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The rapid neutron capture or ‘r process’ of nucleosynthesis is believed to be responsible for the production of approximately half the natural abundance of heavy elements found on the periodic table above iron (with proton number Z = 26 ) and all of the heavy elements above bismuth ( Z = 83 ). In the course of creating the actinides and potentially superheavies, the r process must necessarily synthesize superheavy nuclei (those with extreme proton numbers, neutron numbers or both) far from isotopes accessible in the laboratory. Many questions about this process remain unanswered, such as ‘where in nature may this process occur?’ and ‘what are the heaviest species created by this process?’ In this review, we survey at a high level the nuclear properties relevant for the heaviest elements thought to be created in the r process. We provide a synopsis of the production and destruction mechanisms of these heavy species, in particular the actinides and superheavies, and discuss these heavy elements in relation to the astrophysical r process. We review the observational evidence of actinides found in the Solar system and in metal-poor stars and comment on the prospective of observing heavy-element production in explosive astrophysical events. Finally, we discuss the possibility that future observations and laboratory experiments will provide new information in understanding the production of the heaviest elements. [ABSTRACT FROM AUTHOR]

The assessment of an α -particle optical model potential for nucleon–induced α -emission within the A ∼ 60 mass-number range [Avrigeanu and Avrigeanu (Eur. Phys. J. A 57:54, 2021)] is completed by analysis of neutron–induced reactions on stable Ni isotopes. The same consistent set of nuclear–model input parameters as well as first uncertainty analysis of calculated cross sections related to the accuracy of independent data formerly used within parameter setting up have been concerned. Description of absorption and emission of α -particles by the same potential is validated, while the pickup direct reaction and Giant Quadrupole Resonance (GQR) α -emission beyond the statistical predictions are confirmed by recent data around the GQR energies. [ABSTRACT FROM AUTHOR]

Probing the structure of an atomic nucleus by the electromagnetic interaction can be the cleanest and most direct way to obtain information on how the constituting nucleons are organizing themselves within the nucleus. Precise characterization of photonuclear reactions has contributed significantly to the establishment of modern nuclear physics. A brief overview on the Nuclear Resonance Fluorescence method, its applications and potential future opportunities will be given. In particular, we address recent studies of the dipole strength distributions of 76Se and 40Ar, of the determination of the Photon Strength Function of 128Te, and dare an outlook to even more sensitive measurements in the future. [ABSTRACT FROM AUTHOR]

The Soreq Applied Research Accelerator Facility (SARAF) is under construction in the Soreq Nuclear Research Center at Yavne, Israel. When completed at the beginning of the next decade, SARAF will be a user facility for basic and applied nuclear physics, based on a 40 MeV, 5 mA CW proton/deuteron superconducting linear accelerator. Phase I of SARAF (SARAF-I, 4 MeV, 2 mA CW protons, 5 MeV 1 mA CW deuterons) is already in operation, generating scientific results in several fields of interest. The main ongoing program at SARAF-I is the production of 30 keV neutrons and measurement of Maxwellian Averaged Cross Sections (MACS), important for the astrophysical s-process. The world leading Maxwellian epithermal neutron yield at SARAF-I (5×1010 epithermal neutrons/s), generated by a novel Liquid-Lithium Target (LiLiT), enables improved precision of known MACSs, and new measurements of low-abundance and radioactive isotopes. Research plans for SARAF-II span several disciplines: precision studies of beyond-Standard-Model effects by trapping light exotic radioisotopes, such as 6He, 8Li and 18, 19, 23Ne, in unprecedented amounts (including meaningful studies already at SARAF-I); extended nuclear astrophysics research with higher energy neutrons, including generation and studies of exotic neutron-rich isotopes relevant to the rapid (r-) process; nuclear structure of exotic isotopes; high energy neutron cross sections for basic nuclear physics and material science research, including neutron induced radiation damage; neutron based imaging and therapy; and novel radiopharmaceuticals development and production. In this paper we present a technical overview of SARAF-I and II, including a description of the accelerator and its irradiation targets; a survey of existing research programs at SARAF-I; and the research potential at the completed facility (SARAF-II). [ABSTRACT FROM AUTHOR]