Maurice Goldhaber

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In recent years there has been considerable growth in research in so-called 'interface' areas where nuclear physics, particle physics and astrophysics meet; sharing common goals and language, as well as instrumentation techniques. Examples include: Probing the standard model by measuring elements of the CKM matrix The use of colliders and detectors with access to the highest energies to search for the underlying structure of matter and energy Fundamental interactions at the nuclear and particle level required to understand processes from solar burning to supernovae Neutrino physics; including oscillations, mass and interactions probing the standard solar model Hadronic physics dealing with the interactions, binding and structure of the strongly interacting particles under various conditions The increased use of 4 detectors in low-energy nuclear physics to select specific processes of interest. These are only a few examples of what has become a major meeting place for much of the exciting physics of the early 21st Century. In today's science, the spectrum of particles, the nucleus as well as the large-scale components of the universe, are our laboratories for testing and understanding nature.These exciting areas of cross-over require much further research and exploration. The Editorial Board and staff of Journal of Physics G: Nuclear and Particle Physics wish to strengthen their support for physicists working in such areas of intersection. To make our coverage of these interconnections more explicit, we have redrafted our scope statement as follows:Theoretical and experimental topics in the physics of elementary particles and fields, intermediate-energy physics and nuclear physics. The particle astrophysics section includes all aspects of experimental and theoretical research into cosmic rays, nuclear and particle astrophysics, gamma ray astronomy, neutrino astrophysics and dark matter. We also welcome articles from all areas of interface between these fields.We would like to invite all physicists working on these topics to publish their work in the pages of J.Phys.G. Naturally we shall continue to welcome outstanding research in our core nuclear and particle physics areas.Since its launch in 1975, J.Phys.G has had a broad scope covering all aspects of the physics of elementary particles, nuclear physics, and nuclear and particle astrophysics. We have always felt this provides the journal's authors and readers with a unique overview of these increasingly interconnected subjects.When you publish in J.Phys.G you'll benefit from fast and impartial peer review, with an average receipt-to-first decision time for papers of 58 days. We strive to provide outstanding author service with online article submission, tracking of manuscripts and electronic refereeing. Publishing with us provides your paper with wide international visibility in print and online at www.iop.org/journals/jphysg. As well as being accessible to our subscribers, each new paper is freely available to all for 30 days on our Website

These notes are an outgrowth of an advanced undergraduate course taught at the University of Maryland, College Park. They are intended as an introduction to various aspects of particle and nuclear physics with an emphasis on the role of symmetry. The basic philosophy is to introduce many of the fundamental ideas in nuclear and particle physics using relatively sophisticated mathematical tools -- but to do so in as a simplified a context to explain the underlying ideas. Thus, for example, the Higgs mechanism is discussed in terms of an Abelian Higgs model. The emphasis is largely, but not entirely theoretical in orientation. The goal is for readers to develop an understanding of many of the underlying issues in a relatively sophisticated way.

Being a highly subjective account of the last two decades of nuclear spectroswpy intended for a mixed audience of nuclear and non-nuclear physicists. A11 of you who are not nuclear physicists are well aware of the more sensational developments in nuclear physics in the last 15 years; the role of beta-decay in the discovery of the non-conservation of parity, especially the work of Madame Wu and her collaborators, the beautiful GoldhaberGrodzins-Sunyar experiment on the helicity of the neutrino, the Mossbauer effect. But, do you know as much about our major effort in time and interest - namely, the study of the structure of nuclei? Today I would like to talk to you about the structure of the light nuclei, a subject which has seen a great deal of activity in the last few years and one which has been my work and play for 18 years. This will be both a very personal view and a very personal history. As always, the hope is that reflection on the past can help guide the future. The major part of the nuclear spectroscopy in which I have been involved has used the 3.7-Mev Van de Graaff accelerator at Brookhaven National Laboratory. Because of the Coulomb barrier between target nuclei and projectile, our studies with the Van de Graaff have been limited to nuclei with rather low Z - those with mass numbers less than about 50. These we term the light nuclei. Let me give you a brief history of research on the structure of the light nuclei. The initial work focussed largely on the nuclei lighter than oxygen. Following the development of the shell model by Mayer l and Jensen 2 in the late forties and early fifties, and the historic Rev. Mod. Phys. article of Inglis 3 in 1953, it was clear that the shell model had a high degree of applicability in the nuclei lighter than 016. From Li 5 through the lp oscillator shell is filling and, as it fills, the relative importance of thel. s term increases so that the situation changes from predominantly LS-coupling to predominantly jj-coupling. This intermediate coupling situation was treated fairly successfully in the fifties and early sixties by Kurath,

By coupling of mechanics, optics, and mathematics, Theodor Svedberg invented the ultracentrifuge, which allowed separation of important biological materials by high centrifugal force, resulting in physical chemical separation and characterization of atherogenic low density lipoproteins and other biological molecules. Combining physics, chemistry and engineering, Ernest Lawrence invented the cyclotron, resulting in advancing nuclear physics, particle physics, molecular and materials science, and nuclear medicine. Using isotope– C-14, Melvin Calvin elucidated the photosynthesis cycle. Coupling photomultiplier tubes (PMTs) with NaI scintillation crystal, Hal Anger revolutionized nuclear imaging. Shashi Kumar and co-workers used biology and polymerase chain technology for the detection of mislabeled food materials. Combinations of biotechnology, chromatography, analytical chemistry and electron microscopy have resulted in organic chemists’ improved ability to synthesize isoprene compounds of interest. These are some of the examples that have moved science forward and demonstrate that physical, chemical, biological, and biotechnological sciences are incomplete without each other. The single most important advance in the use of centrifugal force to separate biologically important substances was the coupling of mechanics, optics and mathematics, by T. Svedberg and J.W. Williams in the 1920′s (http://humantouchofchemistry.com/theodorsvedberg.htm). The sedimentation coefficient is the rate at which particles of a given size and shape travel to the bottom of a tube under centrifugal force. The Svedberg unit is named after the Swedish chemist Theodor Svedberg (1884–1971), winner of the 1926 Nobel Prize in Chemistry for his work on colloids and his invention of the ultracentrifuge. Combining physics, chemistry and engineering Ernest Lawrence of the Lawrence Berkeley Laboratory invented Cyclotron (Fig 1). (http://www.nobelprize.org/nobel_prizes/physics/laureates/1939/lawrence-bio.html). The First Cyclotron, measuring only 5 inches in diameter, was constructed of glass, sealing wax and bronze; the material cost was about $25 (Fig 1). For his invention of the cyclotron, Lawrence was awarded the 1939 Nobel Prize in Physics.

Brookhaven National Laboratory is a national research center in which the Laboratory staff and scientists from other institutions, especially those located in the northeastern United States, carry out fundamental and applied research in the nuclear sciences and related subjects as an integral part of the nation-wide program of the Atomic Energy Commission. It was established as a cooperative venture between nine leading northeastern universities (Columbia, Cornell, Harvard, Johns Hopkins, the Massachusetts Institute of Technology, the University of Pennsylvania, Princeton, the University of Rochester, and Yale) and the government in recognition of the need for large and expensive equipments, and concentrations of scientific manpower for the successful prosecution of nuclear research. The primary objectives of the Laboratory are: 1. To seek new knowledge in the nuclear sciences and related fields with emphasis on programs that require such large-scale research tools as nuclear reactors, accelerators, and special laboratories which are beyond the scope of most or all individual institutions. 2. To encourage appropriate use of its facilities by scientists of college, university, industrial, and other laboratories. 3. To assist the Atomic Energy Commission in the solution of specific problems by utilizing the Laboratory's unique facilities or the special talents of its staff. 4. To make use of the Laboratory as an important auxiliary in the training of scientists and engineers and otherwise to assist in the dissemination of scientific and technical knowledge. The cooperative nature of the Brookhaven program is of paramount importance. A significant and increasing fraction of the scientists and engineers directly engaged in the scientific program is comprised of visitors from other institutions who take advantage of the special opportunities at Brookhaven to carry out specific research and to gain useful knowledge and experience.

Brookhaven National Laboratory is a national research center in which the Laboratory staff and scientists from other institutions, especially those located in the northeastern United States, carry out fundamental and applied research in the nuclear sciences and related subjects as an integral part of the nation-wide program of the Atomic Energy Commission. It was established as a cooperative venture between nine leading northeastern universities (Columbia, Cornell, Harvard, Johns Hopkins, the Massachusetts Institute of Technology, the University of Pennsylvania, Princeton, the University of Rochester, and Yale) and the government in recognition of the need for large and expensive equipments, and concentrations of scientific manpower for the successful prosecution of nuclear research. The primary objectives of the Laboratory are: 1. To seek new knowledge in the nuclear sciences and related fields with emphasis on programs that require such large-scale research tools as nuclear reactors, accelerators, and special laboratories which are beyond the scope of most or all individual institutions. 2. To encourage appropriate use of its facilities by scientists of college, university, industrial, and other laboratories. 3. To assist the Atomic Energy Commission in the solution of specific problems by utilizing the Laboratory's unique facilities or the special talents of its staff. 4. To make use of the Laboratory as an important auxiliary in the training of scientists and engineers and otherwise to assist in the dissemination of scientific and technical knowledge. The cooperative nature of the Brookhaven program is of paramount importance. A significant and increasing fraction of the scientists and engineers directly engaged in the scientific program is comprised of visitors from other institutions who take advantage of the special opportunities at Brookhaven to carry out specific research and to gain useful knowledge and experience.

Scientific foundation models hold great promise for advancing nuclear and particle physics by improving analysis precision and accelerating discovery. Yet, progress in this field is often limited by the lack of openly available large-scale datasets, as well as standardized evaluation tasks and metrics. Furthermore, the specialized knowledge and software typically required to process particle physics data pose significant barriers to interdisciplinary collaboration with the broader machine learning community. This work introduces a large, openly accessible dataset of 10 million simulated protonproton collisions, designed to support self-supervised training of foundation models. To facilitate ease of use, the dataset is provided in a common NumPy format. In addition, it includes 70,000 labeled examples spanning three well-defined downstream tasks – track finding, particle identification, and noise tagging – to enable systematic evaluation of the foundation model’s adaptability. The simulated data are generated using the Pythia Monte Carlo event generator at a center-of-mass energy of and processed with Geant4 to include realistic detector conditions and signal emulation in the sPHENIX Time Projection Chamber at the Relativistic Heavy Ion Collider, located at Brookhaven National Laboratory. This dataset resource establishes a common ground for interdisciplinary research, enabling machine learning scientists and physicists alike to explore scaling behaviors, assess transferability, and accelerate progress toward foundation models in nuclear and high-energy physics. The complete simulation and reconstruction chain is reproducible with the sPHENIX software stack. All data and code locations are provided under Data Accessibility.

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Journal of Physics G: Nuclear and Particle Physics is committed to bringing its readers timely reviews in topics of interest to the nuclear and particle physics community, and an active programme of Topical Reviews is scheduled for future issues. Appropriate topics and authors are identified by the Editorial Board prior to invitation and commissioning of reviews, but any suggestions of suitable topics or offers of review contributions will be welcomed by the Board.

This year9s Nobel Prize in physics honors Yoichiro Nambu, Makoto Kobayashi, and Toshihide Maskawa for discoveries in particle physics.

Richard Guy Helmer

The physics of objects smaller than an atom was once a single specialty. It was called nuclear physics because its main concern was the nature and structure of atomic nuclei. But in the last decade or so a separation has taken place between the physicists who studied subatomic matter at very high energies, the so-called particle physicists, and nuclear physicists proper. The particle physicists took as their domain the nature and behavior of individual particles, rather than collective entities like a nucleus. They have gone on to higher and higher energies and ever more startling discoveries in their search for the most fundamental constituents of matter. Lately the particle physicists have experienced a certain frustration. They have been having a hard time trying to mate theory and experiment, and many of the objects they have discovered are so ephemeral that some of them are beginning to wonder whether they have anything to do with the structure of stable matter. The structure of nuclei is fundamental to the structure of stable matter, and if it ever becomes well understood, the age-old dream of making the elements one desires instead of depending on what nature gives might be a step nearer. And among the nuclear structure physicists, there is a feeling of hope and an expectation that old frustrations are about to be relieved. The nuclear physicists are building a new generation of particle accelerators, which, they expect, will give them an entirely new dimension of information about nuclear structure. Heretofore their experiments have concerned the nucleus as a whole. Now they want to study the nucleus in more detail. They want to see how small regions of it look and how individual nuclear particles behave and interact with each other within the nucleus. So far they have not had the energy available to get such data. Technology is now allowing them to build the machines that will do it. And those are now being built at several sites in the U.S., as well as in the Soviet Union, Switzerland and Canada. The machines are commonly called meson factories because one of their primary functions is the production of copious beams of pi and mu mesons with which to probe nuclei. In some cases they also yield protons and negative hydrogen ions, hydrogen atoms with an extra electron each. Each of these particles interacts in a different way with the particles in the nucleus, and each gives a different perspective on nuclear structure. Putting the perspectives together, physicists hope, will give a comprehensive picture. The meson factories bring nuclear structure physics into an energy range, hundreds of millions of electron volts, where the physics has not usually been done. The energy is necessary to get the detailed information, but achieving the energy was not the major technological stumbling block in the construction of meson factories; intensity was the problem. The particle beams have to be very intense-contain a large number of particles-to make enough of the desired reactions happen to get meaningful data. Gradual improvements in beam handling techniques have made the management of very intense beams possible, but they still give designers problems with radioactivity. There are unique problems in the handling of intensely radioactive material in targets, says Dr. R. L. Burman of Los Alamos Scientific Laboratory, speaking of the now-building Los Alamos Meson Physics Facility. The solution, he says, is to design a so-called

In order to understand how matter 15 billion years ago in the form of quarks, gluons and leptons at a temperature of 2 × 1012 °K evolved to become today’s Universe, the goal of relativistic and ultra-relativistic heavy ion physics is to understand the equation of state of nuclear, hadronic and partonic matter. This quest is of cross-disciplinary interest. The phase transition from partonic matter to hadronic matter tens of micro-seconds after the beginning of the universe is of interest to cosmology. Fluctuations during this phase transition would influence nucleosynthesis and the understanding of baryonic inhomogeneities in the universe. The nuclear matter equation of state, which describes the incompressibility of nuclear matter, governs neutron star stability. It determines the possible existence of strange quark matter stars and the dynamics of supernova expansion in astrophysics. The existence of collective nuclear phenomena in nuclear physics is also determined by the nuclear equation of state. In relativistic heavy ion collisions collective nuclear flow has been observed and is being studied extensively to obtain a better understanding of the incompressibility of nuclear matter. In high energy nuclear and particle physics, production and excitations of hadronic final states have been studied in detail and are important to an overall understanding of the equation of state of nuclear matter at finite temperature. The possibility in ultra-relativistic heavy ion collisions to create and study highly excited hadronic and partonic degrees of freedom provides a unique opportunity for understanding the behavior of nuclear, hadronic and partonic matter. Study of the QCD vacuum, of particular interest in particle physics, would provide a better understanding of symmetry-breaking mechanisms and the origins of the masses of the various quarks and particles. Creation and study of the quark-gluon plasma, an excitation of the QCD vacuum, is the goal of physicists in the new field of ultra-relativistic heavy ion collisions.

PHYSICS LABSPARIS-- An unpublished report, prepared at the request of science minister Claude AllA¨gre, is said to recommend some form of merger between the two main bodies responsible for subatomic physics in France: the National Institute of Nuclear and Particle Physics (IN2P3), which is part of the giant CNRS basic research agency; and the Atomic Energy Commission's Department of Astrophysics, Nuclear Physics, Particle Physics, and Associated Instrumentation (DAPNIA). Although this marriage would be consistent with AllA¨gre's long-stated desire to end duplication of research efforts and enhance scientific collaboration, some physicists argue that it would weaken the role of the CNRS and give the Atomic Energy Commission too much influence over research priorities.