB and post-AGB stars are also highlighted. We suggest that high-resolution ALMA observations of the AlF, one of the two main carriers of F in the outflow of AGB stars, can provide a reliable tracer of the F-budget in AGB stars. This will be helpful to quantify the role of AGB stars in the Galactic F budget. [ABSTRACT FROM AUTHOR]