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Multi-Nucleon Transfer (MNT) reactions have been used for decades as a reaction mechanism, in order to populate excited states in nuclei far from stability and to perform nuclear structure studies. Nevertheless, the development of set-ups involving high acceptance tracking magnetic spectrometers (mainly existing in Europe), coupled with the Advanced GAmma Tracking Array (AGATA) opens new possibilities, especially if they are used in conjunction with high-intensity stable beams or ISOL RIBs. In this article, we will discuss the capabilities of such set-ups aiming at different goals, including complete information in high-resolution spectroscopy as well as lifetime measurements.

For the first time in an application to nuclear astrophysics, a process induced by the unstable 5He = (4He-n) nucleus, the 3He+5He→2α reaction, has been studied through the Trojan Horse Method (THM). For that purpose, the quasi-free (QF) contribution of the 9Be(3He,αα)4He reaction was selected at E3 He =4 MeV incident energy. The reaction was studied in a kinematically complete experiment following a recent publication, where for the quasi free contribution the momentum distribution between α and 5He particle cluster in the 9Be nucleus in the ground state have been extracted. The angular distribution of the QF 3He+5He→2α reaction was measured at θcm = 78°–115°. The energy dependence of the differential cross section of the 3He+5He→2α virtual reaction was extracted in the energy range Ecm = 0–650 keV. In conclusion, the total cross section obtained from the Trojan-horse method was normalized to absolute cross sections from a theoretical calculation in the energy range Ecm =300–620 keV.

Based on the rotational symmetry of isolated quantum systems, Racah’s algebra plays a significant role in nuclear, atomic and molecular physics, and at several places elsewhere. For N-particle (quantum) systems, for example, this algebra helps carry out the integration over the angular coordinates analytically and, thus, to reduce them to systems with only N (radial) coordinates. However, the use of Racah’s algebra quickly leads to complex expressions, which are written in terms of generalized Clebsch–Gordan coefficients, Wigner n-j symbols, (tensor) spherical harmonics and/or rotation matrices. While the evaluation of these expressions is straightforward in principle, it often becomes laborious and prone to making errors in practice. We here expand Jac, the Jena Atomic Calculator, to facilitate the sum-rule evaluation of typical expressions from Racah’s algebra. A set of new and revised functions supports the simplification and subsequent use of such expressions in daily research work or as part of lengthy derivations. A few examples below show the recoupling of angular momenta and demonstrate how Jac can be readily applied to find compact expressions for further numerical studies. The present extension makes Jac a more flexible and powerful toolbox in order to deal with atomic and quantum many-particle systems.

TALYS is a software package for the simulation of nuclear reactions below 200 MeV. It is used worldwide for the analysis and prediction of nuclear reactions and is based on state-of-art nuclear structure and nuclear reaction models. A general overview of the implemented physics and capabilities of TALYS is given. The general nuclear reaction mechanisms described are the optical model, direct reactions, compound nucleus model, pre-equilibrium reactions and fission. The most important nuclear structure models are those for masses, discrete levels, level densities, photon strength functions and fission barriers. A wide variety of nuclear reactions simulated with TALYS will be demonstrated, ranging from low-energy neutron cross sections, astrophysics, high-energy charged particle reactions and other reactions. TALYS is a nuclear reaction software which aims to give a complete description of nuclear reaction observables, and to be an important link between fundamental nuclear physics and applications.

The spliceosome catalyses the excision of introns from pre-mRNA in two steps, branching and exon ligation, and is assembled from five small nuclear ribonucleoprotein particles (snRNPs; U1, U2, U4, U5, U6) and numerous non-snRNP factors 1 . For branching, the intron 5′ splice site and the branch point sequence are selected and brought by the U1 and U2 snRNPs into the prespliceosome 1 , which is a focal point for regulation by alternative splicing factors 2 . The U4/U6.U5 tri-snRNP subsequently joins the prespliceosome to form the complete pre-catalytic spliceosome. Recent studies have revealed the structural basis of the branching and exon-ligation reactions 3 , however, the structural basis of the early events in spliceosome assembly remains poorly understood 4 . Here we report the cryo-electron microscopy structure of the yeast Saccharomyces cerevisiae prespliceosome at near-atomic resolution. The structure reveals an induced stabilization of the 5′ splice site in the U1 snRNP, and provides structural insights into the functions of the human alternative splicing factors LUC7-like (yeast Luc7) and TIA-1 (yeast Nam8), both of which have been linked to human disease 5 , 6 . In the prespliceosome, the U1 snRNP associates with the U2 snRNP through a stable contact with the U2 3′ domain and a transient yeast-specific contact with the U2 SF3b-containing 5′ region, leaving its tri-snRNP-binding interface fully exposed. The results suggest mechanisms for 5′ splice site transfer to the U6 ACAGAGA region within the assembled spliceosome and for its subsequent conversion to the activation-competent B-complex spliceosome 7 , 8 . Taken together, the data provide a working model to investigate the early steps of spliceosome assembly. The cryo-electron microscopy structure of the Saccharomyces cerevisiae prespliceosome provides insights into splice-site selection and early spliceosome assembly events.

This article provides a comprehensive review of the evolution of the nuclear shape concept, a cornerstone in nuclear physics. Tracing its historical development from the early 20th century, we highlight key milestones and paradigm shifts that have shaped our understanding. The review explores the transition from the initial spherical model to the introduction of nuclear deformation, emphasizing the contributions of the liquid drop model and the unified model. The pivotal role of nuclear shapes in elucidating various nuclear phenomena and their profound impact on both theoretical and experimental nuclear physics are discussed in depth. The article underscores the relevance of nuclear shape in contemporary physics, particularly in light of groundbreaking findings from ultra-relativistic heavy ion collisions. These recent results illustrate the enduring significance of nuclear shape in advancing our comprehension of nuclear structure and reactions.

. Photon strength functions describing the average response of the nucleus to an electromagnetic probe are key input information in the theoretical modelling of nuclear reactions. Consequently they are important for a wide range of fields such as nuclear structure, nuclear astrophysics, medical isotope production, fission and fusion reactor technologies. They are also sources of information for widely used reaction libraries such as the IAEA Reference Input Parameter Library and evaluated data files such as EGAF. In the past two decades, the amount of reaction gamma-ray data measured to determine photon strength functions has grown rapidly. Different experimental techniques have led to discrepant results and users are faced with the dilemma of which (if any) of the divergent data to adopt. We report on a coordinated effort to compile and assess the existing experimental data on photon strength functions from the giant dipole resonance region to energies below the neutron separation energy. The assessment of the discrepant data at energies around or below the neutron separation energy has been possible only in a few cases where adequate information on the model-dependent analysis and estimation of uncertainties was available. In the giant dipole resonance region, we adopt the recommendations of the new IAEA photonuclear data library. We also present global empirical and semi-microscopic models that describe the photon strength functions in the entire energy region and reproduce reasonably well most of the experimental data. The compiled experimental photon strengths and recommended model calculations are available from the PSF database hosted at the IAEA ( http://www-nds.iaea.org/PSFdatabase ).

Spin-parity assignments of nuclear levels are critical for understanding nuclear structure and reactions. However, inconsistent notation conventions and ambiguous reporting in research papers often lead to confusion and misinterpretations. This paper examines the policies of the Evaluated Nuclear Structure Data File (ENSDF) and the evaluations by Endt and collaborators, highlighting key differences in their approaches to spin-parity notation. Sources of confusion are identified, including ambiguous use of strong and weak arguments and the conflation of new experimental results with prior constraints. Recommendations are provided to improve clarity and consistency in reporting spin-parity assignments, emphasizing the need for explicit notation conventions, clear differentiation of argument strengths, community education, and separate reporting of new findings. These steps aim to enhance the accuracy and utility of nuclear data for both researchers and evaluators.

Machine learning (ML) is becoming a new paradigm for scientific research in various research fields due to its exciting and powerful capability of modeling tools used for big-data processing tasks. In this review, we first briefly introduce the different methodologies used in ML algorithms and techniques. As a snapshot of many applications by ML, some selected applications are presented, especially for low- and intermediate-energy nuclear physics, which include topics on theoretical applications in nuclear structure, nuclear reactions, properties of nuclear matter, and experimental applications in event identification/reconstruction, complex system control, and firmware performance. Finally, we present a summary and outlook on the possible directions of ML use in low-intermediate energy nuclear physics and possible improvements in ML algorithms.

The neutron-induced nuclear reaction data play an important role in the studies of the nuclear structure, the nuclear reaction mechanism and the nuclear energy applications. Particularly, the cross section data of the neutron-induced nuclear reactions are an indispensable component in the studies of the nuclear technology such as fusion devices, fission power plants, and accelerators. In the actual cross section measurements of the neutron-induced nuclear reactions with natural samples containing many stable isotopes, many nuclear reactions will take place at the same time and the mutual interference of various nuclear reactions is difficult to avoid. In this case, the standardization expressions of the neutron-induced nuclear reactions are particularly important. The expressions of the neutron-induced nuclear reactions in the relevant literatures are various and confusing, which is bad not only for the academic exchanges and the construction of nuclear reaction databases, but also for the basic research and the related application research of the nuclear physics. Some problems related to the expressions on the neutron-induced nuclear reactions were carefully combed and discussed, and the suggestions on the standardization expressions of the neutron-induced nuclear reactions (which were divided into the single nuclear reaction and the multiple nuclear reaction producing the same daughter nucleus. And the former was further divided into the daughter nucleus with metastable state and the daughter nucleus without metastable state, while the latter into the nuclear reaction that directly produces the same daughter nucleus and the nuclear reaction that directly and indirectly produces the same daughter nucleus) were given. The work is useful for the academic exchanges, the construction of the nuclear reaction databases, the basic researches and the related application researches of the nuclear physics.