Developments In Nuclear Physics Research Articles

Nuclear physics – stamped

Postage stamps are not just tokens we use to send letters – they also form part of our social history. Ian Briggs looks at how developments in nuclear physics have been depicted in postage stamps.

THE PERIODIC TABLE OF CHEMICAL ELEMENTS AND THE PROBLEM OF ITS JUSTIFICATION

The article considers five stages in the history of the discovery and attempts to substantiate Mendeleev’s periodic system of chemical elements. The first stage consists in the accumulation, systematic analysis of extensive empirical material and in the direct establishment of the periodic law of chemical elements by Mendeleev. At the second stage, attempts were made to atomic-electronic explanation of the periodicity of the physical and chemical properties of elements on the basis of quantum mechanics and the Pauli principle. The third stage is associated with the development of nuclear physics, as well as with the development of such chemical methods as radiochemical analysis, the chromatographic method of color, etc. At the fourth stage, a solution to the problem was proposed on the basis of group theory in the quantum mechanical understanding. The fifth stage is based on the relational substantiation of the periodic system of chemical elements of the Mendeleev’s table, corresponding to the method of describing hadrons.

Entanglement-enhanced optical atomic clocks

Recent developments in atomic physics have enabled the experimental generation of many-body entangled states to boost the performance of quantum sensors beyond the Standard Quantum Limit (SQL). This limit is imposed by the inherent projection noise of a quantum measurement. In this Perspective article, we describe the commonly used experimental methods to create many-body entangled states to operate quantum sensors beyond the SQL. In particular, we focus on the potential of applying quantum entanglement to state-of-the-art optical atomic clocks. In addition, we present recently developed time-reversal protocols that make use of complex states with high quantum Fisher information without requiring sub-SQL measurement resolution. We discuss the prospects for reaching near-Heisenberg limited quantum metrology based on such protocols.

The British Empire’s Dr Strangelove? Ernest Titterton and the Royal Commission into British nuclear tests in Australia

This article reconsiders some of the narratives constructed by the Royal Commission into British nuclear tests in Australia (1984–85), primarily those surrounding the role of nuclear physicist Ernest Titterton. Labelled a ‘Dr Strangelove figure’ by the Royal Commission’s president, Jim McClelland, Titterton’s perceived betrayal of Australia during the nuclear tests facilitated the bolstering of nationalistic sentiment among those involved in the Commission. Problematising Titterton’s characterisation as a ‘Dr Strangelove figure’, planted in the pursuit of British interests, allows for insight into the role played by imperialism in Britain’s nuclear program, and into Australia’s contemporary history more generally. Considering nuclear testing in the context of empire demonstrates that Titterton’s appointment was in fulfilment of imperial obligations to both Britain and Australia, while his individual allegiances transcended Britain. Rather, Titterton’s allegiances lay with the promotion and development of nuclear physics, facilitated by and taking advantage of networks spanning across the Anglosphere.

Huizhou accelerator complex facility and its future development

This paper provides an overview of the frontier research fields and significant questions in nuclear physics regarding particle accelerators, and the status and future development trends for big-science facilities of particle accelerators are reviewed. Two Chinese government-approved “12th Five-Year” major science infrastructure facilities, the “High Intensity heavy-ion Accelerator Facility (HIAF)” and “China Initiative Accelerator Driven System (CiADS)”, are being constructed in Huizhou, Guangdong Province. Based on these two big-science projects (HIAF and CiADS), we proposed to establish a large-scale charged particle accelerator complex facility named the “Bright Electron and Ion research Facility (BEIF).” This facility will be dedicated to the research and development of nuclear physics and its interdisciplinary frontier fields. The research frontier fields of nuclear physics at the BEIF will include nuclear structure and astrophysics, nucleon structure, quark matter phase structure, and interdisciplinary fields between several significant frontiers of fundamental and nuclear physics, such as highly charged atomic physics and heavy ion-driven high energy density physics. BEIF will be a large-scale scientific complex facility comprising several superconducting ion LINAC accelerators, synchrotrons, storage rings, reactors, and various large experimental detectors and setups. BEIF will be built in three construction phases and will become one of the premier global large-scale particle accelerator complex facilities dedicated to the research of nuclear physics and technology.

Design and dynamic studies for a compact storage ring to generate gamma-ray light source based on Compton backscattering technique

As the development of nuclear physics and atomic sciences progresses, monochromatic and high-flux gamma-ray light sources are highly demanded by many experiments in these fields. We have designed a compact storage ring for gamma-ray source generation based on the Compton backscattering technique. The energy range of the electron beam stored in the ring will be from 500 to 800 MeV, with the capability of generating a gamma ray with an energy range from about 4 to 10 MeV. The maximum energy loss for an electron could be more than 1% for one scattering event, which could have a significant impact on electron beam dynamics. To study this impact, a 6D macroparticle tracking code has been developed by including the Compton scattering, damping, quantum excitation, and synchrotron radiation in the storage ring. The equilibrium states have been studied with this code, and the results show good agreement with theoretical predictions. The electron beam loss rate induced by Compton scattering has also been investigated by varying the input laser beam parameters. This study allows us to optimize the storage ring operation for a stable, high-flux, and narrow-bandwidth gamma-ray beam generation.

Constraining the Speed of Sound inside Neutron Stars with Chiral Effective Field Theory Interactions and Observations

Abstract The dense matter equation of state (EOS) determines neutron star (NS) structure but can be calculated reliably only up to one to two times the nuclear saturation density, using accurate many-body methods that employ nuclear interactions from chiral effective field theory constrained by scattering data. In this work, we use physically motivated ansatzes for the speed of sound c S at high density to extend microscopic calculations of neutron-rich matter to the highest densities encountered in stable NS cores. We show how existing and expected astrophysical constraints on NS masses and radii from X-ray observations can constrain the speed of sound in the NS core. We confirm earlier expectations that c S is likely to violate the conformal limit of , possibly reaching values closer to the speed of light c at a few times the nuclear saturation density, independent of the nuclear Hamiltonian. If QCD obeys the conformal limit, we conclude that the rapid increase of c S required to accommodate a 2 M ⊙ NS suggests a form of strongly interacting matter where a description in terms of nucleons will be unwieldy, even between one and two times the nuclear saturation density. For typical NSs with masses in the range of 1.2–1.4 M ⊙, we find radii between 10 and 14 km, and the smallest possible radius of a 1.4 M ⊙ NS consistent with constraints from nuclear physics and observations is 8.4 km. We also discuss how future observations could constrain the EOS and guide theoretical developments in nuclear physics.

On how Bohr model of hydrogen atom is connected to nuclear physics

Views The atom model of Quantum Mechanics (QM) was conceived from an unsolved paradox. Indeed, Schrodinger’s equation has been deducted by considering a free electron, but it is applied for the atom, where the electron is inside a potential. In order to eliminate the nonsense, quantum theorists proposed a ridiculous postulate: they claim it makes sense to use the equation because it gives results in the agreement to experimental data. The unsolved paradox evidence that Schrodinger’s equation cannot be applied to the physical conditions considered in the QM atom model, and that his equation actually requires some special conditions not considered in the theory (for instance, the electron helical trajectory, rejected by Heisenberg). The banishment of the aether has introduced several paradoxes in the development of Theoretical Physics. And because the theorists have neglected other paradox (from the mathematical probability the spectacular successes of Bohr’s hydrogen atom cannot be accidental), these two unsolved paradoxes introduced dramatic consequences in the development of Nuclear Physics.

A new trend in nuclear physics development

A new trend in nuclear physics development

BRIEF ANALYSIS OF REAL-TIME DATA COMPUTER REGISTRATION, TRANSMISSION AND PROCESSING METHODS IN NUCLEAR PHYSICS

Structural and principal problems in the field of control equipment for nuclear physics development are examined, in particular, the influence of dead time on the spectrum data aggregation and methods of correcting this influence. The variants of the organization of spectrometric systems, their advantages and disadvantages, the possibility of using different digital interfaces and computer buses are analyzed, and some of existing spectrometric equipment implementations examples are reviewed. The result of the work is an analysis of existing approaches to the equipment for electronic spectrometry organization and development, as well as a recommendation based on the approaches and different technological solutions to achieve the best ratio of performance and versatility is given. The problems that may be encountered in the spectrometric equipment development process and the existing solutions are described. The workability of various operating systems and real-time programming modules to the organization of processing equipment is examined, also the impact on the development-related cost and laboriousness of the opted facilities for solving these problems is examined, and the optimal solutions are proposed.

Розвиток ядерної фізики в Києві

Розвиток ядерної фізики в Києві

Recent Progress in Research on CsI Thin Film Photocathodes

Caesium iodide (CsI) thin films have attracted much attention due to good electron transport and emission properties in the soft X-ray and extreme ultraviolet range. With the rapid development of nuclear physics, high energy physics and astrophysics, the requirements for CsI film photocathodes become increasingly severe, and it is therefore of considerable interest to develop CsI photocathodes with high quantum efficiency (QE) and stable performance. However, the internal mechanisms of QE variation and photocathode aging are not entirely clear or certain up to date. In this paper, the recent progress on CsI film photocathodes is reviewed and some controversial issues are introduced. Several perspectives are also proposed in the end.

On Alfvén's hypothesis about nuclear hydromagnetic resonances

The atomic nucleus capability of responding by hydromagnetic vibrations, which was considered long ago by Hannes Alfvén, is re-examined in the context of current developments in nuclear physics and pulsar astrophysics.

Charged particle therapy for cancer: The inheritance of the Cavendish scientists?

The history of developments in atomic physics and its applications follows the decisive input provided by Maxwell and subsequent discoveries by his successors at the Cavendish Laboratory. In medicine the potential applications of particle physics (with the notable exception of the electron) were unfortunately delayed by the disappointing experiences with neutron therapy, which produced long-term scepticism. Neutrons are not appropriate for cancer therapy because not only their physical dose distributions offer no advantages over X-rays, but also their biological dose distributions are worse. The much improved dose distributions achieved with charged particles offer real prospects for better treatment outcomes because of the large reduction in the volume of unnecessarily irradiated tissue in many situations. Charged particle therapy is relatively new and can be applied with increasing confidence due to advances in radiology and computing, but at present there are insufficient numbers of treatment facilities to produce statistically powerful studies to compare treatment outcomes with those of X-rays. Considerable progress has been achieved in Japan and Germany with pilot studies of carbon ions but their efficacy compared with protons needs to be tested: in theory carbon should be better for intrinsically radio-resistant and for the most hypoxic tumours. The optimisation of proton and ion beam therapy in clinical practice remains to be achieved, but there are good scientific reasons why these modalities will be preferred by patients and their physicians in the future. Regrettably, despite hosting many of the momentous discoveries that enabled the development of charged particle therapy, the UK is slow to adopt and implement this very important form of cancer treatment.

Perspective on the Development of Nuclear Physics in the Past 100 Years

The course of nuclear physics is reviewed in the period from just before Hideki Yukawa's birth through the middle of the 20th century. Some information on Yukawa's first paper is presented. Then some general observations about the present state of the field of nuclear physics and of science are given.

Optical Atomic Clocks-from Dream to Reality

Recent developments in atomic physics and laser technology, especially techniques for laser cooling and the manipulation of atoms, have enabled the realization of so-called Cesium fountain atomic clocks with relative accuracy approaching 4 x 10-16.

V I Veksler and the development of nuclear physics in the Soviet Union

V I Veksler and the development of nuclear physics in the Soviet Union

THE SOLARhepPROCESS

▪ Abstract The hep process is a weak-interaction reaction, [Formula: see text], which occurs in the sun. There is renewed interest in hep owing to current experimental efforts to extract from the observed solar neutrino spectrum information on nonstandard physics in the neutrino sector. hep produces highest-energy solar neutrinos, although their flux is quite modest. This implies that the hep neutrinos can at some level influence the solar neutrino spectrum near its upper end. Therefore, a precise interpretation of the observed solar neutrino spectrum requires an accurate estimate of the hep rate. This is an interesting but challenging task. We describe the difficulties involved and how the recent theoretical developments in nuclear physics have enabled us to largely overcome these difficulties. A historical survey of hep calculations is followed by an overview of the latest developments. We compare the results obtained in the conventional nuclear physics approach and those obtained in a newly developed effective field theory approach. We also discuss the current status of the experiments relevant to hep.

The structure and spectroscopy of neutron-rich nuclei

Our knowledge of the structure and spectroscopy of neutron-rich nuclei has greatly increased due to two important developments in nuclear physics: the construction of large γ-ray arrays to investigate prompt γ-rays from fission and deep-inelastic reactions; and the availability of radioactive nuclei from fragmentation and spallation reactions. In this review examples will be given of the advances that have been made in our understanding of the properties of neutron-rich nuclei. The examples are necessarily selective, given the limitations of space and time.

Recent developments in atomic physics for the simulation of hot plasmas

Simulations of plasmas in which atoms are not completely stripped require atomic data, like average charge, ionization energies, and radiative properties (emissivity, opacity). These depend on populations of energy levels. The basic framework for obtaining the latter is the collisional radiative model (CRM), which bridges the gap between the low-density Corona Equilibrium (CE) and Local Thermodynamic Equilibrium (LTE). However, for nearly all but the simplest ions, the number of relevant bound states and cross sections is prohibitive. In this review we summarize some recent methods for handling complex ions: By focusing on an exact evaluation of relevant information and ignoring unobservable features, unresolved transition arrays (UTA) are obtained. The supertransition arrays (STA) model combines many UTAs in LTE. The STA code was recently extended to a non-LTE CRM called SCROLL. Using these models could improve radiation simulation in hot plasmas, even for simple spectra.