International Journal of Modern Physics E

This is a summary of the recent workshop "Strong QCD from Hadron Structure Experiments", based on contributions from the conveners of the topical sessions. It aims to provide the scientific background for future joint projects between the experts from these diverse areas in hadron physics. (Read full article.)

This paper reviews the properties of neutron stars based on the recent multi-messenger observations including electromagnetic waves from the low-mass X-ray binaries and gravitational waves from the merger of neutron star binaries. Based on these observations, we investigate theoretical models for dense nuclear matter and discuss their implications to the neutron star observations such as mass, radius, cooling, and tidal deformability. (Read full article.)

The accurate knowledge of the nuclear level density is crucial for understanding the nuclear structure and for numerous applications including astrophysical reactions. In this review paper, we discuss the shell-model description of the nuclear level density, the use of the statistical moments method and underlying physics. (Read full article.)

As one promising approach for producing nuclei beyond the β-stability line, the multinucleon transfer (MNT) process has been extensively investigated in past decades. An overview of the theoretical progress on production of isotopes in MNT process is presented. (Read full article.)

This work sheds light upon how the atomic nucleus polarizes throughout the nuclear chart. Deviations from the well-known behavior of the nuclear dipole polarizability — which smoothly increases with increasing atomic mass number — are investigated. Relative enhancements are found for light nuclei as the nuclear symmetry energy decreases and, within a nucleus, as its excitation energy increases. These two properties are related by a diminishing binding energy of the nuclear system. Contrarily, hindrances of nuclear polarizability are observed in the photo-neutron cross-section data and photon-strength functions of semi-magic nuclei with N=28, 50 and 82, which support the presence of shell effects at low-lying excitations and — assuming validity of the Brink-Axel hypothesis — at high-excitation energies up to the quasi-continuum region. These features assign the nuclear dipole polarizability as a sensitive measure of the long-range correlations of the nuclear force, and provide a new spectroscopic probe to investigate collective phenomena, shell closures, and the elusive nuclear symmetry energy. Particular cases of quadrupole collectivity are also discussed in terms of the available, and yet so scarce, information on nuclear polarizability (e.g. Sn and Ni isotopes). View Full Article

The structure of exotic nuclei sheds new light on the linkage of the nuclear structure to the nucleonic interaction. The self-consistent mean-field (SCMF) theories are useful to investigate this linkage, which are applicable to many nuclei covering almost the whole range of the nuclear chart without artificial truncation of model space. For this purpose, it is desired to develop effective interaction for the SCMF calculations well connected to the bare nucleonic interaction. Focusing on ground-state properties, I show the results of SCMF calculations primarily with the Michigan-three-range-Yukawa (M3Y)-type semi-realistic interaction, M3Y-P6 and M3Y-P6a to be precise, and discuss in detail how the nucleonic interaction affects the structure of nuclei including those far off the β-stability. View Full Article

The Skyrme model is a low energy effective field theory of strong interactions where nuclei and baryons appear as collective excitations of pionic degrees of freedom. In the last years, there has been a revival of Skyrme's ideas and new related models, and some of them with BPS bounds (topological lower energy bounds) have been proposed. It is the aim of this paper to review how they can be applied to the study of neutron stars allowing for a description by means of topological solitons. We will focus on different aspects as the equation of state or the mass-radius relation, where we find that high maximal masses are supported. View Full Article

Nuclear masses are the most fundamental of all nuclear properties, yet they can provide a wealth of knowledge, including information on astrophysical sites, constraints on existing theory, and fundamental symmetries. In nearly all applications, it is necessary to measure nuclear masses with very high precision. As mass measurements push to more short-lived and more massive nuclei, the practical constraints on mass measurement techniques become more exacting. Various techniques used to measure nuclear masses, including their advantages and disadvantages are described.

The Facility for Rare Isotope Beams (FRIB) Project has entered the phase of beam commissioning starting from the room-temperature front end and the superconducting linac segment of first 15 cryomodules. With the newly commissioned helium refrigeration system supplying 4.5K liquid helium to the quarter-wave resonators and solenoids, the FRIB accelerator team achieved the sectional key performance parameters as designed ahead of schedule accelerating heavy ion beams above 20MeV/u energy. Thus, FRIB accelerator becomes world's highest-energy heavy ion linear accelerator.

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