For scientists who study matter at extreme energy, understanding the massive cracking of large atomic cores like lead in close proximity to each other (in fact without collision) is an important way to understand the power that controls the power of the universe. These rare interactions, which affect lead atoms only through their powerful electric fields, provide a unique opportunity to observe how energy from light particles destroys the atomic structure. The researchers decided to take a closer look at how protons released during the process, and how these protons were released during the process, with the aim of improving models that describe this interaction and helping to develop future research facilities such as electron colliders (such as research nuclei) (a next-generation machine used to study nuclei).
Under the umbrella of Alice’s collaboration, the research team of the Large Ion Collider Experiment of the EuroNuclear Research Organization’s main particle physics program used the experiment’s advanced detection system to collect data in the world’s largest particle accelerator, known as the Large Handron Collider. They conducted the first detailed study of the event where protons were emitted together with neutrons, which were also located in neutral particles in the nucleus, when lead atoms approached each other at high speeds. Their findings published in Physical Review C describe different combinations of how particles are released and compare these observations with a widely used simulation tool called the Relativity Electromagnetic Dissociation Model, which estimates how atomic nuclei split under the influence of electricity.
In most cases, these breakthrough events did not result in proton emissions, confirming that such results are relatively few. However, these patterns can be clearly observed when protons are emitted. The team found that the model closely matched the observed events and emitted no protons or multiple protons together. However, it seems to underestimate the frequency of events involving one or two protons. The researchers also analyzed the emission of a single proton with one, two or three neutrons and found that the model often overestimates the frequency of such events.
Perhaps most notably, the way these particles appear to be emitted in line with the creation of new forms of chemical elements. When only neutrons are released, different versions of lead (called isotopes) are formed. When one or more protons are emitted, the resulting elements include thallium, mercury, and gold. These findings help scientists better understand how the components of atoms are rearranged during these interactions and what new matter may emerge. As Dr. Acharya explains, “The relativity electromagnetic separation model shows that these proton and neutron emissions are related to the generation of elements such as thallium and Gold, which we now observe with a clearer attitude.”
With a highly sensitive detector, the detector is located to capture particles moving at steep angles, and the team measured protons and neutrons with high accuracy. Detectors designed specifically for measuring protons are directly aligned with the path of the lead atomic beam, while other detectors are used to detect neutrons. Scientists have adopted a careful statistical method—using patterns and probabilities in the collected data—to explain the energy readings of these devices. This approach allows them to identify events related to the study. They also made necessary adjustments to their analysis to illustrate particles that may not have been found or misunderstood. Since protons tend to lose more energy and travel, this part is especially important compared to neutrons.
These findings enhance our understanding of how large atomic structures affected by nearby atomic electric fields break. At the same time, the study challenges part of the relativity electromagnetic dissociation model, showing that improvements are still needed, although it remains a valuable tool. As Dr. Acharya points out, “these results are the benchmarks of theoretical models and support the design of future facilities where understanding this dissociation process is crucial.”
From a larger perspective, this study links experimental data to predictions of computer simulations, a digital model used to replicate physical phenomena. The work of the Big Ion Collider Experimental Group marks a meaningful advance in nuclear science. It provides a clearer understanding of how lead atoms behave under extreme conditions and sheds light on how atomic components can be reassembled into new materials in outer space and laboratory environments.
Journal Reference
S. Acharya et al., “Proton emission in ultra-sanitary PB-PB collisions, √snn= 5.02 tev”, Physical Review C, 2025. doi: doi:
About the Author
Alice (Large Ion Collider Experiment) Collaboration is the main international research group of the European Organization for Nuclear Research (CERN). It focuses on studying the behavior of matter under extreme conditions, especially the properties of quark-gel plasma, a state of matter that is believed to exist after the Big Bang. Using powerful particle collisions generated by the Large Hadron Collider, Alice examines how atomic nuclei burst and reform when exposed to incredible high temperatures and energy density. The collaboration includes hundreds of scientists and engineers from institutions around the world working together to explore the fundamental building blocks of the universe. Alice’s advanced detection system is specially designed to analyze heavy ion collisions involving lead nuclei, providing insight into the power of combining protons and neutrons together. The project plays a crucial role in promoting our understanding of nuclear physics and the early universe.
